Which combination of chlorine concentration and immersion time is used for field sanitizing of mess gear?

• A. 25 ppm for 30 seconds
• B. 100 ppm for 120 seconds
• C. 50 ppm for 60 seconds
• D. 10 ppm for 10 seconds

Answer: (C)

For field sanitation of mess gear, the sanitizer must be strong enough to kill microbes but still practical to use in a field setting. The recommended approach is a chlorine solution with about 50 ppm available chlorine and a 60-second immersion. This combination provides reliable microbial reduction on clean, hard surfaces without the extra residue or prolonged exposure that would be unnecessary in most field situations.

Lower concentrations or shorter times won’t reliably sanitize, such as a weaker solution for 30 seconds. Higher concentrations or much longer immersions, like 100 ppm for 120 seconds, aren’t typically needed in this field context and can be more cumbersome or harsh on gear. A very low concentration like 10 ppm for 10 seconds simply isn’t enough to achieve proper sanitization.