Air Compressor Safety 101

Number one hazard for compressed air? Hose and fitting pressure. An air compressor running at 400 PSI exerts a considerable outward force on hoses and valves. At pressures that can exceed 45,000 lb, an air compressor can generate more thrust than that produced by a Boeing 747. In addition to the pressure it generates, the amount of energy a compressor stores can also be extremely dangerous.  

All air compressors are equipped with an air/oil separator tank or pressure vessel and all vessels are equipped with a pressure safety valve (PSV). Make sure that the appropriate PSV is installed with a relief pressure that is below the maximum rated pressure of the vessel and piping. You’ll find this information on the data plate that is mounted on the pressure vessel. Also, sometimes local authorities require that pressure vessel and relief valves be registered and/or periodically tested by a third party. Make sure that you comply with these requirements.

When working with pressures of up to 400 PSI, regularly inspecting all hoses and fittings is extremely important. In addition to pressure, your air compressor generates a dangerous amount of heat. The temperature of the compressed air at the discharge outlet can exceed 200 degrees F. Air hoses are rated for both operating pressure and temperature. Make certain that the hoses you’re using meet the needs of your equipment and your application; that they are rated to meet both pressure and temperature needs. That information can also be found on the data plate.

Be attentive to the condition of the hoses. Old or frayed hoses can cause air leaks, which reduce pressure and lead to machine malfunctions. In addition, a damaged hose can lose pressure and then suddenly re-pressurize, potentially causing damage to the compressor and injury to the operator.

Hose fittings are also components that are critical to safe operation. Know the type of fitting you are using and what is it rated for. Know, too, the maximum working pressure of each fitting and confirm that the retainer pin is installed in order to prevent the fitting from coming apart during operation. Make certain that the hose and fittings mate properly, as not all fitting methods are approved for all hoses.

Then, prior to use, inspect all fittings, checking for the proper settings along with any signs of wear or fatigue. Make sure that the approved hose restraint device is properly installed and working properly. Lastly, remove any hose or fitting that does not meet the maximum operating conditions of the system.  

Maintenance is key to safety, and so is personal protective equipment. Before you operate or perform any maintenance services on an air compressor system, be sure to wear the proper personal protective equipment. Just as importantly, always maintain your compressor “by the book.” Every compressor has a maintenance schedule booklet which you need to follow. Be sure to perform the required maintenance tasks on schedule, follow any controller warnings regarding needed maintenance, monitor oil system levels diligently to avoid the possibility of fire, and never mix fluids such as mineral and synthetic compressor oil. 

Prior to performing any maintenance, make sure that the machine is off, isolated, and that the wheels and tow bars are adequately supported. Depressurize all parts; do not rely on check valves. If performing maintenance shortly after use, be cautious of hot parts and if replacing parts, use only those approved by the manufacturer.

When you’re ready to get started, perform a visual inspection by walking around the machine; look for leaks, loose or missing parts, damaged parts, or parts out of adjustment. Always lock out the compressor’s power source before conducting an inspection or any maintenance services. If fuel, oil, water or DEF need refilling, do so only when the electrical power is off.

In wrapping up, we’d like to offer you just a few tips to keep in mind for safely operating an air compressor:

1. Use only pressure valves built to national or international standard for air receivers and make certain they are certified for use at your intended site.
2. Use heavy duty clamps and fittings made specifically for compressed air hose and verify the type and size of hose based on fittings and connectors
3. Never use hoses that appear to be frayed, deteriorated, or damaged in any way
4. Always store hoses away from direct sunlight and heat
5. Always secure a hose open end in order to prevent injury from “whipping”
6. Per OSHA regulations, make sure that all hoses exceeding ½ in. ID have a safety device at the source of supply or branch line to reduce pressure in case of hose failure
7. Wear protective equipment, including ear protection
8. Always follow the safety and maintenance instructions in the found in the compressor’s Instruction Manual!

A final tip: When it comes to maintenance and safe operation, never guess. Do it “by the book” or better yet, consult with an Atlas Copco professional. Always wear the proper personal protective equipment. And while this is by no means a comprehensive guide, we hope that you now know just a few of the steps you can take to keep yourself, and your fellow workers, safe while working with compressed air.