Evidence of Effectiveness

As discussed in Chapter 1 (see Box 1-2), the assigned protection factor (APF) for a respirator provides a standardized measure of the device’s workplace level effectiveness (OSHA, 2009). Yet, while protection factor studies can provide an estimate of the effectiveness of respirators at reducing exposure (when used in the context of a comprehensive RPP), understanding the effectiveness of RPPs themselves is more challenging.

Few peer-reviewed studies have evaluated the impact of OSHA-mandated RPPs on the safety and health of workers, although anecdotal reports suggest that the presence of a defined RPP provides measurable benefit in protecting employees from inhalation hazards. One example is offered by the Texas Center for Infectious Disease (TCID), a long-term care hospital specializing in the management of difficult-to-treat tuberculosis cases. Prior to 1986, TCID had no formal infection control plan, and annual tuberculin skin tests revealed that 40–50 percent of the center’s staff had positive results, with 1–2 percent of staff developing tuberculosis (NASEM, 2019b). TCID instituted an RPP for its staff in 1995. Employees receive extensive training in how to properly use, disinfect, and store their TCID-supplied elastomeric facepiece respirators, culminating in a written test to ensure correct understanding of the elements of the RPP. Additionally, all staff who enter patient rooms are required to undergo qualitative fit testing (NASEM, 2019b). Since this RPP was implemented, no TCID employees have tested positive on a tuberculin skin test (NASEM, 2019b; The Joint Commission, 2014).

Beyond such anecdotal reports, few studies have directly measured protection against acute or chronic health effects from inhalation hazards following implementation of an RPP. Informative examples can be drawn from the literature on hazards for which biological monitoring is ongoing, such as with the OSHA lead standard. Numerous studies have demonstrated reductions in exposure biomarkers associated with use of respirators in the workplace (Burgess et al., 2001; Grauvogel, 1986; Hyatt, 1984; Liu et al., 2016). However, a notable challenge to assessing the benefits of an RPP is the difficulty of disentangling the consequences of the program from those of use of the respirator itself. An early study by Harris and colleagues (1974) on the effectiveness of respirators for protection from coal dust in underground coal mines showed that even in the absence of an RPP, use of respirators reduced exposures to the dust (Harris et al., 1974).

Further evidence for the potential benefits of RPPs is reported by Cowan and colleagues (2017), who examined fatalities associated with the use of respiratory protection in industrial settings between 1990 and 2012. The authors note a reduction in fatality rates during that time period that appears to be associated with the 1998 publication of OSHA’s revised Respiratory Protection Standard, which included new language designed to ensure that employers would have sufficient guidance to support the selection and maintenance of respiratory protective devices. The findings they report show that historical fatalities associated with respirator use appeared to be associated primarily (>90 percent) with employee error and/or lack of employer compliance with the OSHA Respiratory Protection Standard (e.g., lack of a written RPP, lack of or improper training). The authors conclude that the implementation of the revised OSHA standard, as well as enforcement, outreach, and compliance assistance, had a significantly favorable impact on fatality rates over time (Cowan et al., 2017).

Compliance as a Limiting Factor for the Effectiveness of Respiratory Protection Programs

In addition to evidence of benefit, the committee sought to understand the limitations of RPPs, finding that they relate primarily to employers’ lack of compliance with the OSHA Respiratory Protection Standard. Employers’ failure to comply with program requirements will limit the effectiveness of such systems for protecting workers from occupational respiratory illnesses, although empirical data to demonstrate such impacts are sparse. The reasons for inadequate adoption of and compliance with RPP requirements are not well understood, but research suggests that financial constraints play a major role in the failure to establish health and safety programs more broadly for small businesses (NIOSH, 2018; Vinberg, 2020). A 2007 survey of Kentucky fire departments, for example, found that funding and lack of understanding were the greatest barriers to RPP implementation (Easterling and Prince, 2007).

Several survey-based studies have demonstrated shortcomings of institutional RPPs. In 2001, NIOSH and BLS undertook a broad survey of respirator use and practices among U.S. private-sector employers (DOL and NIOSH, 2003). The survey was mailed to approximately 40,000 private-sector establishments. Based on the survey results, the authors report that respirator use was required in 4.5 percent of these establishments and for 3.1 percent of their employees. Importantly, the survey showed that among establishments requiring respirator use, 91 percent had at least one indicator of a potentially inadequate RPP, while 54 percent had at least five such indicators (Doney et al., 2005). Of the businesses surveyed in which respirators were used, 65.5 percent had no written program detailing how respirators would be used, 49.9 had no written procedure for maintaining their respirators, and 43.3 percent offered no form of fit testing (Doney et al., 2005). These findings suggest that large numbers of employers may not adhere to OSHA requirements for RPPs, putting their workers at risk. However, these data are 20 years old, and the survey was conducted shortly after the 1998 revision of the Respiratory Protection Standard, limiting the conclusions that can be drawn about RPP compliance today. NIOSH and BLS recognize the need to update this survey, and a new survey is planned (BLS, 2021a).

More recently, a study of California hospitals during the 2009–2010 H1N1 influenza pandemic showed that although health care workers reported knowing that they should wear N95 filtering facepiece respirators (FFRs) when in close contact with patients with confirmed or suspected cases of the disease, an evaluation of the hospitals’ written RPPs revealed deficiencies in the areas of recordkeeping, designation of a program administrator, program evaluation, employee training, and fit testing procedures (Beckman et al., 2013). Other studies have found similar shortcomings in workplace RPPs for both health care and public safety workers (Sietsema, 2017; Sietsema et al., 2015).

OSHA citation data support the findings of the survey-based studies described above, further indicating that many employers are not adequately complying with the Respiratory Protection Standard. Mendeloff (2013) carried out an analysis to complement the study undertaken by BLS and NIOSH in 2001. He examined the OSHA database of all inspections in manufacturing establishments in 47 states from 1999 through 2006 (after the OSHA Respiratory Protection Standard had been revised). The study identified inspections and establishments in which respiratory protection violations had been cited, and compared the prevalence of violations by industry with the prevalence reported in the BLS survey of respirator use. The most frequent violation of the OSHA standard (representing one-third of the total) was the failure to have a written RPP. The author found that the probability of citing a respiratory protection violation was comparable across establishment sizes, except for a large decrease at establishments with more than 200 workers. For those workers covered by OSHA, increased enforcement could address RPP limitations related to compliance. However, increased enforcement will not address gaps related to those workers not covered by OSHA’s Respiratory Protection Standard, and the root factors that lead to noncompliance need to be understood.

Other Federal and Nonfederal Programs

The requirements laid out in OSHA’s Respiratory Protection Standard are widely accepted and referenced by other entities with identified inhalation hazards in their workplaces. Federal and state regulations that require respirators in the workplace generally adopt the OSHA standard by reference in whole or in part. Accreditation bodies such as The Joint Commission, a health care accreditation organization, also refer to the OSHA requirements for RPPs as the basis for their respiratory protection guidelines. The Joint Commission cites 1910.134 and the NIOSH–OSHA Hospital Respiratory Protection Program Toolkit: Resources for Respirator Program Administrators.

In some cases, regulations specific to hazards or work practices may go further, specifying the type of respirator to be used and/or specifics of how to administer the respiratory protection program. For example, the Environmental Protection Agency’s (EPA’s) worker protection standard (40 C.F.R. § 170.507) includes requirements for fit testing, medical evaluation, and training that conform to the OSHA Respiratory Protection Standard but requires pesticide handlers to be provided with respirators as specified on the product label. The U.S. Army, which requires compliance with OSHA’s Respiratory Protection Standard per Army Regulation (AR) 11-34 (Department of the Army, 1990), has established Toxic Chemical Agent Safety Standards (Department of the Army, 2018) and provides additional guidance related to respirator selection based on chemical type and concentration. Similarly, some states simply adopt the federal OSHA standard, while others have their own regulations that go beyond what OSHA requires.

Alternative Approaches in the Context of the COVID-19 Pandemic

SARS-CoV-2, which was recognized belatedly as an airborne inhalation hazard, presents extensive challenges for protecting workers and has altered the landscape for regulation of worker respiratory protection. On January 21, 2021, the Biden administration issued an executive order directing OSHA to take action to reduce the risk to workers of contracting COVID-19 at their workplaces (Executive Office of the President, 2021). OSHA issued nonmandatory guidelines for non–health care employers in late January 2021 (OSHA, 2021f) (see Box 3-2), and in June 2021, it issued an emergency temporary standard (ETS) under 29 CFR 1910 Subpart U for workers in health care settings where suspected or confirmed cases of COVID-19 are being treated. The ETS requires employers in health care settings to develop and implement effective plans for mitigating the threat of COVID-19, including developing a COVID-19 plan (in written form if they have more than 10 employees) with a designated safety coordinator, a workplace-specific hazard assessment, and policies and procedures for minimizing the risk of transmission of COVID-19 to employees (29 C.F.R. § 1910.502).

BOX 3-2

OSHA Guidelines for Employers on SARS-CoV-2.

As part of the ETS for workers in health care settings, OSHA developed a “mini RPP” for use in the specific circumstances of the ETS when a respirator is not required but may provide enhanced protection for workers not exposed to confirmed or suspected cases of COVID-19. The mini RPP applies to workers not already covered by a traditional RPP and is not meant as a substitute or replacement for OSHA’s normal Respiratory Protection Standard (29 C.F.R. § 1910.134). Table 3-1 provides a comparison of requirements under OSHA’s standard RPP and the mini RPP when the respirators are employer provided.⁶ The mini RPP has some similarities to OSHA’s voluntary use provision (described below), but if an employer provides respirators to employees under the mini RPP (regardless of device type), that employer must provide training on the use of the device, ensure that seal checks are properly conducted, ensure that the respirators are reused properly, and ensure discontinuation of respirator use under certain conditions (OSHA, 2021d).

TABLE 3-1

Comparison of Requirements for Mini and Full Respiratory Protection Programs (RPPs).

