Compressed gas cylinders are routinely filled and used safely across various industries, provided that established procedures are followed to recognize and mitigate associated hazards. The safe handling and filling of these cylinders—especially with flammable gases—require strict adherence to applicable federal, state, provincial, and local regulations. Personnel involved in these operations must be well-versed in these regulatory requirements. Additional compliance measures apply to medical and food gases, which are addressed in separate CGA publications.
This publication describes the recommended industry practices and precautionary measures for filling cylinders with certain liquefied and nonliquefied flammable industrial, medical, and food gases and mixtures containing these gases. It should not be assumed that every safety precaution is included here. This publication does not cover equipment design specifications to perform these filling operations.
This publication covers the filling of flammable gases in high pressure seamless and low pressure welded cylinders. These include but are not limited to DOT-3A, DOT-3AA, DOT-3AL, DOT-3E, DOT-4B, DOT-4BA, DOT-4BW, DOT 39, and corresponding Transport Canada (TC) equivalents. Additionally, flammable gases may be filled in authorized UN/ISO cylinders and composite overwrapped pressure vessels (COPVs). It addresses the filling of these cylinder design specifications individually or in bundles or cylinder banks. This publication is not intended to serve as a standard operating procedure (SOP) for filling operations.
This publication does not address automated or palletized cylinder filling operations.
This publication does not cover the filling of portable cylinders from one cylinder to another, commonly known as transfilling. This does not exclude the addition of mixture components when filling cylinders.
This publication does not cover the filling of:
• Liquefied and nonliquefied nonflammable industrial, medical and food gases, such as air, argon, carbon dioxide, helium, nitrogen, nitrous oxide, and oxygen; and
• Specialty gases, acetylene, or liquefied petroleum gases.
The requirements for filling of these gases are addressed in other CGA publications.