Is It Safe To Use Compressed Air?

Think about it…compressed air is, by definition, gas under pressure: potential (stored) energy.  This energy is intended to do work, like operation of pneumatic tools, actuation of pneumatic cylinders, debris removal with an air gun or blow off device, and (even though I haven’t done it in a while) my personal favorite:

High pressure compressed air is meticulously made, prepared, and stored to ensure the number of surfaces equals the number of dives.

Uncontrolled, unplanned, or accidental releases of stored energy (regardless of the source) are inherently dangerous, and great care must be taken to guard against such incidents.  This is accomplished, primarily, in three areas:

*Operation.  This might be the most prevalent, because it involves the greatest number of personnel (e.g., everyone) as well as the ways compressed air is used (e.g., all of them.)  It’s also the area where the most involved people (the operators) have the most control:

  • Personal protection.  Don’t even think about operating a compressed air device without eye protection.  Ever.  Hard stop.  Also, if the operation involves flying debris, a full face shield, long sleeves, gloves, etc. might be called for.  Hearing protection may be required as well…keep in mind, even if an engineered device (like any of EXAIR’s Intelligent Compressed Air Products) generates a relatively low sound level, the impingement noise of the air flow hitting the object can reach dangerous levels.
  •  Personnel cleaning is prohibited.  The risk of injury to the eyes, respiratory system, and other parts is just too great to rely on personal protective equipment that’s designed for use while discharging compressed air AWAY from the body.  While this is expressly prohibited in certain situations, OSHA has long recognized it as good practice for all industries.
  • No horseplay.  ’nuff said.  Plenty of better ways to have fun at work.

*Design.  This one usually has the advantage of being traceable to a small number of people, and is also the one that’s most likely to be documented.  This is where it starts…if the system is designed to fail, it doesn’t matter how much care the operators take:

  • Supply lines, fittings, and hoses must be rated for use with compressed air, up to and exceeding the maximum discharge pressure of the air compressor.
  • This goes for any tools, blow off devices, components, etc., serviced by the air system.  The only thing worse than a component failing is a component failing in your hand.
  • Shut off valves should be located as close as practical to point(s) of operation.  This allows you to quickly secure the flow of compressed air to a failed component, hose, etc., and prevent further damage or risk of injury.
  • Hoses shouldn’t be run across the floor, where they can become a trip hazard or subject to damage from stepping on them.   This is a surefire way to find out the value of shut off valves (see above.)

*Product specification.  Or, more simply put, using the right tool for the job.  A broader discussion could include efficiency and performance, but we’ll stay within the confines of safety for the purposes of this blog:

  • Be mindful of dead end pressure.  Blow off devices, especially hand held ones like air guns, are oftentimes fitted with a simple open-end discharge.  If this is pushed into a part of the body, the pressurized air can break the skin and cause an air embolism.  This is a serious injury, and can be fatal if it reaches the heart, lungs, or brain.
    • This is a key consideration to OSHA Standard 1910.242(b), which limits the downstream pressure when compressed air is used for cleaning to 30psi.
    • EXAIR products are compliant with this Standard by design…there’s always a relief path for the air pressure; they can’t be dead ended.
Because the compressed air exits through a series of holes, recessed between a ring of fins, any attempt to block the air flow will simply send it in another direction.
  • Harmful sound levels are a consideration as well.  As stated above, hearing protection is required in many cases, but sound levels can be mitigated through the use of engineered products.  EXAIR Intelligent Compressed Air Products, as a result of their high entrainment, generate a boundary layer of air flow that leads to dramatically lower sound levels than a similar-sized open end blow off device.

If you’d like to explore ways to make your compressed air system safer, give me a call.

Russ Bowman
Application Engineer
EXAIR Corporation
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Better Understand Your Blowoff Process with EXAIR’s FREE Efficiency Lab

panoramic view
The EXAIR Efficiency Lab

Many customers may not have the means to test the air consumption of their blowoff solutions. With compressed air being the most expensive utility in a manufacturing facility, it’s important to identify places where you can save money on your overall operating costs. EXAIR manufacturers a wide variety of products intended to help you reduce your compressed air usage. If you’re not able to accurately measure the consumption in your own shop, we invite you to send the products into EXAIR for testing. With EXAIR’s Award Winning Efficiency Lab, just simply contact an Application Engineer, box them up and send them to our warehouse in Cincinnati, Ohio.

EXAIR Efficiency Lab

Once we receive it, our engineers will complete some in-depth testing to determine the compressed air consumption, sound level, and force that your current solution provides. With this information, we’ll be able to compare it to an EXAIR Engineered Solution. This way we ensure that you receive the best, safest solution possible also capable of saving money through reduced air consumption and improved efficiency.  We’ll send you back a comprehensive report that’ll help you to make the best decision for your company.

I’ve been recently working with a customer that sent in one of the nozzles they’re using across all their CNC machines. They wanted us to test it out and see if we’re able to offer them something that could reduce their overall compressed air usage. The nozzle was one of the cheap plastic varieties and was attached to a commonly used modular hose. This type of modular hose is not designed for operating under high pressures. These hoses are more suitable for liquid coolant or air that is at or below atmospheric pressure.

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Inefficient and unsafe plastic nozzle

After testing, we found that at 80 psig the nozzle consumed 3.85 SCFM and produced a force of 1.92 oz. We also noticed that after 60 psig, the nozzle began to leak due to a poor seal where the nozzle met the brass hex. The EXAIR nozzle most suitable to replace this was the 1108SS. At just 2.5 SCFM at 80 psig, replacing the plastic nozzle with an engineered solution saves them 35% of their overall consumption for this blowoff. With close to 1000 of these nozzles in operation, that adds up quickly!!

In addition to increasing efficiency, replacing these nozzles also greatly increases overall worker safety. The sound level is reduced from 73 dBA to just 58 dBA and EXAIR’s nozzles also adhere to OSHA 1910.242(b). The plastic nozzles could be dead-ended, posing a hazard that can result in costly fines. These fines are assessed per infraction, so having multiple non-compliant nozzles can easily get very expensive if you’re subject to an unannounced visit by an OSHA inspector.

If you think you may have an opportunity to improve upon your existing blowoff methods, give us a call. We’ll be happy to take a closer look and have you send the product back to EXAIR for a quick trial in our Efficiency Lab. You’ll be glad you did!

Tyler Daniel
Application Engineer
E-mal: TylerDaniel@exair.com
Twitter: @EXAIR_TD