Why should a driver check the fire extinguisher's pressure gauge as part of the pre-trip inspection, rather than just confirming it is present?

Pick an answer

1. Pressure gauge checks are unnecessary as long as the extinguisher is mounted in its bracket, since the bracket itself indicates it's ready for use
2. An extinguisher that is present but not properly charged would fail to work when actually needed
3. Gauge checks are required only once a year during the annual inspection
4. The gauge only needs checking if the extinguisher looks visibly damaged

Correct!

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