Fire-extinguishing agents

This regulation specifies which fire-extinguishing agents airlines can use in their aircraft systems. Only methyl bromide, carbon dioxide, or agents proven equally effective are permitted.

If the airline uses methyl bromide or another toxic agent, the system must be designed to prevent harmful concentrations of fumes from entering passenger or crew areas—both during normal operations and if the extinguisher discharges due to a system malfunction on the ground or in flight. Methyl bromide containers must be filled with dry agent and properly sealed by the manufacturer or qualified recharger using approved equipment.

For carbon dioxide systems, the design must ensure that even if the system discharges, not enough CO₂ can enter occupied compartments to create a suffocation hazard.

In practice, this means airline fire suppression systems must balance effective fire protection with crew and passenger safety, preventing toxic exposure or oxygen displacement in areas where people are located.

*This is a plain-English summary for study only. The official 14 CFR text on this page is controlling — always read the current regulation and consult a CFI.*