If a fire extinguisher pressure gauge shows that the charge is in the red zone, a disposable fire extinguisher should be replaced. If it is a First Alert disposable fire extinguisher that is still under warranty, contact Consumer Affairs at 1-800-323-9005 for warranty service. Please note that you must completely empty the unit before shipping, turn the extinguisher upside down and the agent will run out. Since the unit is no longer pressurized, no shipping precautions are necessary. If any of your rechargeable fire extinguishers show a pressure gauge reading in the red, they should be taken to a local fire extinguisher service business to be recharged and serviced if necessary. If it is a First Alert rechargeable fire extinguisher that is still under warranty, contact Consumer Affairs at 1-800-323-9005. Please Note: If you trigger-test a First Alert fire extinguisher, your warranty will be void.