Table G.1Sodium hypochlorite: concentration and use

Starting solution
Most household bleach solutions contain 5% sodium hypochlorite (50 000 ppm available chlorine).
Recommended dilution
1:100 dilution of 5% sodium hypochlorite is the usual recommendation. Use 1 part bleach to 99 parts cold tap water (1:100 dilution) for disinfection of surfaces.
Adjust ratio of bleach to water as needed to achieve appropriate concentration of sodium hypochlorite. For example, for bleach preparations containing 2.5% sodium hypochlorite, use twice as much bleach (i.e. 2 parts bleach to 98 parts water).
Available chlorine after dilution
For bleach preparations containing 5% sodium hypochlorite, a 1:100 dilution will yield 0.05% or 500 ppm available chlorine.
Bleach solutions containing other concentrations of sodium hypochlorite will contain different amounts of available chlorine when diluted.
Contact times for different uses
Disinfection by wiping of nonporous surfaces: a contact time of ≥ 10 minutes is recommended.
Disinfection by immersion of items: a contact time of 30 minutes is recommended.
N.B. Surfaces must be cleaned of organic materials, such as secretions, mucus, vomit, faeces, blood or other body fluids before disinfection or immersion.

ppm: parts per million

From: Annex G, Use of disinfectants: alcohol and bleach

Cover of Infection Prevention and Control of Epidemic- and Pandemic-Prone Acute Respiratory Infections in Health Care
Infection Prevention and Control of Epidemic- and Pandemic-Prone Acute Respiratory Infections in Health Care.
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