In the absence of a national standard to protect non–health care workers from transmission of SARS-CoV-2, states have developed their own regulations and protocols. Beginning in the early days of the pandemic, state governments issued public health orders covering workplaces, ranging from general guidelines to comprehensive safety and health standards. The first state to promulgate a comprehensive occupational safety and health standard was Virginia, in July 2020 (Virginia DOLI, 2020). This emergency standard required employers to conduct exposure assessments and determine whether a job task poses high, medium, or low risk. It incorporated the hierarchy of controls, and invoked OSHA PPE standards (including the respirator standard) if the assessment concludes that PPE is needed. Use of face coverings was considered to be an administrative control. Oregon and California also issued worker safety standards for COVID-19 exposure (Cal/OSHA, 2020c; Oregon OSHA, 2020).

In other states, governors issued executive orders, or regulatory agencies provided guidance, in some cases tied to general state orders for prevention of the spread of COVID-19, such as limitations on public gatherings, mandatory face coverings in public places, and social distancing, and in others tied to a state’s plans for reopening. Public health agencies issued workplace-specific guidance for occupations posing a high risk of disease transmission. Many of these measures were instituted for a limited period of time, and as the pandemic ebbed in spring 2021, were being phased out or relaxed. California, for example, initially required employers to provide face coverings and ensure that their employees used them under its ETS (Cal/OSHA, 2020a); that requirement was revised on June 17, 2021, when employers were allowed to let fully vaccinated employees forego wearing face coverings indoors (Cal/OSHA, 2021b). Other states issued guidance on which types of masks should be worn by workers based on risk level, even though the requirement for vaccinated workers to wear a mask had ended (Washington State DOLI, 2021b).

Considerations for Voluntary Use of Respirators

In some cases, workers may wear respirators to avoid exposure to a hazardous substance even if that exposure does not exceed the limits set by OSHA standards. Voluntary use of respirators is included within the OSHA Respiratory Protection Standard 1910.134, with requirements specified in Appendix D. The concept of voluntary use of respirators was introduced when OSHA first published its revised Respiratory Protection Standard in 1998; it had not been included in the previous version. According to the revised standard, if “respirator use is not required, an employer may provide respirators at the request of employees or permit employees to use their own respirators, if the employer determines that such respirator use will not in itself create a hazard” (1910.134(c)(2)). As was clarified by OSHA in a letter of interpretation issued on April 26, 2018 (OSHA, 2018), employers are not required to pay for or provide these respirators to employees, but are required to ensure that employees are familiar with the training outlined in Appendix D of the OSHA Respiratory Protection Standard.

Respirators used voluntarily include those that are not filtering facepiece devices and those that are (see Figure 3-2). Under voluntary use, filtering facepiece respirators are not specifically required to be NIOSH approved; they do not require fit testing; employees can have facial hair; and medical clearance is not required (OSHA, 2018), although employees with known respiratory limitations should be advised to consult their physician prior to wearing such a device. “Employers are not required to include in a written respiratory protection program those employees whose only use of respirators involves the voluntary use of filtering facepieces” (1910.134(c) (2)). In contrast, use of elastomeric facepiece respirators or supplied-air respirators, even voluntary use, requires that the employer include all applicable elements in a written RPP to avoid hazards associated with use. The written RPP varies by respirator type selected for use, but must encompass the medical evaluation (which the employer must pay for), cleaning, maintenance, and storage components (OSHA, 2018).

Figure 3-2

OSHA requirements related to voluntary use of respirators in the workplace in the absence of a formal respiratory protection program. SOURCE: OSHA, 2006.

A number of problems can potentially arise when respirators are used voluntarily in the workplace outside of an OSHA-mandated RPP (Gibbs and Nonnenmann, 2020). The use of non–NIOSH-approved devices may occur if employees bring their own devices purchased from retail stores or are unable to obtain approved devices from the marketplace because of shortages. In such cases, the risk is that the protection (e.g., filter efficiency) offered by alternative devices may be untested and insufficient. These devices may have higher breathing resistances relative to approved respirators and cause unacceptable physiological stress to the user. The materials of construction that contact the face of these devices may cause irritation or rashes. Additionally, tight-fitting air-purifying respirators rely on a proper fit to ensure that the majority of air passes through the filter or cartridge and not through facepiece leaks. This assurance normally requires the combination of a fit test to select a proper respirator size and a seal check each time the device is donned. Users who wear respirators in the absence of such testing and/or checking may have a false sense of protection. Despite these concerns, employees’ use of their own personally acquired respirator (i.e., not provided by the employer) may be warranted when employers do not or cannot provide access to protective equipment that is commensurate with the risk to which the workers are exposed (The Joint Commission, 2020).

Underlying the OSHA rules for voluntary use of respirators is the assumption that no significant inhalation hazard is present and that wearing a respirator does not by itself cause a hazard to the user. To ensure that the respirator provides adequate protection and to avoid any device-related problems for the user, the user should have some basic instruction on

• how to don the device properly, including the orientation on the face;
• any limitations of the device for the hazard at hand;
• the need to either dispose of the device after use or properly clean it;
• the need to disinfect the device when worn multiple times in the presence of an infectious agent;
• a proper method for safely storing the device if it will be reused; and
• the requirement that it not have exhalation valves when the hazard is an infectious agent.

Considerations for Voluntary Use of Medical Masks

Medical masks have historically been used to protect others from infectious diseases the wearer may have (source control), and not to provide inhalation protection against hazardous aerosols. Applicable Food and Drug Administration (FDA) regulations (discussed in Chapter 2) govern manufacturers and not employers or employees. Some employers (e.g., hospitals) may have specific rules for their employees governing the selection and use of masks in the workplace. When masks are selected, FDA-cleared devices or those tested to ASTM standards will ensure that the device has an acceptable level of performance in terms of filtration, construction (e.g., biocompatibility), and breathing resistance.

Fit testing is not a requirement for medical masks used in the workplace since the devices are not intended to provide a tight seal to the face of the wearer. However, workers using such masks voluntarily should have adequate instruction on

• how to don the device properly, including the orientation on the face;
• the need to either properly dispose of the medical mask or clean it after use;
• the need to disinfect the mask if the hazard is an infectious agent;
• a proper method for safely storing the device if it will be reused; and
• a requirement that it not have exhalation valves if the hazard is an infectious agent.

Considerations for Voluntary Use of Barrier Face Coverings

Face coverings are an unregulated product that have been widely used to limit the spread of exhaled droplets or fine-particle aerosols during the COVID-19 pandemic. There are no regulations governing the use of barrier face coverings by employers or employees. As discussed above and in Chapter 2, a recent ASTM standard has established requirements for a barrier face covering to be used as a source control product, although the standard does not include a requirement to measure the performance or effectiveness of the product for that purpose. Barrier face coverings are not a substitute for respirators, since their performance in terms of inhalation protection is unknown. However, it may be anticipated that many workers will wear barrier face coverings in the workplace voluntarily even after indoor mask mandates and individual employer policies requiring their use have been lifted, although some may prefer respirators over barrier face coverings once supply issues have been resolved.

Description of the Workforce, Work Environment, and Work Characteristics

Accurately estimating the number of wildland firefighters operating in U.S. states is difficult given the multiplicity of involved organizations and the seasonal variation in numbers (Butler et al., 2017). Organizations engaged in response to wildland fires span volunteer fire departments, municipalities, private contractors, and federal agencies. During extreme fire years, the National Guard or the U.S. military may be asked to respond. During the peak of the 2020 U.S. wildland fire season, 28,000 people (permanent and seasonal employees) were assigned to wildland fire management (NICC, 2020b) in the National Incident Resource Ordering Capability (IROC) system.

The work of wildland firefighters is necessarily strenuous and is carried out under harsh environmental conditions characterized by high heat. The job tasks for wildland firefighters are extremely variable and many require high levels of energy expenditure (Ruby et al., 2002). Most wildland firefighters also camp at the fire location, which can potentially lead to 24-hour smoke exposure. A study by West and colleagues (2020) followed wildland fire resources across the western United States found that 43.2 percent of the firefighters’ shifts was spent in the sedentary activity category, while 47.5 percent was in the moderate/high category (see Table 3-2). The main nonsedentary job task identified by the authors was hiking (19.2 percent). Using GPS trackers, Sol and colleagues (2018) calculated oxygen (VO₂) requirements for different hikes during a shift and quantified the high level of exertion (which can be upwards of 10 metabolic equivalents [METS]) based on terrain and high load carriage (26.6±6.9 kg, 32.7±9.0 percent of body weight). As discussed below, these strenuous working conditions have implications for the kinds of respiratory protective devices that would be suitable for wildland firefighters.

TABLE 3-2

Wildland Firefighters’ Job Tasks Categorized into Four Groups Based on Activity Level and Percentage of Total Person-Task Observations in the Data Set in the Wildland Firefighter Heat Related Illness Study, Western United States, 2013–2016. (more...)

Exposure and Health Impact Data

Wildfires generate a toxic mixture of particulate and chemical vapor inhalation hazards that pose significant risks to the respiratory health of wildland firefighters. Wildland fire smoke has been a concern of the National Wildfire Coordinating Group (NWCG)⁷ since the 1980s (Sharkey, 1997). Studies over the past 30 years have focused on exposure quantification and potential health effects. Wildland firefighters experience other sources of health hazards, such as ground disturbance of silica, combustion engines, and site-specific hazards; in this report the committee focuses on vegetation smoke exposure.

The first study to quantify exposure to wildland fire smoke was conducted by Reinhardt and Ottmar in the early 1990s (Reinhardt and Ottmar, 2004). They found concentrations of carbon monoxide (CO), particulate matter (PM), benzene, formaldehyde, and acrolein, and their initial findings indicated that exposure to all smoke components was higher during prescribed burns compared with wildfires. They also found correlations with increased smoke exposure during higher ambient wind speeds (wind is a critical component of fire growth).

