What percentage of alcohol-resistant foam is recommended for use on polar solvent fires?

• A. 2% or 4%
• B. 3% or 6%
• C. 5% or 7%
• D. 1% or 10%

Answer: (B)

The recommended concentration of alcohol-resistant foam for use on polar solvent fires is typically in the range of 3% to 6%. This type of foam is specifically formulated to be effective against polar solvents, which can include a range of substances like alcohols and ketones that are miscible with water.

Using an alcohol-resistant foam at this concentration helps to create a stable and effective foam blanket on top of the burning liquid, preventing ignition of the vapors and allowing for effective suppression of the fire. Concentrations outside this range may not provide the same level of protection and effectiveness in controlling fires involving polar solvents, which can be more challenging to extinguish than non-polar solvents due to their chemical properties.

Therefore, the choice indicating 3% or 6% is aligned with standard practices and guidelines in firefighting for mitigating polar solvent fire hazards.