6 Important Factors when Choosing a Safety Air Gun

If you look at operating costs alone, compressed air can be just about the most inefficient method there is for cleaning parts. If you just look at the risks, it’s potentially very dangerous too. Don’t even get me started on the insufferable noise it can make.

For cleaning parts, most folks are familiar with the use of an air gun. You can find the simplest of these in many industrial settings: a valve (often in the form of a handheld trigger device) fitted with a nozzle of some sort (often in the form of an open ended tube, pipe, or fitting to focus or direct the air flow). These have all three of the “downsides” I opened this blog with. Of course, these concerns can be mitigated to a high degree by using the right tool for the job. That’s where engineered products like EXAIR Safety Air Guns come in. Let’s look at how we can address these three “downsides”:

Efficiency: This is all about compressed air consumption. In the simplest of air guns mentioned above, consumption is only limited by the passages in the valve (or trigger) and the discharge fitting…and those limits are usually negligible. Modifying the ends (see examples below) to focus the air flow usually has minimal effect, because you’re not appreciably changing the total cross sectional area of the discharge opening:

Here are a few modified thumb trigger air guns that were sent in for Efficiency Lab testing. Left to right, compressed air consumption at 80psig supply pressure was 34.2 SCFM, 30.9 SCFM, and 28.2 SCFM. For comparison (more on this later,) EXAIR Model 1210 Soft Grip Safety Air Gun uses only 14 SCFM and generates a very similar flow pattern.

Safety: Remember learning about kinetic and potential energy in grade school? Well, when you compress air to 100psig, fitting all that air into a much smaller space creates a TREMENDOUS amount of potential energy:

The block on the left represents a cubic foot of air at atmospheric pressure. The one on the right represents how much space the first one takes up when compressed to 100psig. The energy imparted by this process HAS to be handled with care.

One problem with the thumb guns above is, if you were to jam into the palm of your hand and pull the trigger, a large component of that potential energy (pressure) turns into kinetic energy (force)…more than enough to break the skin and cause a potentially fatal condition known as an air embolism. In the United States, OSHA (Occupational Safety and Health Administration) regulates compressed air devices used for cleaning purposes. All EXAIR Safety Air Guns comply with Standard 1910.242(b) by providing a relief path to ensure that it cannot be dead ended, and thus never create over 30psi measurable at the outlet)

EXAIR Super Air Nozzles cannot be dead ended, ensuring the outlet pressure won’t reach OSHA limits, regardless of supply pressure.

Noise: Another problem is, another component is turned into sound pressure…discharging air from a direct opening is quite loud. OSHA standards address these with limitations on outlet pressure and sound level. All EXAIR Safety Air Guns comply with Standard 1910.242(b), which limits the outlet pressure (by providing a relief path to ensure that it cannot be dead ended, and thus never create over 30psi measurable at the outlet) and all but our largest Super Blast Safety Air Guns comply with Standard 1910.95(a) limits for continuous 8 hour sound level exposure.

Which brings us to the topic of this blog: How exactly did THEY (our customer who used to use the thumb guns above) select the right Safety Air Gun, and how can we apply that to getting the right Safety Air Gun for YOU?

These steps aren’t all-inclusive, and they don’t necessarily need to be followed in order, but if you call an EXAIR Application Engineer about selecting a Safety Air Gun, here’s what we’re gonna talk about:

Ergonomics: We offer five distinctive styles of Safety Air Guns:

From small part cleaning by hand, to wide area blowoff, and all points in between, EXAIR has a Safety Air Gun for most any application.

Our thumb gun user (as I alluded to above) chose the Model 1210 Soft Grip Safety Air Guns (top right). They had a number of typical industrial applications where the operators had the parts or surfaces to be blown off right in front of them. They liked the integral storage hook and rubberized hand grip, but the VariBlast Compact (top middle) or Heavy Duty Safety Air Guns (bottom left) were also considered. The VariBlast Precision (top left) and Super Blast Safety Air Guns (bottom right) were too focused or more powerful, respectively, than needed.

Airflow pattern: Honestly, I could make a good case for this being the first consideration. Selection of any blowoff product – be it an Air Nozzle, Air Amplifier, Air Knife, Air Wipe, etc., will largely depend on the size and shape of the airflow.

variety of airflow patterns…and effective distances…are available from EXAIR’s comprehensive line of Super Air Nozzle products.