The study by Reinhardt and Ottmar (2004) was limited to a few selected locations on the West Coast. From 2008 to 2011, the United States Forest Service’s National Technology and Development Program (NTDP) conducted a larger-scale follow-up study of smoke exposure to increase the sample size and diversity of fuel models across a larger geographic region of the United States⁸ (Broyles, 2013; Domitrovich et al., 2017). Given the high correlations among smoke components found by Reinhart and Ottmar, this study focused on CO and PM. A novel aspect of this study was that wildland firefighters were trained as research assistants and performed direct observation on potential compounding factors in smoke exposure. The findings of this NTDP study regarding smoke exposure were similar to those of the Reinhardt and Ottmar (2004) study. More recently, Wu and colleagues (2021) studied wildland fire exposure in the Midwestern United States during prescribed burns, finding that the overall exposure levels were higher than those reported in studies of wildland firefighters in the western and southeastern areas of the United States, providing evidence for the role of fuel models and operational tasks in the smoke exposure of wildland firefighters. The authors also reported that no value was over the 8-hour OSHA PEL (Wu et al., 2021).

The NWCG created a task group, which recommended minimizing mop up⁹ and rotating crews out of heavy smoke areas as mitigation measures. This task group also defined a recommended exposure level, taking into account CO, PM, and other smoke components, based on an extended work shift of 16 hours and a 24-hour period, given that a typical wildland firefighter’s shift often exceeds the 8-hour OSHA PEL. Navarro (2020) recently reviewed studies of wildland firefighter exposure to CO and PM and summarized the data in relation to the recommended exposure level and OSHA’s PEL (see Figure 3-3).

Figure 3-3

Summary of particulate matter (PM) and carbon monoxide (CO) concentrations measured on wildland firefighters. These graphs show different levels of exposure to PM and CO captured in a review of relevant studies, and the difference between the recommended (more...)

A large number of studies have examined the health effects of wood smoke, as reviewed recently (Cascio, 2018; Adetona et al., 2016), but only a limited number have focused specifically on wildland firefighters. There have been multiple short-term studies, with time scales ranging from the course of one shift to a whole season, and only one retrospective study on long-term wildland firefighter health. The latter study, conducted by Semmens and colleagues (2016) found two subclinical cardiovascular risk factors (hypertension, heart arrhythmia), as well as markers of musculoskeletal effects (knee surgery), with no other significant health effects. A major limitation of this study, however, was that the questionnaire was sent only to current wildland firefighters and not retirees. Other studies have shown both shift and seasonal changes in respiratory function (Gaughan et al., 2014; Liu et al., 1992). Navarro and colleagues (2019) extrapolated the relative risk of cancer and cardiovascular disease mortality over the course of a wildland firefighter’s career, comparing long (100 days) and short (50 days) fire seasons (see Figure 3-4). These projections suggest the need for more long-term studies to assess the health risks of smoke exposure for wildland firefighters.

Figure 3-4

Relative risk of lung cancer and cardiovascular disease (CVD) associated with length of seasonal wildland firefighting work. Relative risk increases for lung cancer and CVD among wildland firefighters as the daily dose of particulate matter (PM) increases. (more...)

Respiratory Protection and Regulatory Frameworks (Standards, Guidance, and Oversight)

Oversight of use of respiratory protection by wildland firefighters is complicated by the diversity of employment relationships under which wildland firefighters work. Federal wildland firefighters fall under the safety programs of their respective employing federal agencies. Five federal agencies (United States Forest Service, Bureau of Land Management, National Park Service, U.S. Fish & Wildlife Service, and Bureau of Indian Affairs) across two departments (U.S. Department of Agriculture [USDA] and Department of the Interior) have wildland fire management programs. Additionally, each state has its own department of natural resources, and local volunteer and municipality organizations may have responsibility for wildland fire response. The need for respiratory protection for wildland firefighters must be determined by each of these entities.

Respiratory protection has been an area of concern for federal land management fire programs since the Yellowstone fires of 1988. To date, however, no respirator has been found that meets the unique needs of wildland fire management. The strenuous activity associated with wildland firefighting and poor fit due to facial hair are examples of barriers to effective use that could result in a poor face seal and the wearer’s not receiving the intended level of protection (De Vos et al., 2006; Haston, 2007; Sharkey, 1997). Moreover, the impact of breathing resistance on work performance and interference with verbal and visual communications are a concern for firefighters wearing respirators (Beason et al., 1996; Haston, 2007; Reinhardt and Ottmar, 2000; Sharkey, 1997). Additionally, studies by the United States Forest Service’s National Technology and Development Program in the 1990s found that full-face respirators were preferred for all-day prescribed fire activity because of decreased eye irritation. However, the full-face respirators did show increased heat stress, and study participants also reported headaches. Wildland firefighters often use eye irritation as a signal to leave a particular area—a concern also noted in the study (Sharkey, 1997).

Several types of products are marketed to wildland firefighters (e.g., shrouds with filtration devices) but are not NIOSH-approved respirators and have not been studied to validate their protection claims. The National Fire Protection Agency (NFPA) created a wildland fire respiratory performance standard (NFPA, 2022), for the first time in 2011, updated in 2016 and 2022, which outlines the minimal requirements for construction of a wildland fire respirator. NFPA’s current model for such a respirator assumes long-duration, low-concentration exposure; design criteria include being lightweight and small, with easily replaceable filtration pieces. The key air purification required in this document includes carbon monoxide, organic vapors (cyclohexane), sulfur dioxide, nitrogen dioxide, formaldehyde, acrolein, hydrogen fluoride, and hydrogen cyanide. There are three different classes of respirator protection based on the performance requirements. However, no respirators have been designed or tested to the NFPA standard (Adetona et al., 2016).

A specific section in the USDA Forest Service Manual (FSM 5130, “Self-Contained Breathing Apparatus”) allows for wildland firefighters to be trained on and carry self-contained breathing apparatus (SCBAs) that are compliant with NFPA 1981, the Standard on Open-Circuit Self-Contained Breathing Apparatus (SCBA) for Emergency Services. These devices are not to be used in a wildland fire event; SCBAs may be used only when contaminants cannot be avoided (e.g., fires involving vehicles, dumps, structures, or other nonwildland fuels).

The implementation of an RPP for wildland firefighters would be difficult given the nature of the multiagency coordination of agency-specific policy that would be required, in addition to the challenges related to equipment. Training and education on the effective use of respiratory protection would need to cover hazard assessment and the limitations of respirators for protection from wildfire smoke. For example, use of respirators designed to filter particulates without the aid of a CO dosimeter could provide a false sense of security in the field and increase immediate risk to the wearer’s health (Haston, 2007). Administrative oversight and the development of a culture of safety are important for supporting the effective use of respiratory protection for wildland firefighters in the field (Reinhardt and Ottmar, 2000), but may be challenging to achieve in a workforce characterized by a large number of seasonal and volunteer workers.

Limited authoritative guidance is available on the use of respiratory protection by wildland firefighters and their agencies/departments for such hazards as wildfire smoke and infectious respiratory diseases. Federal guidance on the prevention of exposure to wildfire smoke mentions that wildfire-specific PPE should be used, but does not specifically recommend the use of respirators (NIOSH, 2013), and notes that if respiratory protection must be used, once administrative and engineering controls have been exhausted and as determined by the agency/department, it needs to occur within the context of an RPP (Haston, 2007; NIOSH, 2021b; NWCG, 2010). Thus, wildland firefighters face a near total absence of established federal guidance on the use of respiratory protective devices as respiratory protection from wildfire smoke.

In contrast with exposure to wildfire smoke, the emergence of COVID-19 has led to the development of more detailed guidance for this worker population with respect to the use of respiratory protective devices. Authoritative guidance on the use of respiratory protection for wildland firefighters available via the NWCG provides the most comprehensive approach to instituting respiratory protective practices specifically tailored to the needs of this worker group (NWCG, 2021a). However, federal guidance from CDC specific to wildland firefighters has now expired (CDC, 2020b, 2021d), and there has been no clear replacement to address the unique needs of deployed wildland firefighting units (e.g., communal living in bunkhouses, safety of wearing respiratory protective devices, and what devices—respirator or nonrespirator face covering—should be used).

Description of the Workforce, Work Environment, and Work Characteristics

Agricultural workers are a diverse population. Migrant farmworkers in the United States, many of whom come from Mexico and Central America, often serve as field hands to tend to various forms of livestock or harvest a wide range of crops over the course of the growing season. These worker groups are considered vulnerable to health hazards for a number of reasons. The time-sensitive nature of much agricultural work creates pressure on agricultural businesses to maintain work activities despite such environmental risks as extreme heat and poor air quality. Worker literacy and language considerations, including limited proficiency in English and, in some cases, Spanish, can pose challenges for effective worker training and communication regarding hazard identification and controls. Precarious immigration status—whether workers are undocumented or hired through the H2-A visa program—coupled with piece-rate payment schemes common within the industry often serve as disincentives for workers to demand stronger protections from respiratory and other hazards in their work.

Exposure and Health Impact Data

Inhalation hazards for agricultural workers may include inorganic dust from the soil; organic dust containing microorganisms, mycotoxins, or allergens; decomposition gasses; and various chemical agents, including pesticides. Exposures occur when harvesting, dealing with animals, and processing or storing grains or other plant matter, as well as when the soil, plants, or stables are treated with pesticides and disinfectants (Nguyen et al., 2018; Schenker et al., 1998; Viegas et al., 2013).

The need for adequate respiratory protection for agricultural workers has garnered additional attention in recent years in the context of large-scale wildfire events in the western United States (Riden et al., 2020). A recent review of the adverse health effects of such exposures identified risks for asthma, chronic obstructive pulmonary disease (COPD), bronchitis, and pneumonia (Cascio, 2018). Accounts of farmworkers being ordered to continue harvesting crops even as smoke and ash from nearby wildland fires filled the air led worker advocates in California to demand intervention from the California Division of Occupational Safety and Health (Cal/ OSHA), which took the form of a new wildfire smoke standard promulgated as an emergency measure in 2019 and subsequently made permanent in 2021 (NASEM, 2019a).

Respiratory Protection and Regulatory Frameworks (Standards, Guidance, and Oversight)

Overall, few agricultural workers are covered by worksite RPPs (Culp et al., 2004; Greskevitch et al., 2007). This is particularly true for the large population of migrant farmworkers. As mentioned earlier in this chapter, a long-standing congressional appropriations provision has prohibited OSHA from any involvement in farms with 10 or fewer non-family workers (OSHA, 2014b).

