For polar solvents and other alcohol hazards, a foam concentrate solution of what percent is required?

• A. 3%
• B. 6%
• C. 9%
• D. 12%

Answer: (B)

Foam concentrates for polar solvents and alcohol hazards must create a strong, long-lasting film that both blankets the spill and suppresses vapors. Because these fuels mix with water and evaporate quickly, a higher concentration is needed to form that protective interfacial film and to ensure good surface wetting and extinguishment. The middle concentration hits the right balance: it provides effective film formation and vapor suppression without the unnecessary drawbacks of using too much foam, such as excessive foam blanket or wasted concentrate. Lower concentrations won’t form an adequate protective film for these hazards, while higher concentrations don’t add meaningful benefit and can complicate application. That’s why the middle option is the best choice for polar solvents and alcohol hazards.