What should be checked on the H2O fire extinguisher during preflight?

When conducting a preflight check on an H2O fire extinguisher, verifying that the copper seal is intact is crucial. The copper seal ensures that the extinguisher has not been tampered with and is still in a usable condition. If the seal is broken, it may indicate that the extinguisher has been discharged or might not function correctly in an emergency.

Ensuring an unbroken seal is vital for safety, as it gives the operator confidence that the extinguisher is ready for use when needed. The integrity of the copper seal is a common industry practice to assess both the functionality and reliability of fire extinguishers before flight operations. Thus, checking the integrity of the seal aligns with best practices in fire safety equipment maintenance.