The respiratory protection needs of agricultural workers exposed to dusts, molds, and chemicals from farm work are likely to differ in important ways from those of workers incidentally exposed to wildfire smoke. As discussed in Chapter 2, some states in the western United States have recently passed regulations designed to protect workers, including agricultural workers, from exposure to wildfire smoke. In July 2019, Cal/OSHA promulgated a standard requiring employers to institute various control measures when the Air Quality Index (AQI) for PM_2.5 reaches certain thresholds as a result of nearby wildfires (Cal/OSHA, 2021c). The standard includes requirements for respiratory protection: if the AQI for PM_2.5 exceeds 151, employers must provide filtering facepiece respirators and encourage their voluntary use; if the AQI for PM_2.5 exceeds 500, employers must require respirator use, along with mandatory fit testing, if work activities are to continue. Although the Cal/OSHA standard applies to all outdoor worksites, as well as indoor sites without adequate air filtration, a major focus has been on implementation of the standard in agriculture. Similar regulations have been passed in Washington and Oregon (Oregon OSHA, 2021; Washington State DOLI, 2021a).

Few employers in the agricultural industry have had prior experience with respiratory protection as part of their safety practices, and farmworkers often have limited understanding of the functional differences between filtering facepiece respirators and cloth face coverings (Riden et al., 2020). Increased knowledge and understanding of inhalation hazards is an important factor in promoting the use of respiratory protection among agricultural workers, particularly in cases in which hazards emanate from beyond the immediate work processes and procedures (e.g., wildfire smoke, aerosol transmissible diseases). Effective training and communication strategies need to take into account the unique needs and language, literacy, and educational characteristics of this workforce, particularly in the case of migrant and seasonal workers (Basinas et al., 2016; Earle-Richardson et al., 2014; Riden et al., 2020). However, training and education are not sufficient for ensuring proper and consistent use of respiratory protection. Such factors as device discomfort, increased heat load, difficulty breathing, and lost work hours associated with fit testing and medical clearance serve as notable disincentives for individual users (Earle-Richardson et al., 2014; Kusaka et al., 1993; Mpofu et al., 2002; Riden et al., 2020). In the absence of stronger regulatory requirements, employers may be discouraged from instituting RPPs. Larger and better-resourced agricultural operations are likely in a better position to institute such programs (Cramer et al., 2017; Kearney et al., 2014; Syamlal et al., 2013; Virolainen et al., 1987), suggesting the need for both education and resources to incentivize businesses of all sizes to adopt respiratory protective measures for their workers.

In reviewing the gray literature, the committee found several examples of authoritative guidance that addresses the use of respiratory protective devices by agricultural workers for occupational hazards inherent in farm work, as well as incidental exposures such as wildfire smoke and SARS-CoV-2.

CDC guidance specifically for agricultural workers with respect to COVID-19 (CDC, 2021a) has been superseded by universal guidance on mitigation of COVID-19 in workplaces, which is designated for unvaccinated workers or workers who are “otherwise at risk.” Updated OSHA guidance indicates that workers in agricultural processing work settings are deemed to be in this “at-risk” category (OSHA, 2021f). However the general OSHA guidance does not reflect the diversity of job roles and titles captured in the original CDC guidance (e.g., workers on farms vs. ranches), and it is unclear whether the OSHA guidance for at-risk workers is intended to cover the broader category of agricultural workers. Both the now-expired guidance from CDC and the OSHA guidance provide information about the selection, use, and cleaning of respiratory protective devices.

NIOSH has developed guidance on the potential role of respiratory protective devices in controlling exposure to wildfire smoke as part of an RPP (NIOSH, 2021b); however, this guidance does not focus specifically on agricultural workers. Indeed, it appears that no federal guidance specific to this worker group and hazard that supports correct selection and use of respiratory protective devices is available beyond the recommendation to fulfill the components of an RPP. Similarly, guidance developed by Cal/OSHA to support the translation of its wildfire smoke standard into practice is employer focused (Cal/OSHA, 2018). Beyond following the requirements of an RPP once established, workers have little in the way of protection if their employers fail to comply. This gap in user-facing materials and tools for successful integration are addressed through such materials as those produced by the University of California, Davis’s Western Center for Agricultural Health and Safety. These materials, targeted to workers and employers in the region, include training visuals, discussion guides, tools, and checklists designed to support effective implementation in the field (WCAHS, 2021). Such efforts to support the application of standards in the field are essential, but it remains unclear to what degree agricultural workers and employers in areas where wildfire smoke is of concern have access to and utilize these materials and training programs.

One notable exception within the agricultural workers category with regards to having access to respiratory protection and comprehensive guidance on its use is pesticide handlers. Under the authority of the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA), EPA regulations preempt OSHA standards for pesticide applicators. For these workers, EPA administers a worker protection program that mandates respiratory protection. Occupational safety standards implemented under FIFRA to protect agricultural workers from pesticides include the pesticide applicator certification program, as well as the Agricultural Worker Protection Standard. As part of this responsibility, EPA published a guide directed at pesticide handlers (EPA, 1993) that provides guidance for users on different types of respirators and basic information about their use. Additionally, EPA, in coordination with the Pesticide Educational Resources Collaborative (PERC), developed resources to assist employers and business owners in complying with the worker protection standard (PERC, 2017). PERC also has developed and assembled a collection of resources for pesticide handlers and medical professionals that are both specific to respirator use for pesticide exposure (Rutgers University, n.d.) and more broadly pertinent to respirator use in general (NIOSH, 2017b; OSHA, 2011a), designed to support safe and effective use of the devices in the field. Among the guidance available to agricultural workers, that provided to support the use of respiratory protection from standard to application in the field appears to be most complete for pesticide exposures.

Description of the Workforce, Work Environment, and Work Characteristics

Construction firms are overwhelmingly small employers—90 percent employ fewer than 20 people—with limited resources for proper PPE or training for their workers. Small firms represent a disproportionate percentage of construction fatalities (CPWR, 2018) and are more likely than their larger counterparts to hire workers considered at a greater risk for injury, including young workers, those who are less educated, and immigrants (Belman and Levine, 2004; NIOSH, 2015c). One study found that the communication of safety and health information to subcontractors was twice as common in larger (500+ employees) than smaller (1–9 employees) firms (Jones, 2016).

Construction is second only to agriculture in the numbers of foreign-born and temporary workers employed. Approximately 30 percent of construction workers are Hispanic (compared with 17.7 percent of workers in all industries) (Brown et al., 2020), and 15.5 percent are employed by temporary agencies, which adds complexity to determining who is responsible for worker training (CPWR, 2018).

In 2016, the construction industry had a higher rate of union representation than all other industries combined (15.5 percent versus 11.7 percent), although union participation among trades varies significantly (CPWR, 2018). Union membership is an important factor in the safety and health protection of construction workers. Building trade unions integrate safety and health training into their apprenticeship programs to ensure that a solid safety culture is part of the transition from apprentice to journeyman, irrespective of trade. The Center for Construction Research and Training (CPWR) (2018) and Dodge Data and Analytics conducted a survey in 2017 using Dodge’s member contractor panel of roughly 3,000 construction firms, 334 of which participated, and found that union firms

• reported better performance of safety management and safety culture;
• were more likely to be aware of and practice Prevention through Design (a major NIOSH initiative);
• adopted more of the organization safety practices, safety policies, and safety culture indicators considered important by the researchers; and
• were more likely to offer and require general safety and health training and OSHA 10-hour and 30-hour courses for their workers (Wang et al., 2018).

Exposure and Health Impact Data

Inhalation hazards are common in the construction sector. A longitudinal survey of U.S. adults over age 50 showed that the proportion of respiratory cancer–related deaths for workers whose longest-duration job was in construction trades was nearly double that for white-collar workers. Additionally, construction workers were approximately twice as likely to die of nonmalignant respiratory diseases compared with white-collar workers (CPWR, 2018; Wang et al., 2016). The risk of death from lung cancer associated with 5 years of work in the construction industry was comparable to the risk associated with a personal or family history of cancer or a diagnosis of COPD (Dement et al., 2020). Over a 45-year working life, 16 percent of construction workers develop COPD and the lifetime risk of an occupational disease is 2–6 times greater in the construction trades than in nonconstruction work (Ringen et al., 2014).

The onset of the COVID-19 pandemic presented new challenges for construction workers because they were deemed essential workers and could not work from home (NIOSH, 2021a). Construction worksites presented increased risks because multiple trades were forced to coordinate their efforts, often on sites with tight footprints and work practices that required person-to-person interactions, rendering social distancing difficult. Although much of this work can be done outside, projects eventually require working indoors where ventilation may be limited, particularly in cold winter months when heating is a higher priority than circulating outside air (Araya, 2021). Valuable guidance has been developed to improve ventilation on construction sites to prevent the spread of COVID-19 (CPWR, 2021b); research on the implementation of this guidance is needed prior to another pandemic.

A recent study looking specifically at COVID-19 risk factors in the construction sector found about 60 percent of the workers had at least one underlying factor—such as heart or lung disease, diabetes, or being 65 or older—that put them at elevated risk of serious health outcomes or death (Brown et al., 2020). Another study found that the observed relative risk of hospitalization from COVID-19 among construction workers compared with other occupational categories among adults aged 18–64 was 4.9 (95 percent confidence interval [CI], 3.8–6.2). The authors identify construction as a high-contact industry and describe its association with a higher level of community transmission of the disease and larger health disparities among racial and ethnic minority groups (Pasco et al., 2020).

Respiratory Protection and Regulatory Frameworks (Standards, Guidance, and Oversight)

Construction workers may have access to respirators, but they tend to be filtering facepiece respirators without accompanying training. A 2003 BLS survey showed that just under 10 percent of construction workers were required by their employer to use a respirator during a 12-month period (CPWR, 2007), and only half of those employers provided them with the training mandated by OSHA. The BLS survey indicated the respirators most commonly used in construction were for protection against paint vapors (44.7 percent), solvents (27.8 percent), and silica dust (24.1 percent). Where respirators were required, N95 FFRs and other disposable dust masks, which do not provide protection for the wearer against exposure to vapors and solvents, were used most frequently (77.8 percent), and elastomeric half-mask respirators were required for fewer than half of the tasks examined (40.5 percent). In the committee’s analysis of data from federal OSHA violations related to 1910.134(c)(1) issued January 1, 2015–December 31, 2020 (see Appendix A), construction was the second most commonly cited industry.

