What chlorine concentration (ppm) is required to disinfect floors, counters, sinks, and toilets at emergency shelters?

• A. 1000 ppm
• B. 500 ppm
• C. 2000 ppm
• D. 750 ppm

Answer: (A)

Disinfection of environmental surfaces needs a chlorine level that reliably inactivates common pathogens on nonporous surfaces found in shelters. A solution with about 1000 ppm available chlorine is routinely used for disinfecting floors, counters, sinks, and toilets in emergency shelters. This concentration provides effective germicidal action against typical shelter contaminants (including viruses and bacteria) while balancing safety and material compatibility.

Practical notes: clean surfaces first to remove dirt, then apply a fresh chlorine solution so the surface remains wet for about five minutes to achieve proper disinfection. Use appropriate PPE, ensure good ventilation, and never mix chlorine with ammonia or acids. This approach aligns with standard shelter disinfection practices, making 1000 ppm the best choice.