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When compared to other pieces of equipment on a working jobsite, an air compressor hardly seems hazardous. How can air be dangerous?
"Think of compressed air as stored energy," says Tom Grau, product-line R&D department manager with MMD Equipment. "Consider it takes almost nine cubic feet of air to make one cubic foot of compressed air, and you get some idea of the energy that is stored, not only in the air compressor's tank but also in the hose connected to the tools you're operating.
"This energy did not get compressed easily," he continues. "For a 185-cfm machine, it takes over 50 hp at 3,000 rpm to confine that energy. Therefore, the sudden, uncontrolled release of this energy could have devastating results."
This is why your customers need to take note and pay attention to the industry's safety rules for compressed air. But first, before the compressor even leaves your rental yard, there are some items you need to check.
Initial inspections
According to Harold Wagner, national sales manager with Kaeser Compressors, the compressor, air hose and air tools need to be inspected thoroughly. Here are some items that need to be checked:
Compressor
- Check for the correct tire pressure and excessive tread wear; improperly inflated tires can affect road handling, damage the tire and make transportation dangerous.
- Ensure that shutdown devices and pressure and temperature gauges are working.
- Check that all lights are working properly.
Air Hose
- Use an air hose rated for the maximum compressor pressure and flow.
- Do not allow your hoses to be run over by vehicles or stored improperly; cracks or weak spots are not only wasteful, but also dangerous to the operator.
- Make sure that the hose and compressor discharge fittings match; always use the safety pin to prevent the fittings from disconnecting — if a pressurized air hose breaks loose, "fish tailing" could injure workers and damage equipment.
- Depressurize the hose prior to disconnecting.
Air Tools
- Inspect all air tools to ensure proper operation; make sure all components are tight and that no parts are missing or damaged.
- Consult your tool steel catalog for proper tool steel selection and application.
- Check air pressure to ensure proper working pressure of the tool.
- Always purchase the best air tool lubricant available to prolong equipment and tool steel life.
In addition to the above items, Grau with MMD points out that the customer's tow vehicle needs to meet certain criteria and the compressor needs to be hooked up properly to the tow vehicle.
- Confirm that the tow vehicle is of sufficient size to be able to stop the compressor in an emergency or "hard-brake" situation.
- Confirm that the tow vehicle's hitch is at the correct height so the compressor is towed as close to level as possible.
- Confirm that the safety chains are properly crossed and connected; make sure they're not too long to avoid being damaged by dragging on the road.
- Confirm that the electrical connections are properly matched and made — especially if the compressor has electric brakes.
Important instructions
The type of instructions you give your customers can be the difference between a safe, productive rental and a devastating one. Wagner with Kaeser says a mini-instruction course and safety pamphlet should be given to all customers. "Review all precautions with regular customers, too," he says.
Marc James with Ingersoll Rand says there are several points rental businesses should touch on in order for customers to avoid common compressor danger zones.
"Before disconnecting a hose from the tool or the compressor, make sure all the pressure has been released," he says. "Another pitfall is hose whip, which can occur when a hose is cut or torn. The hose turns into an uncontrolled whip. This can be prevented by using a whip-check cable [also known as break-away protection], such as a short length of cable or chain attached to the tool and hose." (Continued on page 34)
James also notes that operators should be aware of the safety check valve — usually not standard equipment, but an option or aftermarket addition to the compressor. The safety check valve is designed to immediately shut-off the air supply should a break in the hose occur. Having a safety check valve on a compressor is a wise investment for rental yards.
One set of instructions that seems like common sense but needs to be covered, is proper startup and shutdown of the machine, says James. "The proper sequence for startup is connecting the air lines, starting the compressor, then opening the service valves before working," he says. "When you shutdown, you go in the opposite sequence: stop working, close the service valves, turn off the compressor, then clear the lines of pressure. Never shutdown without closing the service valves.
"Also note to customers that the emergency stop should be used just for that — emergencies," he continues. "It shouldn't be used just to turn the machine off, as the compressor could be damaged."
Some more operational dos and don'ts for customers:
- Only use a hose fully rated for the pressure of the machine.
- Protect the hose. The hose can present a tripping hazard so it must be kept out of the way and protected from being damaged — especially from the tools being used.
- Never use a hose that shows signs of damage.
- Never point or direct an air tool at another person.
Final reminders
Don't forget to remind customers about the proper use of personal protection equipment. "Goggles, safety shoes, gloves and hearing protection are a must when operating construction tools," says Wagner. "Other applications may require additional gear."
Grau with MMD adds, "Keep in mind that released compressed air could send loose objects flying, so you will want to make sure your arms, legs and body are protected."
An important note regarding gloves — they should not be worn with any tools that could spin out of control, like an impact wrench.
Because some of your compressor rentals will be long-term, your customers might have to perform some maintenance to keep them running properly. Remind them that first and foremost, their primary responsibility is their safety. "The equipment's well being is secondary," says Wagner with Kaeser. "They should never attempt to repair or troubleshoot a compressor in a manner that could jeopardize health or safety."
Here are some maintenance safety tips for your customers to follow:
- Follow manufacturer's recommendations for proper operation and routine maintenance. Only trained technicians should adjust compressor components.
- Do not adjust safety, blow-off or control valves without referring to the operating manual. For example, improper adjustments can cause "air explosions" from the safety valve — startling and perhaps injuring even experienced operators.
- Do not change filters or check fluids while the compressor is running or pressurized. Spraying fluids such as oil can cause burns or serious injury.
With some informative instructions, common sense and an eye toward safety, your customers can have a safe, productive compressor rental.
author: By Lisa Cleaver, managing editor - Rental Product News