Several federal agencies, labor unions, and professional associations provide guidance for the construction workforce on a variety of inhalation hazards, including SARS-CoV-2. CDC guidance for construction workers on COVID-19 (CDC, 2021c,j) has expired and been replaced by general OSHA guidance (2021f), which does not use the term “construction worker” and is oriented to any workers who are not vaccinated or are vaccinated but working in higher-transmission areas. OSHA also supplies a page with dedicated guidance on the use of cloth face coverings that provides information for both employers and construction workers on selection, use, and care of these devices in the context of construction work settings (OSHA, 2021a). Labor unions and nongovernmental organizations have taken an active role in calling for and providing details on COVID-19 exposure control by employers, including the use of respiratory protective devices (CPWR and NABTU, 2020; LHSF, 2021). CPWR and North America’s Building Trade Unions (NABTU) standards for construction sites, updated in April 2020 in response to the COVID-19 pandemic, recommend the use of a fit-tested respirator as part of an established RPP, but notes that some local circumstances (e.g., recommendations by local governments or supply issues) may necessitate the use of cloth face coverings (CPWR and NABTU, 2020).

The committee identified just one example of federal guidance for exposure to wildfire smoke that is inclusive of construction workers (NIOSH, 2021b). Additionally, as described earlier in the section on agricultural workers, some guidance is available for employers in California to assist in their compliance with the wildfire smoke standards (Cal/OSHA, 2018), although the committee found no supportive user-oriented guidance during a search for additional guidance materials for this worker population.

Description of the Workforce, Work Environment, and Work Characteristics

The day laborer workforce in the United States is composed largely of immigrant workers hired by homeowners, business owners, and small contractors on a short-term basis to carry out any number of construction, gardening and landscaping, and property maintenance tasks. A 2006 nationwide study of day laborers estimates that on any given day, 117,600 individuals were either looking for day labor jobs at street corners, curb-sides, and hiring centers, or working as day laborers (Valenzuela et al., 2006); numbers now are surely higher.

Employment relations for this group are characterized by temporary and informal work arrangements with few written contracts, and payments often made in cash (Riley and Guzman, 2017). Limited English-language proficiency and lack of authorized or permanent immigration status further contribute to the precarious circumstances of these workers (Fussell et al., 2018).

In addition to the standing day labor workforce, researchers have recently turned their attention to the role played by day laborers as “second responders” in the context of disaster response and recovery (discussed further in the section below on disaster response and recovery workers). Communities devastated by hurricanes, floods, wildfires, and other disasters have often seen an influx of day laborers in the weeks and months following disaster events, as immigrants and other contingent workers have sought jobs on cleanup and reconstruction projects (Cordero-Guzman et al., 2013; Costirilos, 2019; Delp et al., 2009; Fletcher et al., 2006; IDEPSCA, 2020; Theodore, 2017, 2020). Property owners, developers, and contractors, in turn, have come to rely on the ready availability of low-wage workers to serve as the backbone of disaster recovery efforts (Fussell et al., 2018).

Exposure and Health Impact Data

The occupational hazards and work-related injuries faced by day laborers often mirror, in both frequency and severity, those of workers performing comparable tasks under more conventional work arrangements (Burgel et al., 2015; Riley and Majano, 2021). The tasks performed by day laborers—particularly those working in postdisaster settings—may put them at risk for exposure to any number of inhalation hazards, including vapors from paints or solvents; mold, lead, or asbestos; wildfire ash; and dust and debris.

Respiratory Protection and Regulatory Frameworks (Standards, Guidance, and Oversight)

RPPs for the day labor workforce are effectively nonexistent. The informal and short-term nature of most assignments, particularly when workers are hired by homeowners, means that OSHA standards and enforcement generally do not apply. Meanwhile, workers’ reluctance to turn down dangerous assignments because of economic necessity and their lack of hazard awareness have led to little pushback from workers and little incentive for employers to invest in PPE or other forms of hazard control. In this context, the onus has largely fallen on worker advocates to educate these workers and encourage employers to take appropriate protective measures. Pilot projects to train workers on inhalation hazards and to distribute PPE through local worker centers have shown positive results in terms of raising workers’ hazard awareness and encouraging more frequent use of protective equipment, such as N95 FFRs (Contreras and Buchanan, 2012). And in the absence of formal RPPs, a number of day labor hiring sites around the country have taken the lead in offering training and fit testing for these workers, and negotiating with would-be employers on working conditions and use of adequate protections.

Federal guidance on respiratory protection specifically targeting the day labor workforce are nearly nonexistent. While general federal guidance, such as that from NIOSH on exposure to wildfire smoke and outdoor workers (NIOSH, 2021b), may be applicable, these workers are unlikely to be employed in a situation in which an RPP is established. The committee identified no other guidance on other inhalation hazards addressing use of respiratory protection by day laborers or targeted employers of these workers.

Description of the Workforce, Work Environment, and Work Characteristics

Consistent with the scope of the committee’s charge, this section addresses only those health care and allied health workers who would not be expected to be covered by a permanent RPP.¹⁰ These include home care workers, clinicians in solo private practices, dentists, and long-term care workers. Particularly warranting attention are those workers in informal settings who have no formal employers, including those who may be funded through state or local offices on aging through dual Medicare/Medicaid programs but are considered to have been hired by the client or the client’s family.

Many of the nearly 2 million homebound adults over age 65 in the United States may rely on informal family caregivers as well as home care workers provided through state and federal support (Ornstein et al., 2015), and as of 2020, 2.5 million U.S. adults were living in nursing homes or residential care facilities (Scales, 2020). Home care workers (including home health workers and personal care attendants) are disproportionately older women of color. Half have more than two chronic illnesses, nearly half live in households with incomes below $30,000, and nearly half are Medicaid recipients themselves (Bercovitz et al., 2011; Muramatsu et al., 2017). These paid home care workers are not consistently considered to be part of a health care team (Reckrey et al., 2020). Nursing assistants working in nursing homes and long-term care facilities are predominantly (92 percent) females of color and are younger than the average home care worker, with a workforce median age of 37 and 20 percent of workers being under the age of 24. The average nursing home assistant earns $13.38 per hour and $22,200 annually, and nearly 36 percent of this workforce requires public assistance because of these low earnings (Scales, 2020). Dental hygienists provide primary oral health services in dental offices, public health clinics, schools, and nursing homes, among other locations; 226,400 dental hygienists are currently employed in the United States (ADHA, 2021) and are predominantly female (IOM, 2009). Little is known about the demographics of health care workers working in small or private practices, given the breadth of the fields of practice and the wide geographic area in which they work.

Exposure and Health Impact Data

Home care Although systematic data and studies are lacking, home care workers who are not part of a home care agency are vulnerable to inhalation hazards, in part because of limited legal protections (home care work is considered a domestic service in some states and therefore is excluded from basic health and safety protections) (Nasol and Francisco-Menchavez, 2021), and as seen during the COVID-19 pandemic, because of such factors as limited access to respirators, limited provision of training, and lack of any formal organizational preparedness and employer support (Gershon et al., 2010). In a study comparing work–life experiences of agency and nonagency home care workers, agency workers reported receiving significantly more training and supervision compared with nonagency workers (Benjamin and Matthias, 2004). A qualitative study of 33 home care workers (home health and personal care aides and home attendants) revealed that these workers received inadequate respiratory protection support during the COVID-19 pandemic, in part because of PPE shortages. Moreover, these workers did not feel that their essential front-line work during the pandemic was recognized; rather, they felt “invisible” (Allison et al., 2020; Sterling et al., 2020). In another study, 86 percent of 384 respondents had received no training specific to performing their job functions during a pandemic, and just 5 percent reported that their employer had an established pandemic plan (Gershon et al., 2010). Additionally, access to training does not translate to effective use of respiratory protective devices. In this same study, just 16 percent of home health care workers surveyed had received a respirator from their employer; of these, fewer than 72 percent had received training on how to use the device, and only 28 percent had been fit tested on the device (Gershon et al., 2010). And as discussed earlier, in addition to this lack of training and lack of access to fit-tested respiratory protective devices, use of these devices can be associated with discomfort, including difficulty breathing and feelings of overheating, as well as challenges with visual and verbal communication, issues that are perceived as a barrier to effective patient care (Gershon et al., 2010; Mojtahedzadeh et al., 2021). Furthermore, home health aides and personal care aides include a significantly higher proportion of immigrant workers compared with some other health care occupation categories; and immigrant workers are known to be disproportionally negatively affected by COVID-19 (Gelatt, 2020).

Long-term care Long-term care settings, which include nursing homes (1,300,000 residents in the United States) and assisted living facilities (800,000 residents) (Harris-Kojetin et al., 2019), have always been vulnerable to many health care safety hazards, including inhalation hazards (Nasol and Francisco-Menchavez, 2021). COVID-19 had a disproportionately negative impact on this health care sector, with a significantly higher positivity rate for both residents and care professionals, leading to transmission between unprotected care professionals and residents and across nursing home facilities. Although representing only 1 percent of the U.S. population, long-term care facilities have been linked to 4 percent of COVID-19 cases and 31 percent of deaths nationwide (The New York Times, 2021). As of September 2021, more than 136,500 residents and more than 2,070 care professionals in nursing homes had died from COVID-19 (CMS, 2021).

Care professionals who work in assisted living facilities experience similar safety problems, including inadequate protection against inhalation hazards. Assisted living facilities have notoriously failed to comply with wage and labor standards (Shah, 2017), and concerns about their inadequate preparation for a potential pandemic were reported well in advance of COVID-19 (Lum et al., 2014).

