🔍 Key Concepts

• Fixed and portable foam fire extinguishers used on vessels • U.S. Coast Guard foam extinguisher classification A B-I, A B-II, A B-III and how they differ • Typical capacity in gallons associated with each foam class rating

💭 Think About

• First, recall or estimate the usual gallon capacity for smaller A B-I and A B-II foam extinguishers, then compare how much larger an A B-III unit would logically be. • Think about what size extinguisher would be practical for shipboard use: too small and it’s ineffective for a serious flammable liquid fire, too large and it becomes hard to handle. • Consider the relationship between the class rating number (I, II, III) and extinguisher size: does the rating usually increase, decrease, or stay the same as the capacity increases?

✅ Before You Answer

• Verify in your study materials or CFR/USCG prep tables what gallon capacity is listed specifically for an A B-III foam extinguisher. • Double-check that you are not confusing foam extinguishers with dry chemical or CO₂ extinguisher sizes, which use different common capacities. • Confirm that the capacity you choose is realistic to carry and operate by one or two people on board, consistent with typical marine extinguishers.