out in strict compliance with procedures established to assure safety of flight and mission completion. This section establishes procedures and re- quirements for the quality control of gaseous oxygen that is stored, transferred, and used for breathing purposes by aircrews. This section is applicable to all personnel who are responsible for supervising or performing the operations as- sociated with and servicing of the aircraft with aviators breathing oxygen. Quality Control Requirements of Gaseous Oxygen The procurement limits for purity and con- tamination, which include the absence of odor, of aviators gaseous breathing oxygen must meet the requirements of the current issue of MIL- O-27210. The on-station monitoring of aviators gaseous breathing oxygen for contamination is performed by a sniff odor test. WARNING The odor test is very hazardous due to the high pressure in the cylinder. Do not place your face or nose directly into the venting gas stream and do not take deep breaths. Discontinue “sniffing” any gas at the first indication of irritation of the nasal pas- sages or at any sign of physical discomfort. Some contaminants are extremely irritat- ing, poisonous, or toxic, and can cause physical injury. The odor test can only be performed safely if the procedures are followed exactly. NOTE Persons temporarily unable to detect or classify odors because of head colds, hay fever, etc.,   must be excluded from the assignment of inspecting for the presence of odorous contaminants. If an odor is detected, discontinue the inspection process. When detected, an attempt should be made to classify it, such as “acrid,” “sweet, ” “rotten egg,” “glue like,” etc., as this will help in the identification of the source of the contaminate. Gaseous Oxygen Servicing Trailer Gaseous oxygen servicing carts must be sampled and tested whenever contamination is suspected or after the completion of any maintenance action performed on the cart. An odor test must be conducted prior to servicing any aircraft system. This is accomplished by opening slightly the valve at the terminal end of the recharging hose and smelling the escaping gas in accordance with the procedures described in the A6-332AO-GYD-000. If an odor is present, the servicing cart will not be used to service the aircraft. Each cylinder must be inspected for the following: . Proper painting and marking. l Valves are tightly closed and not leaking. l Safety caps and safety plugs are secure. . Hydrostatic test date is current. . All valves, manifold, servicing hose, and cylinders are clean and free of grease and oil. The presence of any grease or oil on the valves or cylinders must be reported to the maintenance officer for necessary action, and the servicing cart must be placed in a contaminated status. HIGH-PRESSURE AIR Using high-pressure compressed air safely requires knowledge and skills. Despite all the safety programs and posters regarding this shop hazard, reports of fatalities and serious injury from this cause continue to accumulate. High-pressure compressed air is provided from one of three sources: 1. A portable high-pressure cylinder 2. A cascade-type servicing trailer equipped with several cylinders 3. Direct service from a portable high-pressure air compressor Each of these sources is no less dangerous than the precautions already discussed for handling oxygen cylinders. Precautions apply generally as well for the handling and stowage of compressed air cylinders. Do not fill any cylinder with a gas other than that gas for which the cylinder has been specifically designated. Explosive mixtures may 1-6