What component should be regularly checked for proper operation in extinguishers?

Regular checks of the pressure gauge on a fire extinguisher are crucial for ensuring that it is in proper working condition. The pressure gauge indicates whether the extinguisher has sufficient pressure to effectively discharge its contents when needed. A gauge reading in the green zone signifies that the extinguisher is properly pressurized, while readings in the red zones (either low or over-pressurized) suggest that maintenance or service is required. Monitoring the pressure gauge is a primary safety measure, as an extinguisher that is not charged correctly may fail during an emergency, rendering it ineffective.

Other components, although important, do not serve the same critical role in indicating whether the extinguisher is operational. For instance, while the hose must be checked for blockages or damage, and the handle needs to be functional, these aspects don't directly inform users about the readiness of the extinguisher. The inspection label is also significant as it tracks service dates and inspections, but it does not impact the immediate operational readiness indicated by the pressure gauge. Thus, regular monitoring of the pressure gauge remains the most reliable method for ensuring a fire extinguisher is prepared for use.