According to NFPA 407, how high must extinguisher identification lettering be for visibility?

• A. 2 inches
• B. 3 inches
• C. 4 inches
• D. 5 inches

Answer: (C)

The National Fire Protection Association (NFPA) 407 gives specific guidelines regarding fire safety for airport refueling vehicles, and part of this includes the visibility requirements for extinguisher identification lettering. For effective visibility in emergency situations, the standard mandates that the lettering used to identify fire extinguishers must be at least 4 inches high. This size ensures that personnel can readily identify and access fire extinguishers quickly when responding to an incident, even from a distance or in low-light conditions. Having identification lettering of appropriate height plays a critical role in maintaining safety protocols at airports, where rapid response to fire emergencies is crucial.