Care professionals working in dentistry settings Dentistry entails the use of rotary dental and surgical instruments (e.g., hand pieces or ultrasonic scalers and air-water syringes), which can aerosolize saliva, blood, microorganisms, and other debris. Given the unique nature of dental practice, which requires professionals to operate very close to the patient’s mouth, the risk of aerosol transmission of infectious agents is high (Clementini et al., 2020; Gandolfi et al., 2020; Zemouri et al., 2017, 2020). A New York Times article titled “The Workers Who Face the Greatest Coronavirus Risk” identifies dentists and dental hygienists as more at risk than any other health care workers, including nurses, personal care aides, and general practitioners (Gamio, 2020).

Other care professionals in small or solo private practices Despite closures and telehealth-based alternatives, health care workers in solo practices have been disproportionately affected by COVID-19 (Rubin, 2020). An investigation of 1,004 COVID-related deaths among health care workers globally as of May 13, 2020, for example, found a significantly higher proportion of deaths from COVID-19 occurring among physicians who practice family medicine or primary care (general practitioners) (Gouda et al., 2020).

Respiratory Protection and Regulatory Frameworks (Standards, Guidance, and Oversight)

Inconsistent compliance with recommended guidelines for respirator use has long been a major problem in health care. NIOSH conducted a 2011 web-based survey of more than 10,000 health care workers who routinely use or are exposed to certain chemical agents (including nurses, pharmacy practitioners, technologists/technicians, anesthesia care professionals, respiratory therapists, and dental care professionals) in the United States (Wizner et al., 2018). Only 18 percent of respondents surveyed reported using a respirator as protection against chemical agents, of which 24.9 percent reported being fit tested for the respirator they used. When respondents were asked about their respiratory protection practices when potentially exposed to 1 of the 10 specific airborne hazards on which the survey focused, their responses varied widely (see Figure 3-5). The high percentage reporting use of a surgical mask when working with these specific airborne hazards raised concerns about inappropriate use of these masks in lieu of respirators (Wizner et al., 2018).

Figure 3-5

Respiratory protection practices for health care workers exposed to airborne hazards. This bar chart shows how the use of respirators and surgical masks and the use of no device vary by respondent across exposures to different types of hazards, indicating (more...)

When the survey participants who reported not using a respirator when potentially exposed to one of the 10 aerosol hazards were asked about their reason for not following the recommended respiratory protection practices, factors related to organizational characteristics were found to play a major role: respirator use not part of the local protocol (32 percent of responses), exposure perceived as minimal (21 percent), respirator not provided by employer (12 percent), respirator not readily available in work area (11 percent), no other colleague or peer in the workplace using it (10 percent), and engineering control being used (8 percent). Furthermore, job characteristics (i.e., job type, involvement with direct patient care) and worksite characteristics (number of employees) were found to be predictive of appropriate respirator use. Specifically, those employees working in large organizations (number of employees >1,000) reported significantly greater respirator use when potentially exposed to one of the 10 specific aerosol hazards compared with those working in smaller organizations (<100 employees). On the other hand, characteristics of individual health care workers (e.g., age, education level) were not a significant predictor of respirator use, a finding consistent with those of other studies (Hines et al., 2014; Nichol et al., 2013). These findings are consistent with and highlight the importance of (1) a systems approach to respiratory protection and (2) a human-centered approach to respirator design to improve and sustain appropriate use.

The Hospital Respiratory Protection Program Toolkit was developed in 2015 by NIOSH to address these challenges and the need for a coordinated systems approach to incorporate respiratory protective device use into the hospital setting (NIOSH, 2015b).

The vast majority of health care workers in the United States, including those who work in states with OSHA-approved State Plans that do not provide this protection or those in states with federal OSHA programs, are not covered by a specific, formal, permanent aerosol transmissible disease standard. Such standards are currently under development and have been adopted by a number of states. Although these standards are necessary for prevention, existing risk assessments related to the pandemic suggest that all health care workers—from clinicians performing aerosol-generating procedures; to clinicians in general; to clerical, environmental services, dietary, security, and other support staff in hospitals, nursing homes, and other long-term care facilities or in home care—may need to be included in full formal RPPs under OSHA’s Respiratory Protection Standard. Such programs need to extend to employees in private medical or dental offices as well, and to be strongly encouraged for self-employed practitioners. OSHA’s ETS for workers in health care settings, while temporary, represented an important step forward in addressing this need. Many of these health care and allied health worker groups are also a focus for OSHA’s National Emphasis Program, which targets inspections to high-hazard industries so as to better ensure that employees in those industries are protected from contracting COVID-19 (OSHA, 2021c).

Government underregulation of long-term care and assisted living facilities has been identified as a major factor in these facilities serving as “hot spots” for COVID-19 (Nasol and Francisco-Menchavez, 2021). As opposed to nursing homes, which are regulated at the federal level, assisted living facilities are regulated at the state level, and thus they vary greatly as to infection prevention and control requirements. Viral outbreaks are a major problem in these facilities because of gaps in infection prevention and control programs, written procedures, and training, so that staff have inadequate knowledge about appropriate respiratory protection (Bamberg et al., 2013; CDC, 2020a; Kossover et al., 2014).

Limited authoritative guidance is available that directly focuses on workers in long-term care and assisted living facilities with respect to the use of respiratory protective devices for COVID-19. However CDC definitions of health care workers are inclusive of these worker groups, so they can be encompassed by broader guidance for workers and employers in health care settings, such as CDC’s interim guidance on infection control in health care settings (CDC, 2021e). State-level guidance, such as California’s Interim Guidance for Protecting Workers at Skilled Nursing and Long-term Care Facilities, also exist, providing a structure for employers’ expansion of respiratory protection for these groups (Cal/OSHA, 2021a).

Few small or solo private health care practices (such as those in family medicine, internal medicine, and pediatrics) have adequate infrastructure or resources for providing safe care during a pandemic, such as COVID-19, or have any formal RPP. Similarly, a substantial proportion of dental care professionals in the United States work in the private sector, half in solo practice, without a formal RPP (ADA, 2021), although in the wake of the COVID-19 pandemic, one might plausibly expect a substantial increase in the establishment of RPPs that comply with OSHA regulations among dental care practices (OSHA, 2021b). Yet, while some federal guidance is available for health care practitioners in small practices, such as dentists (OSHA, 2021b), to aid with such efforts, most of the available guidance is oriented to larger health care settings.

Description of the Workforce, Work Environment, and Work Characteristics

The COVID-19 pandemic and the 2009 H1N1 pandemic have demonstrated the importance of respiratory aerosol transmission to a wide range of public-facing workers, including teachers, wait staff, day care providers, public transportation workers, janitors, and workers in correctional facilities and homeless shelters, among many others. Those working in close proximity to others, such as in manufacturing and food processing, also have experienced high rates of worksite transmission. Ancillary personnel (e.g., Transportation Security Administration [TSA] workers in airports, USDA inspectors in meat and poultry processing plants) may be exposed as well. During the COVID-19 pandemic, many previously public-facing workers were able to work remotely, while others, chiefly in the hospitality industry, lost their jobs. However, large industry sectors, including housing construction, agriculture and food processing, energy, utilities, transportation, manufacturing, security, and others, were declared “essential,” exempted from stay-at-home orders, and continued to work with inadequate respiratory protection. Many of these workers lacked paid sick leave and faced job loss for missed work, exacerbating the risk of disease transmission.

Exposure and Health Impact Data

During the H1N1 pandemic, differential increases in absences due to illness (Tora-Rocamora et al., 2012), in hospitalizations, and in mortality were identified among different industry and occupational categories, as well as among different racial and ethnic groups, indicating occupational risk (Luckhaupt et al., 2012). Tora-Rocamora and colleagues (2012) identified the health, education, and social services sectors as seeing the earliest and sharpest rise in illness-related absences relative to other industry sectors. Comparison of the occupational categories of hospitalized adults with confirmed influenza in 10 U.S. states with the proportions employed in those sectors using the National Health Interview Survey revealed disproportionate representation among workers in transportation and warehousing, administrative support, waste management and remediation services, health care, and accommodation and food service (Luckhaupt et al., 2012). The H1N1 pandemic also saw disparities by race, ethnicity, and socioeconomic status in self-reported influenza-like illnesses and increased household disease transmission associated with lack of available sick leave (Kumar et al., 2011).

Variation in COVID-19 impacts by industry and occupation Compared with the H1N1 pandemic, the current COVID-19 pandemic has been much more lethal for workers, although failure to capture surveillance data by industry and occupation for COVID-19 infections and deaths in the United States (with the exception of health care workers) has severely limited understanding of the pandemic’s toll. The press has consistently outpaced public health agencies in identifying important trends, ranging from health disparities to worksite outbreaks (Jordan and Dickerson, 2020).

Despite limitations of the available data, some data are available on the differential impacts of COVID-19 by industry/sector:

• Early data from six Asian countries suggested excess infections among health care workers, drivers and transport workers, services and sales workers, cleaning and domestic workers, public safety workers, and religious professionals, with increases among different groups appearing at different times (Lan et al., 2020).
• In California, workers in the health care, facilities, food and agriculture, government and community, manufacturing, retail, transportation, and logistics sectors experienced significantly increased mortality risk ratios; again, different industries peaked earlier or later in the pandemic in this regard (Chen et al., 2021).
• Washington State reported COVID-19 infection and hospitalization rates disproportionate to employment levels in the food processing, air transportation, residential services, merchants/wholesalers of nondurable goods, justice/public safety, agriculture, and health care sectors (Wuellner, 2021). In some instances, worksites concentrated exposures, contributing to community outbreaks.
• Occupational information available for 555 death certificates among those aged 16–64 dying from COVID-19 documented excess rates in the health care support; transportation and material moving; food preparation and serving; building and grounds cleaning and maintenance; production; construction and extraction; installation, maintenance, and repair; protective service; personal care and service; arts, design, entertainment, sports, and media; and community and social service sectors (Hawkins et al., 2021).
• Finally, the Council of State and Territorial Epidemiologists recently adopted exposure criteria for classifying occupational transmission of COVID-19 based on Department of Labor O*NET work designation for three risk factors—public-facing work, working indoors, and working in close proximity (Council of State and Territorial Epidemiologists, 2021).

