All fittings for medical gas work shall be kept separate from other tools, and kept free of grease or oil. If cleaned, only a degreaser such as ____________ is permitted.

• A. Trisodium phosphate or sodium carbonate
• B. Water
• C. Goop or GoJo hand cleaner
• D. A natural citrus solvent cleaner-degreaser

Answer: (A)

In medical gas work, fittings must be kept free of oils and greases because even small residues can ignite or contaminate the gas, especially in oxygen-rich environments. Cleaning with an approved degreaser ensures oils are removed and leaves minimal, controllable residue after rinsing. Trisodium phosphate or sodium carbonate are effective, water-soluble cleaners that break down oils and can be thoroughly rinsed away from metal fittings, making them appropriate choices. Plain water won’t reliably remove grease, so it isn’t sufficient. Hand cleaners like Goop or GoJo contain oils and waxes that could leave residues and become ignition sources or contaminate the system. Natural citrus solvent cleaners can be flammable and may leave hydrocarbon residues, which is undesirable in gas systems. Therefore, a degreaser such as trisodium phosphate or sodium carbonate is the appropriate option.