Application specific concerns: Everything we’ve discussed so far has involved aiming the blow off stream away from the operator, in the direction the device is aimed. In addition to wide variety of engineered Air Nozzles, EXAIR offers a number of options for these products:

Atto Back Blow Nozzles can blow out recesses or holes as small as 1/4″ in diameter.
Scrape off, and blow away, stubborn debris with the Model 1244-48 Soft Grip Super Air Scraper.

If you’re looking for a portable, hand-held compressed air blow off product that’s quiet, safe, and efficient, look no further than EXAIR Corporation’s extensive line of Safety Air Guns. If you’d like to find out more, give me a call.

Russ Bowman, CCASS

Application Engineer
EXAIR Corporation
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Efficiency Lab Leads To Big Savings

EXAIR Corporation manufactures quiet, safe, and efficient compressed air products for industry. We want our customers to get the most out of our products, and, in turn, their compressed air systems. To do that, we offer a unique service called the EXAIR Efficiency Lab. Here’s how it works:

  • An Application Engineer can arrange to have your existing compressed air device(s) sent in to our facility.
  • We’ll use our calibrated test equipment to measure the compressed air consumption, sound level, and force applied of those devices.
  • You’ll receive a detailed test report, along with our recommendations to implement an efficient, quiet, and safety compliant solution.
  • We’ll even send your tested device(s) back to you, at no charge, if you wish.

I recently had the pleasure of conducting just such a test on some air guns.  The caller was the Environmental Health & Safety Director for a plastics manufacturer.  The main concern was safety compliance…a recent audit had shown that some workstations were using handheld blowoff devices that did not comply with OSHA standard 1910.242(b), which limits dead end pressure of compressed air products used for cleaning to 30psi.

After discussing their typical uses for these (and other) air guns, they sent in a couple for testing.  Here’s what we found out:

“Thumb guns” are especially popular for blowoff because of their compact size, ergonomic design. and low price.

The air gun with the 7″ straight extension (top) is a “textbook” example of non-compliance with OSHA standard 1910.242(b).  Because it has an open-end discharge with no relief path, this one could cause an air embolism if it were inadvertently dead-ended into the operator’s skin – a potentially fatal condition.  It also uses a considerable amount of compressed air, and is quite loud.  At 80psig supply pressure:

  • Compressed air consumption is 40.7 SCFM
  • Noise level is 95.5dBA
  • Force applied, at a distance of 12″, is 13oz

For comparison’s sake, EXAIR Model 1210-6 Soft Grip Safety Air Gun is fitted with our Super Air Nozzle, on the end of a 6″ rigid extension:

  • Compressed air consumption is 14 SCFM
  • Sound level is 74dBA
  • Force applied, at a distance of 12″, is 13oz…same as theirs.
Model 1210 Soft Grip Safety Air is fitted with an EXAIR Super Air Nozzle. We can also supply it with a Rigid Extension and Chip Shield (right).

The other one is OSHA compliant (it can’t be dead-ended…the cross-drilled hole provides a relief path, but it was still pretty inefficient and loud.  At our standard test pressure of 80psig:

  • Compressed air consumption is 30.8 SCFM
  • Noise level is 94.8dBA
  • Force applied, at a distance of 12″, is 16.9oz

Although the force generated by the Model 1210 Soft Grip Safety Air Gun isn’t quite as high as theirs, it’s still our recommendation here.  Oftentimes, the flow and velocity generated by the engineered Super Air Nozzle is more than capable of meeting the needs of the typical blow off applications these types of air guns are used in.

EXAIR Efficiency Lab testing proves that replacing these air guns with our Soft Grip Safety Air Guns (or at least replacing the tips with EXAIR Super Air Nozzles…we also have adapters for that) will result in compressed air savings of 66% and 55%, respectively, and lower sound levels to within OSHA standard 1910.95(a) limits:

All EXAIR Soft Grip Safety Air Guns comply with these limits for 8 hour exposure.

If you’d like to know more about the efficiency & safety (or lack thereof) of your current air blow off devices, give me a call.

Russ Bowman, CCASS

Application Engineer
EXAIR Corporation
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Chip Shields, OSHA, And You

Safety is a key part of our culture at EXAIR Corporation.  We have regularly scheduled, all-hands required, safety training on a number of topics.  Our Order Entry team can likely tell you as much about our lockout/tagout procedures as our Machinists can.  Nobody even thinks about entering The Shop without safety glasses, and it’s not just because of the signs.

We pay attention to these…

…so we don’t ever have to use this.

