Compressed gas cylinders can be used in a variety of laboratory applications. The hazards involved are both mechanical and chemical. The chemical hazards are dependent on the type of gas used. Flammable gasses and oxygen increase the risk of fire or explosion. Reactive or toxic gasses increase the risk of poison. Even inert gasses, like nitrogen, can increase the risk of asphyxiation if there is a leak.
All gasses under pressure are explosive hazards. They can become missiles if the valve or cylinder is breached.
All compressed gas cylinders are permanently labeled. Cylinders should be marked “full”, “in use”, or “empty” with tags. Each type of gas has a standard cylinder value to prevent mixing of incompatible gasses. The thread and diameter of the connections vary and they can be either right-handed or left-handed. All connections should be inspected to ensure they correspond and are undamaged. Some connections may require washers.
Some general safety rules to remember when using compressed gas cylinders are listed below.
- Always turn the gas off when not in use.
- Always release the pressure in the gas system before removing regulator or other connections.
- Test for leaks in all joints and connections with soapy water prior to use. Bubbles indicate leaks.
- Safety cap should be on during transport or when not in use.
- Always secure cylinders to prevent tipping.
- Don’t roll or drag cylinder. Always use proper hand truck with safety chain.
- Never store oxygen cylinders near flammable gas cylinders.
- The valve and regulator on an oxygen tank must be free of oil or grease. Oil in contact with oxygen or other oxidizers can be explosive.
- Never ride on elevator with compressed gas or liquid nitrogen.