🔍 Key Concepts

• USCG fire extinguisher size classifications (Size I, II vs. III, IV, V) • Difference between portable, semi-portable, and fixed fire extinguishing systems • How extinguisher size relates to mounting and method of use on board

💭 Think About

• Think about how a crewmember would physically use a size III, IV, or V extinguisher—can one person easily carry and operate it by hand? • Consider which sizes are typically installed with a bracket and hose, intended to be moved only a short distance rather than worn or carried freely. • Ask yourself which answer choice best matches larger-capacity extinguishers that are still not built permanently into the vessel’s piping or machinery spaces.

✅ Before You Answer

• Review which sizes (I and II vs. III, IV, V) the Coast Guard defines as portable. • Check how the regulations distinguish between semi-portable units and fully fixed systems. • Verify that the option you pick matches the idea of a unit that is larger, often mounted, and sometimes requires more than one person to move.