Characteristics of work and the workforce that increase risk and vulnerability include exposure to infectious aerosols among those not able to work remotely; lack of appropriate occupational safety and health protections, including training; densely populated, poorly ventilated, or enclosed work spaces; prolonged face-to-face or physical contact where social distancing is not practiced; demographic characteristics; comorbidities; and coexposures (Carlsten et al., 2021). Individuals working in grocery stores and pharmacies exemplify essential workers who would be expected to experience prolonged exposures to the public, with little or no safety and health precautions in place and significant socioeconomic and demographic challenges. An investigation of COVID-19 rates in a Massachusetts grocery store in May 2020 found that 20 percent of the 104 workers screened by polymerase chain reaction (PCR) testing had positive viral assays; fewer than 50 percent of the workers who tested positive were symptomatic (Lan et al., 2021). COVID-19 infection rates among grocery workers represented by a local United Food and Commercial Workers Union (UFCW) in the mid-Atlantic region were lower than background county rates for those stores in which managers implemented a variety of safety measures, including enforced mask use by customers (CRowell et al., 2021). In one of the earliest and most devastating outbreaks of COVID-19 identified among U.S. workers, employees in meat and poultry processing plants demonstrated an extraordinarily high risk not only for infection and death but also for seeding of community outbreaks. Based on incomplete data reported by 30 states through May 31, 2020, CDC identified 8,978 infected workers across 742 agricultural and food processing worksites, with 55 deaths (Waltenburg et al., 2021).

Transportation issues arose early in the pandemic, with cruise ships and a U.S. aircraft carrier reporting explosive outbreaks (Kasper et al., 2020), and deaths among bus drivers and other transportation workers being reported through news media and transit unions. By April 9, 2020, at least 33 New York City transit workers had died from COVID-19, with bus drivers being disproportionately impacted (Martinez, 2020).

Some of the highest COVID-19 infection rates were seen among public safety and correctional workers. As of April 21, 2020, an incomplete U.S. sampling revealed COVID-19 infections among 4,893 inmates and 2,778 corrections personnel, including 88 and 15 fatalities, respectively (Wallace et al., 2020). By November 24, 2020, Colorado had reported a total of 204,000 COVID-19 cases, including 15,526 hospitalizations and 2,821 deaths, among incarcerated individuals (Quan et al., 2021). Following compassionate early release, a project in Colorado found 4 of 165 formerly incarcerated individuals to be infected, as well as 4 of 20 staff working in community organizations assisting with community reentry (Quan et al., 2021). A seroprevalence study of SARS-CoV-2 antibodies in New York City identified the highest rate among correctional staff (39.2 percent seropositive), with traffic officers, security guards, firefighters, and others with first responder or security responsibilities having elevated rates as well (Sami et al., 2021). Furthermore, among 37,640 Federal Bureau of Prisons staff, SARS-CoV-2 infection was most prevalent among staff in institutions where social distancing by staff and inmates was limited (Toblin et al., 2021).

Workers and volunteers in homeless shelters have long been aware of respiratory transmission of tuberculosis and other infectious diseases. In March 2020, outbreak investigations at three King County, Washington, homeless shelters identified COVID-19 infections among 18 percent of residents and 21 percent of staff members (Tobolowsky et al., 2020). A subsequent cross-sectional study of 14 King County homeless shelters found a 2 percent infection rate by PCR testing; of 157 staff tested, 4 tested positive (Rogers et al., 2020).

Variation in COVID-19 impacts by race, ethnicity, and socioeconomic status Employees designated as “essential” and unable to work remotely are disproportionately low-wage racial and ethnic minorities (Hawkins, 2020). Black workers, for example, make up approximately 26 percent of public transit workers but just 11.9 percent of the total working population, while Hispanic workers constitute 40.2 percent of workers providing building cleaning services despite representing only 16.8 percent of all U.S. workers (see Table 3-3). The failure to protect large groups of these workers contributed to their widely disproportionate experience of infection and mortality from COVID-19 relative to other population groups. The demographics of the essential workforce are presented in Table 3-3, from the Center for Economic and Policy Research (Rho et al., 2020). The differential occupational exposures of these workers contributed to widespread infection among multigenerational households in populations with high rates of preexisting conditions associated with the social determinants of health, compounded by a lack of access to appropriate health care.

TABLE 3-3

Characteristics of Workers in Front-Line Industries.

Respiratory Protection and Regulatory Frameworks (Standards, Guidance, and Oversight)

Evidence from the H1N1 pandemic and the severity of outcomes from COVID-19 point to the need for a complete safety and health program adhering to the hierarchy of controls, including a formal RPP, among large sectors of the U.S. workforce currently not likely to be covered by such a program. Employers of health care support, transportation, manufacturing, retail, service, and other workers at increased risk from infectious pandemic agents have a responsibility to provide them safe working conditions. However, this responsibility is not consistently met, impacting not only these workers’ health but also their willingness to perform their job functions during a public health emergency. Organizational preparedness that includes enforcing existing safety and health protections, as well as providing access to respirators and developing and implementing formal RPPs, among other measures, is necessary to ensure worker safety and willingness to work (Gershon et al., 2010). Misclassification of transportation, cleaning, and other workers as self-employed results in large numbers of workers for whom safety and health protections are lacking. Here again, the primary response required is adequate enforcement of existing Department of Labor protections.

Failure to protect essential workers, including health care workers, marked the first year of the pandemic. Several factors may have contributed to this inadequate protection of workers and the lack of formal RPPs:

• Both WHO and CDC were slow to recognize and acknowledge the significant role of airborne transmission of SARS-CoV-2 by aerosols (Tanne, 2020). As late as July 2020, for example, WHO posted the following statement, effectively dismissing the need for RPPs against aerosols in most settings, except certain medical situations: “Current evidence suggests that SARS-CoV-2 is primarily transmitted between people via respiratory droplets and contact routes—although aerosolization in medical settings where aerosol generating procedures are used is also another possible mode of transmission” (WHO, 2020).
• Early on, the United States experienced a widely reported and acknowledged shortage of PPE, including respirators (CRS, 2020).
• Throughout the first year of the pandemic, OSHA failed to respond adequately to worker complaints about hazardous working conditions or enforce its Respiratory Protection Standard in settings characterized by SARS-CoV-2 exposures (Whoriskey et al., 2020).
• U.S. labor laws and changing hiring practices have contributed to a workforce with large numbers of at-will workers,¹¹ an absence of paid sick leave, and workers in informal working arrangements, leaving these workers without pathways for negotiating for basic safety and health protections, such as RPPs (Kumar, 2011; Quinlan, 2021).

Thus, for the vast majority of essential workers, meaningful improvements in overall safety and health during pandemics will require enhancing existing mechanisms designed to ensure that work does not endanger the workers or their families and communities.

On the other hand, the genuinely self-employed, such as those offering home day care services or owning very small groceries or laundries, and their employees may fall outside of current regulatory requirements and would appropriately rely on the types of protections available to the public. The same is true of essential workers who are able to socially distance, such as some utility workers, as well as workers in offices where social distancing and improved ventilation are rigorously maintained. The challenge these worksites may present is one of outreach and communication, often complicated by language or other barriers. Efforts to address the needs of the self-employed and small business owners will require specific focus, for example, on the leadership role small business owners may play in the use of respiratory protection (Jones et al., 2021).

While OSHA provides extensive enforcement and outreach guidance for RPPs, CDC/NIOSH, the National Institute of Environmental Health Sciences’ (NIEHS’s) Worker Training Program, and OSHA’s Susan Harwood Training Grant program have developed or funded others to create extensive libraries supporting worker outreach and training (CDC, 2021f,h,i; NIEHS, 2021; OSHA, 2021i). A number of unions, educational institutions, nonprofit organizations, and worker centers have collaborated with end users to develop training for both workers and small businesses (CPWR, 2021a; SEIU, 2021). CDC maintains several occupation-specific guidance documents, including new or updated guidance for restaurant and bar operators, in-home social service providers, public transportation operators, and airline crews, which include links to general guidance on types of respiratory protective devices and their use (CDC, 2021b,g,k,l). OSHA guidance is available for small business owners who are required to establish an RPP to address occupational exposures that necessitate respiratory protection (OSHA, 2011a), but this guidance is not intended for use by employees and does not address the needs of all workers at increased risk of exposure to infectious agents. Future health communications about respiratory protection would benefit from clear messaging that is appropriate to workers’ literacy levels (Pan et al., 2020). Moreover, research into improved respirator design is necessary to address the needs of workers who must communicate with the public while using a respirator; to assess the potential for respirator contamination under various use scenarios; to improve comfort, ease of use, and the ability to communicate during use; and to identify, evaluate, and determine how best to implement approaches to encouraging correct use.

Description of the Workforce, Work Environment, and Work Characteristics

Various workers may be engaged in different phases of the disaster cycle (see Figure 3-6). The initial rescue phase of any disaster involves immediate action by responders to save lives. With the transition to the recovery and cleanup stage, other types of workers are brought in.

Figure 3-6

Evolution of health and safety risks across the phases of a disaster. This figure illustrates the transition from one phase of a disaster to the next and how risks to workers evolve with the transition between phases. SOURCE: Courtesy of Bruce Lippy, (more...)

Construction workers are routinely pulled into disaster responses of all types. During the cleanup at the World Trade Center, for example, nearly all of the building trades were onsite: heavy equipment operators moved debris, ironworkers cut beams and rigged loads, electricians rerouted phone and electrical lines, laborers moved debris and sealed contaminated areas, carpenters built barriers, and teamsters hauled debris in large articulated dump trucks. Most of these workers had no training in disaster response and received no site safety and health training until 78 days after the towers had fallen (Lippy, 2002). Operators of heavy equipment are regularly pulled into much smaller disasters, such as house collapses or flooding, when the first hours are critical to saving lives.

