Foam concentration shall be within what percent of acceptable test results?

Foam concentration shall be within what percent of acceptable test results?

• A. 5 percent
• B. 10 percent
• C. 15 percent
• D. 20 percent

Answer: (B)

Foam performance depends on keeping the concentrate dilution within a tight, known range. The requirement sets a tolerance of plus or minus ten percent around the acceptable test result, so the actual concentration must be between 0.9 times and 1.1 times the target value. This balance reflects typical measurement and mixing variability while ensuring the foam maintains its intended expansion, spreading, and burn-protection characteristics. If the tolerance were tighter (like 5%), it would be harder to meet in practice; if looser (15% or 20%), foam performance could drift enough to reduce effectiveness. For example, with a target concentration of 3%, acceptable results fall between 2.7% and 3.3%.

Foam performance depends on keeping the concentrate dilution within a tight, known range. The requirement sets a tolerance of plus or minus ten percent around the acceptable test result, so the actual concentration must be between 0.9 times and 1.1 times the target value. This balance reflects typical measurement and mixing variability while ensuring the foam maintains its intended expansion, spreading, and burn-protection characteristics. If the tolerance were tighter (like 5%), it would be harder to meet in practice; if looser (15% or 20%), foam performance could drift enough to reduce effectiveness. For example, with a target concentration of 3%, acceptable results fall between 2.7% and 3.3%.