What is the proper ratio of bleach to water for surface disinfection?

What is the proper ratio of bleach to water for surface disinfection?

• A. 9 parts bleach to 1 part water
• B. 2 parts bleach to 1 part water
• C. 1 part bleach to 3 parts water
• D. 1 part bleach to 9 parts water

Answer: (D)

Choosing a dilution of one part bleach to nine parts water delivers the right balance for surface disinfection. With typical household bleach, this yields about 0.5% available chlorine, which is strong enough to disinfect most common germs on nonporous surfaces while minimizing risk of damage to materials and reducing fumes. It’s important to prepare the solution fresh, apply it so surfaces stay wet for the contact time specified on the product label, and then use as directed (wipe or air dry as recommended). Stronger dilutions don’t significantly increase disinfection benefit and can cause corrosion or irritation, while weaker ones may not disinfect reliably.

Choosing a dilution of one part bleach to nine parts water delivers the right balance for surface disinfection. With typical household bleach, this yields about 0.5% available chlorine, which is strong enough to disinfect most common germs on nonporous surfaces while minimizing risk of damage to materials and reducing fumes. It’s important to prepare the solution fresh, apply it so surfaces stay wet for the contact time specified on the product label, and then use as directed (wipe or air dry as recommended). Stronger dilutions don’t significantly increase disinfection benefit and can cause corrosion or irritation, while weaker ones may not disinfect reliably.