In the publication "Acceptable Methods, Techniques, and Practices," the FAA warns against using "harmful cleaning, polishing, brightening or paint-removing materials" when cleaning aircraft. What is "harmful" depends upon the material the aircraft is made of.
Highly acidic or alkaline cleaning agents, such as fluoride- or chlorine-based cleaners, should be avoided. They can cause corrosion to different metals of an airplane, leading to hydrogen embrittlement, or weakening of the metal parts. The FAA suggest using only materials recommended by the aircraft's manufacturer and cleaning agents that are "relatively neutral and easy to remove," such as Earth Soap or FlightBright.
Wipes or cleaning agents used on an airplane should not be volatile. Natural fiber cleaning cloths are preferred by the FAA. Cleaning agents should also be kept away from open flames and live electrical circuits.
Cleaning agents used on the interior of an aircraft should not affect the flame-retardant capability of seats and other upholstery. Material that is treated to be flame-retardant should not be washed with water, since the chemicals used to make it are water-soluble. Soap should not be used on most flame-retardant fabrics either, as it will break down the chemical finish.
Dry-cleaning solvents, water-free detergents or other cleaning products recommended by the manufacturer should be used on flame-retardant fabrics.
Cleaning agents and solvents should not be mixed, as this may create an agent that can damage airplane parts or be flammable.
The amount of cleaning agent used should follow manufacturer's recommendations. Using a higher level than recommended could damage aircraft parts such as tires and cables. These parts should be cleaned with a cloth lightly coated with the cleaning agent.
The FAA warns not to use ammonium hydroxide on the wings of a plane or expose the wings of a plane to this cleaning chemical.
Certain previously acceptable cleaning solvents including methyl chloroform and trichlorotriflouroethane, while still used to clean some avionics, are being phased out as aircraft cleaners since they are pollutants and possibly cancerous. Replacement cleaning products should be thoroughly tested to ensure they do not damage aircraft parts and systems, according to the FAA.
