What is one of the steps in the preflight check for the Lav fire extinguisher on the EMB?

Verifying that the gauge is in the green zone is an essential step in the preflight check for the Lav fire extinguisher on the EMB because it ensures that the extinguisher is properly charged and ready for use in case of a fire emergency. The green zone indicates that the pressure within the extinguisher is adequate; if the gauge is in the red zone, it would signify that the extinguisher may not be functional, either due to being over or under pressurized.

This step is critical for safety, as an uncharged extinguisher would be ineffective during an emergency situation. The preflight check is designed to ensure all safety equipment is operational, providing assurance to crew and passengers alike that adequate fire protection measures are in place.

Other steps may include checking if the inspection sticker is current, ensuring the pin is secure, and confirming the weight of the extinguisher. While these are important for overall safety and compliance, the immediate readiness indicated by the gauge directly affects the effectiveness of the extinguisher in an emergency scenario.