OSHA 1910.242(b) states that “Compressed air shall not be used for cleaning purposes except where reduced to less than 30 p.s.i. and then only with effective chip guarding and personal protective equipment. (emphasis mine)  All EXAIR Intelligent Compressed Air Products are engineered to meet the requirements of the first part (30psi outlet pressure to prevent dead ending…we’ve written about that numerous times, including here, here, and here) and we can also provide pre-installed devices to satisfy the second part:  the EXAIR Chip Shield.

Any EXAIR VariBlast or Heavy Duty Safety Air Gun can come fitted with a Chip Shield, and any Soft Grip Safety Air Gun, except for those with Stay Set Hoses, can as well.  Safety Air Guns with Back Blow Nozzles automatically come with a Chip Shield. The principle is simple: a clear polycarbonate (so you can still see what you’re doing) round disc slips over a short (or long if you want) pipe extension between the gun & the nozzle.  It’s fitted with a rubber grommet so you can position it to where it’s most effective – sometimes that might be closer to the part being blown off; sometimes it may be back a little closer to the operator.

EXAIR Safety Air Guns are available, from stock, with Chip Shields.

If you already have an air gun that’s doing the job, you can easily add an EXAIR Chip Shield to it.  They’re made to fit a wide range of extension diameters, and can even come with the extension if you need it.  We also stock a number of adapter fittings; if you know what threads your air gun has (or if you can send us some photos) we can quickly & easily spec those out for you.

Convenient and inexpensive “thumb guns” with cross drilled nozzles (left) are compliant with the first part of OSHA 1910.242(b). Fitting one with an EXAIR Chip Shield (center) makes it compliant with the second part. A Model 1102 Mini Super Air Nozzle (right) makes it quiet & efficient.

We can provide a Chip Shield for most any device with a threaded fitting. I couldn’t find a way to re-use the non-OSHA-compliant nozzle that came with this gun (thank goodness.)

Another example of a larger air gun fitted with a more powerful cross drill nozzle (left) that can be made totally OSHA compliant with an EXAIR Chip Shield (center.) An EXAIR High Force Super Air Nozzle (right) keeps the power, while reducing noise level and compressed air consumption (right.)

Since 1983, EXAIR Corporation has been manufacturing quiet, safe, and efficient compressed air products for industry (emphasis mine.)  If you have concerns or questions about safety in regard to your compressed air use, call me.

Russ Bowman
Application Engineer
EXAIR Corporation
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Airguns, OSHA, And You

Depending on the context, those may be three words you DON’T want to hear in the same sentence. Case in point…a caller I spoke with recently, who works at a large steel forging plant. During a recent inspection, management was surprised (and disappointed) to find out that, unbeknownst to them, some of their operators had modified some of their compressed air blow off devices.

These modifications left them in violation of both OSHA Standard 1910.242(b) (limit on outlet, or dead end pressure) and 1910.95(a) (limits noise level exposure.)  The OSHA inspector left them with an $8,000.00 fine, and a promise to return with an even higher one if the situation wasn’t corrected.

We discussed the ways their current devices were supplied, the conditions they were operating in, what they were used for…and why the operators had modified them.  Sadly, we found the devices were underperforming due to air supply issues – hoses that were too small in diameter and/or too long, with restrictive quick connect fittings.  And some of their modifications (drilling out the discharge) just exacerbated those problems.

Most of their applications were pretty typical – blowing flash, chips, oil, coolant, etc. from processed metal parts.  Typical enough that a couple of EXAIR Safety Air Guns would allow them to determine what they would need, by taking them around to various stations in the plant and trying them out.

My caller ordered a Model 1210 Soft Grip Safety Air Gun with a Zinc Aluminum Super Air Nozzle (our most popular for typical blow off applications,) and a Model 1260 Soft Grip Safety Air Gun with a High Force 1/2 NPT Zinc Aluminum Super Air Nozzle (the most powerful one available on the Soft Grip Safety Air Gun.)

Here’s Model 1210-6-CS, fitted with a Zinc Aluminum Super Air Nozzle on a 6″ Rigid Extension & Chip Shield.  All EXAIR Safety Air Guns are compliant with OSHA Standard 1910.242(b).

I feel pretty good about the chances of publishing a future blog about the success of this application.  If you want to keep up, I encourage to follow the EXAIR blog – there’s a link to the right to provide your email address – for more on this one, other applications, and a wealth of expert writings on how to get the most out of your compressed air system.

As always, if you’d like to discuss a particular compressed air application and/or product selection, give me a call.

Russ Bowman
Application Engineer
EXAIR Corporation
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