Which one of the following is a Coast Guard requirement for fire extinguishers?

To ensure safety while boating, having fire extinguishers on board is a crucial requirement established by the Coast Guard. The standard specifies that fire extinguishers must be maintained in a fully charged and usable condition. This means they should be regularly inspected to check for pressure and operational readiness. A fire extinguisher that is not fully charged may fail to function effectively in an emergency, leading to dire consequences. Keeping the extinguisher in a state of readiness exemplifies responsible boating practices and compliance with safety regulations.

The other options are related but do not meet the specific requirements set forth by the Coast Guard. For instance, storing extinguishers under a seat might not ensure immediate accessibility when needed. Regular replacement is not strictly mandated every two years, but rather depends on the manufacturer's guidelines and condition. Painting extinguishers bright red may aid visibility; however, it is not a requirement for compliance. Therefore, maintaining extinguishers in a fully charged and usable condition is key to ensuring safety on the water.