Day laborers have also been engaged in response and recovery efforts for many disasters over the past two decades, including

• the attacks on the World Trade Center in 2001 (EHS Today, 2002);
• Hurricane Katrina in 2005 (Delp et al., 2009; Fletcher et al., 2006);
• Hurricane Sandy in 2012 (Berger, 2012; Cordero-Guzman et al., 2013);
• Hurricane Harvey in 2017 (Theodore, 2017); and
• California wildfires, including the Thomas Fire in 2017, the Woolsey Fire in 2018, and the Camp Fire in 2018 (Costirilos, 2019; IDEPSCA, 2020).

Of note, day laborers have increasingly been engaged in both wildfire first response and recovery/cleanup efforts (Costirilos, 2020).

Volunteers from the public are another important population of workers during most disaster responses. They often are the first on the scene to respond to car crashes and house fires or to save neighbors during floods or wildfires, and are the primary rescuers of fellow citizens from collapsed buildings (Macintyre et al., 2006). Even among firefighters, volunteers greatly outnumber professionals: the NFPA estimates that of the total number of firefighters in the United States in 2018, 67 percent were volunteers (Evarts and Stein, 2020).

Volunteers often feel compelled to help during major disasters, as was the case with the many volunteers who helped serve food to responders at the World Trade Center through such organizations as the Red Cross, which also deployed an estimated 220,000 volunteers to hurricanes Katrina and Rita (American Red Cross, 2006). And many spontaneous volunteers show up at disaster sites with no affiliation, just a desire to help. Sauer and colleagues (2014) sought to understand the use of volunteers in disasters by surveying 24 of the 51 total member organizations in National Voluntary Organizations Active in Disaster (VOAD). Among those organizations, 79 percent reported regularly using spontaneous volunteers during disasters, and 68 percent found these volunteers to be useful (Sauer et al., 2014), although they were rarely credentialed, and only half (53 percent) of the organizations provided them with training.

Exposure and Health Impact Data

Workers engaged in the response to or recovery from disasters often work at uncontrolled sites where the hazards are not fully known. In the initial response phase, there is often a “risk a life to save a life” mindset. It is critical to delineate clearly when the rescue phase has concluded and the disaster has shifted to a more controlled recovery phase, during which the hazards may still be present but the pace can be slowed and the work shifts reduced, allowing responders to catch up on sleep and meals, which also reduces their risk; the key is to recognize that the longer the rescue phase continues, the greater is the risk. Yet, the shift from rescue to recovery operations is not always apparent, as was the case during the World Trade Center response, in which the rescue phase was reportedly extended through June 2002 for the entire 9 months of debris removal operations (Newman, 2013) even though the last survivor had been rescued on September 12 (Cloud, 2002). The Federal Response Plan that was in effect during the response assigned OSHA the role of making “available safety and health specialists to provide safety-specific assistance to affected disaster response agencies as required by the Federal Coordinating Officer” (FEMA, 1999, p. 260). However, enforcement was limited, and once workers were onsite, there was little leverage for ensuring compliance, and as a result, respirator use was documented as inconsistent (Lippy, 2002). Eventually, a disaster site can transition to a nearly normal construction site (see Figure 3-6), although risks to workers at the site may still be elevated. Three aspects of disaster recovery greatly increase the likelihood that construction workers will confront risks to health and safety:

• “the rapid pace at which recovery operations are undertaken, including working long hours and without necessary rest breaks;
• the prevalence of multiple hazards at any given worksite; and
• the fact that hazards may be unknown to work crews that are entering a worksite.” (Theodore, 2017, p. 8)

Inhalation hazards in disaster scenarios can include ash and debris, mold, asbestos, and other airborne contaminants, depending on the nature of the disaster (Delp et al., 2009). And as discussed at length above, in the case of wildfires, exposure to wildfire smoke has been associated with respiratory symptoms, as was the case, for example, with day laborers and domestic workers who reported breathing difficulties following the Woolsey fire (IDEPSCA, 2020).

Respiratory Protection and Regulatory Frameworks (Standards, Guidance, and Oversight)

Disaster response and recovery workers are a diverse population whose respiratory protection needs may differ. Studies of past disasters have shown that different types of disaster workers may be more or less likely to use respiratory protection, highlighting the need for improved training, selection, fit testing, and consistency in use for respiratory protection among emergency responders (Antao et al., 2011).

An important factor impacting the respiratory risks to workers engaged in response and recovery efforts are the changes to regulations that may occur during disaster conditions. In some cases, OSHA standards and enforcement operations may be suspended in disaster-affected areas, removing incentives for employers to provide adequate protections (Fussell et al., 2018). The Army Corps of Engineers, often involved in disaster response and recovery, has its own regulations (EM385 manual), which are similar to OSHA’s.

Construction workers Inadequate use of respiratory protection by construction workers at the World Trade Center is a well-documented problem. Fit testing was not widely available until more than 1 month into the disaster response. More than 100,000 elastomeric half-mask respirators were distributed but compliance with their use was routinely poor: operators of heavy equipment working in the restricted zone generally wore their elastomeric half-mask respirators less than 50 percent of the time (Lippy, 2002). In contrast, compliance with respirator use was reported to be around 90 percent at the Fresh Kills site where the debris was taken, an operation managed by the Army Corps of Engineers, which was effective at getting workers to wear respiratory protection during the World Trade Center cleanup effort (DePalma, 2006).

OSHA’s Hazardous Waste Operations and Emergency Response (HAZWOPER) standard (1910.120) clearly stipulates the training needed for each type of responder, and specifically allows construction workers to have less training relative to other responders. Under 1910.120(q)(4), the agency identifies “skilled support personnel” as

personnel, not necessarily an employer’s own employees, who are skilled in the operation of certain equipment … and who are needed temporarily to perform immediate emergency support work that cannot reasonably be performed in a timely fashion by an employer’s own employees and who will be or may be exposed to the hazards at an emergency response scene.

These skilled support personnel are not required to meet employers’ training requirements for regular employees, merely to receive an initial briefing at the worksite before beginning response work. The briefing must include instruction in the wearing of appropriate PPE but can be of any length. The assumption is that workers deemed skilled support personnel will be onsite only briefly during the emergency phase and, if staying when the site transitions to cleanup activities, would then receive appropriate HAZWOPER training. However, this assumption proved incorrect during the World Trade Center response. To remedy this deficit, OSHA, working with safety and health representatives of the building trades unions, developed two OSHA Disaster Site Worker courses (OTI 7600 and OTI 5600) that are now delivered across the country. Both are voluntary, however, and it has proven difficult to convince construction employers of the need to have their workers trained in anticipation of a disaster.

An overlooked and rarely cited requirement in the HAZWOPER standard is 1910.120 (o) which requires employers to “develop and implement procedures for the introduction of effective new technologies and equipment for the improved protection of employees working with hazardous waste clean-up operations, and the same shall be implemented as part of the site safety and health program to assure that employee protection is being maintained.” This requirement is essentially acknowledging the position of respiratory protection at the bottom of the hierarchy of controls and promoting more effective strategies. Limited but noteworthy efforts were made to implement control technologies at the World Trade Center cleanup (Lippy, 2003).

Day laborers Despite the increasingly frequent role of day laborers in disaster response and recovery efforts, employers often fail to provide them with PPE or training, let alone other aspects of an effective RPP (e.g., fit testing, medical clearance), and respiratory problems may result (Delp et al., 2009). In one study day laborers reported access to key types of personal protective equipment, such as respirators, but in many cases these devices were being used long after their effective use period had ended (Delp et al., 2009). In other cases, workers reported trying to protect themselves by tying a t-shirt over their mouth and nose or otherwise trying to prevent exposure to health hazards (Theodore, 2017). For example, most of the workers involved in recovery and cleanup activities at the World Trade Center site were day laborers performing tasks such as removal of asbestos. Many of these workers describe not being given training on the hazards faced and not being provided with any type of respiratory protection or protective clothing (EHS Today, 2002). Likewise, only 18 percent of day laborers in New Orleans after Hurricane Katrina reported having access to respirators (Fletcher et al., 2006). More than 60 percent of day laborers (nearly two-thirds) surveyed during the Hurricane Harvey cleanup had no respirator; many used inadequate equipment or simply covered their noses and mouths with t-shirts. Given the unpredictability of the specific conditions that will be encountered by second responders involved in post-disaster cleanup at a worksite, it is incumbent on employers to provide appropriate PPE, including respiratory protective equipment to their crews (Theodore, 2020). Making safety and health training for day laborers in disaster areas a priority is essential, as is providing them with PPE.

Volunteer disaster response and recovery workers Disaster volunteers routinely show up at disaster sites without PPE, such as respiratory protective devices, or knowledge of the risks they face, which places strains on the existing response infrastructure (Van Hoving et al., 2010). Among the tens of thousands of responders at Ground Zero, for example, spontaneous volunteers carried water to the heavy equipment operators on the smoking pile of debris at the World Trade Center unaware of the hazards to which they were being exposed.

From a risk standpoint, there is a great difference between affiliated and unaffiliated volunteers. The latter population receives little or no training for the most part and does not understand critical safety issues. It is not surprising then, that 42 percent of the volunteer organizations reported injuries and two fatalities among their volunteer responders (Sauer et al., 2014). The researchers concluded that while the use of spontaneous volunteers is widespread, nongovernmental organizations are “not necessarily structured to incorporate them effectively. More structured efforts to integrate [spontaneous volunteers] are critical to safe and effective disaster response” (Sauer et al., 2014, p. 65).

NIEHS’s Worker Training Program has been a major force in protecting this vulnerable population, providing training in worker safety and health in disaster response to more than 20 grantees for more than 20 years. This adaptable training infrastructure is based on experience in training workers responding to Ground Zero, the Gulf oil spill, wildfires, and hurricanes and allows for just-in-time development of materials for future disasters (Rosen et al., 2015). In 2020, the Worker Training Program collaborated with the American Industrial Hygiene Association (AIHA) to develop user-oriented guidance for volunteers on COVID-19 prevention practices in response to growing concerns about infection-related health risks for volunteers (AIHA, 2020). Additionally, NIEHS (2013) has developed mold remediation guidance oriented toward disaster recovery volunteers and essential workers, providing them with detailed information about the selection and use of respiratory protection and other types of PPE.