Inspection and Maintenance for Aircraft Fire Extinguishers

Fire extinguisher inspection and maintenance is the best way to keep your safety equipment in peak working condition. Your aircraft’s fire extinguishers need testing at different times, so you must understand your equipment’s demands and file detailed maintenance records. Trusting a repair station that complies with regulatory bodies such as the Federal Aviation Administration for your servicing is vital for accurate results.

The Value of Extinguisher Maintenance and Inspections

The Code of Federal Regulations requires all aircraft to contain extinguishers in the cabin, crew and cargo compartments. These extinguishers must undergo inspections at the proper intervals to ensure serviceability and immediate readiness.

A well-maintained extinguisher prepares you to protect your crew and passengers in an onboard emergency, while complying with industry regulations.

Each part of an extinguisher must be in good working condition for it to work effectively. That’s why timing is essential. When conducting preventive maintenance checks, professional technicians have the skills and training to spot wear, damage and potential malfunctions that you might miss.

Aircraft Fire Extinguisher Inspection Requirements

Service intervals can vary based on the type of extinguisher you have. To ensure your fire extinguisher is in excellent shape, you must meet fire extinguisher testing requirements set by the Department of Transportation or your equipment’s manufacturer. Here are the intervals to pay attention to.

Monthly Checks

You should visually inspect your extinguisher at least once each month. Check the equipment for the following signs of damage:

  • Corrosion
  • Cracks
  • Leaks
  • Dents

Look at the extinguisher’s pressure gauge to determine if the internal pressure is within the equipment’s operating range. If you find surface damage or notice that the pressure is outside the operating range, contact a qualified technician at an FAA repair station to service or replace your extinguisher.

Annual Inspections

Aviation fire extinguishers require an annual external check. More thorough than a monthly inspection, this involves a trained technician checking these components:

  • Cylinder
  • Seals
  • Hose and nozzle
  • Pressure gauge
  • Safety pin
  • Instruction label

During this check, the technician also weighs the extinguisher to ensure it contains the full extinguishing agent amount.

Five-Year Re-Hydrostatic Testing

DOT 4D and 4DS cylinders, such as cargo, APU and engine extinguisher bottles, require servicing every five years. These frangible and hermetically sealed bottles require re-hydrostatic testing to ensure structural integrity. This type of testing checks an extinguisher’s ability to withstand high internal pressure, which can fail if damage or corrosion develops. During a hydrostatic test, a professional technician pressurizes the cylinder beyond its regular operating pressure and checks for signs of damage.

Six-Year Internal Inspection

Portable fire extinguisher manufacturers typically recommend a mandatory internal inspection every six years, which can vary based on your extinguisher brand. Internal inspections involve the following checks and services:

  • Emptying the extinguisher
  • Inspecting its internal components for wear or damage
  • Reassembling the internal and external components
  • Refilling the extinguisher with a new agent

12-Year Inspection

In-cabin portable dry-chemical fire extinguishers usually require system service every 12 years, depending on manufacturer recommendations. Similar to the five-year hydrostatic test, a 12-year hydrostatic test checks the cylinder’s structural integrity. During this test, a technician pressure-tests the cylinder and carefully looks for signs of damage.

How to Keep up With Fire Extinguisher Inspection and Maintenance

Stay prepared for in-flight emergencies with the following maintenance and inspection tips.

  • Check the manufacture date: If your extinguisher has gone without maintenance for an extended period, find its date of manufacture on the nameplate’s lower right-hand corner to determine when it’s due for inspection. For example, an extinguisher manufactured in 2020 is probably due for a six-year inspection in 2025. Otherwise, you can start by scheduling monthly and annual inspections.
  • Track maintenance and inspections digitally: While you can record maintenance and inspections on an extinguisher’s tag, digital records increase accuracy, accessibility and searchability. With a digital system, you can set reminders for inspection intervals and automate your scheduling processes.
  • Trust an experienced service provider: Work with an experienced extinguisher maintenance provider to ensure they follow the proper procedures for testing and repairs. Your chosen provider should comply with a certifying regulation such as the FAA, European Union Aviation Safety Agency or Air Transport Canada.
  • Follow proper shipping and handling procedures: Depending on your location, you may need to ship your fire extinguisher for service. Follow the proper safety precautions for shipping and handling fire extinguishers to ensure safe transport. For example, you must pack cylinders in strong non-bulk external packaging, heat the inner packaging to achieve the proper pressure and mark the outside of the packaging to indicate its contents.

Common Fire Extinguisher Repairs

When a technician finds damage or a malfunction, they may address it with one or more of the following repairs.

  • Cylinder replacement: If cracks, corrosion or dents impact an extinguisher’s structural integrity and effectiveness, you may need a replacement.
  • Nozzle replacement: Cracked or obstructed nozzles can hinder agent discharge. If you notice visible damage on the nozzle, contact a technician as soon as possible to determine if a replacement is necessary.
  • Recharging: Technicians remove a cylinder’s extinguishing agent and refill it. Discharging and recharging replenishes and repressurizes the extinguisher so it’s ready for a crisis.
  • Pressure gauge irregularities and leak solutions: If your pressure gauge or TCPS is outside its operable range, a technician may need to replace the extinguisher or replace the faulty components and overhaul the extinguisher, as these can be welded into the bottle.
  • Seal replacement: A seal replacement is necessary if this component is leaking.
  • Cartridge/Squib replacement: Cartridges or squibs used on engine, APU, and cargo bottles carry their own expiration dates, stamped on the side of the cartridge, these are required to be replaced every 6 to 10 years, depending on the manufacturer.

Stay Prepared With HRD Aero Systems’ Aviation Fire Extinguisher Testing Services

Fire extinguishers are crucial for aircraft safety, and regular inspections help ensure they are in top shape. HRD Aero Systems provides aviation fire extinguisher testing to help you comply with regulatory standards and maintain your aircraft’s safety.

We comply with certifying regulations such as the FAA, EASA and Air Transport Canada. As an FAA repair station, we can test and approve your extinguishers for safe use, ensuring they are in peak working condition. We offer fast turnaround times and competitive pricing to streamline your inspections. Contact us to schedule extinguisher testing or learn more about how we can prepare your safety equipment for emergencies.