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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Sound: What Is It … More Importantly, Weighted Scales of Frequencies

We’ve blogged about sound and what exactly it is before, see the link. Understanding that sound is vibration traveling through the air which it is utilizing as an elastic medium.  Well, rather than me continue to write this out, I found a great video to share that is written in song to better recap how sound is created.

Now that we have that recap and understand better what sound is let’s dig a little deeper to better understand why some sounds may appear louder to a person when they may not appear different on a sound scale that is shown by something like a Digital Sound Level Meter.

Loudness is how a person perceives sound and this is correlated to the sound pressure of the frequency of the sound in question.  The loudness is broken into three different weighing scales that are internationally standardized. Each of these scales, A, C, and Z apply a weight to different frequency levels.

  1. The most commonly observed scale here in the USA is the A scale. A is the OSHA selected scale for industrial environments and discriminates against low frequencies greatly.
  2. Z is the zero weighting scale to keep all frequencies equal, this scale was introduced in 2003 as the international standard.
  3. C scale does not attenuate these lower frequencies as they are carrying the ability to cause vibrations within structures or buildings and carry their own set of risks.

To further the explanation on the A-weighted scale, the range of frequencies correlates to the common human hearing spectrum which is 20 Hz to 20kHz. This is the range of frequencies that are most harmful to a person’s hearing and thus were adopted by OSHA. The OSHA standard, 29 CFR 191.95(a), that corresponds to noise level exposure permissible can be read about here on our blog as well.

When using a handy tool such as the Digital Sound Level Meter to measure sound levels you will select whether to use the dBA or dBC scale.  This is the decibel reading according to the scale selected. Again, for here in the USA you would want to focus your measurements on the dBA scale. It is suggested to use this tool at a 3′ distance or at the known distance an operator’s ears would be from the noise generation point.

Many of EXAIR’s engineered compressed air products have the ability to decrease sound levels in your plant. If you would like to discuss how to best reduce sound levels being produced within your facility, please contact us.

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF

 

1 – Fun Science: Sound – @charlieissocoollike – https://youtu.be/xH8mT2IQz7Y

 

EXAIR Intelligent Compressed Air Products: Leading the Way in Standards Compliance

EXAIR prides itself in offering products with high-performance and peak efficiency. All EXAIR products are manufactured to meet the strict requirements of a variety of different standards, ensuring that you receive a reliable, high quality product that WILL perform to the specifications we publish.

Safety is a top priority for most companies, EXAIR’s line of Intelligent Compressed Air Products meet or exceed the strict safety standards set forth by both OSHA and the European Union. EXAIR products comply with OSHA 29 CFR 1910.242(b), the standard implemented to ensure safe operation of compressed air blowoff devices, and the EU General Product Safety Directive (2001/95/EC).

sag-osha-compliant
The engineered design of our Super Air Nozzles prevents compressed air from penetrating the skin by eliminating the potential of dead-ending when pressed against the skin.

OSHA Chart

Additionally, they comply with the noise limitation requirements set forth under 29 CFR 1910.95(a) and the EU Machinery Directive (2006/42/EC). From the Optimization product line, EXAIR’s Electronic Flow Control and the Electronic Temperature Control meet the low voltage standards of EU Low Voltage Directive (2006/95/EC). A CE label is placed on all products that comply with applicable directives.

UL

UL, or Underwriters Laboratories, is a third-party safety and consulting organization that certifies products after thorough testing and evaluation. EXAIR’s Cabinet Coolers are UL Listed to US and Canadian safety standards. Static Eliminators are also UL Component Recognized. Within our line of Cabinet Coolers is the Hazardous Location Cabinet Cooler, bearing the Classified UL mark for use in classified areas.

ROHS_Vector

In the assembly of electrical products there can be hazardous materials used during production. The Restriction of Hazardous Substances, also known as RoHS or (2002/95/EC), restricts the use of materials such as: lead (Pb), mercury (Hg), cadmium (Cd), hexavalent chromium (CrVI), polybrominated biphenyls (PBB), polybrominated diphenyl ethers (PBDE), and four different phthalates. The electrical portions of EXAIR’s Static Eliminators, Electronic Flow Control, Electronic Temperature Control, Digital Flowmeter, solenoid valves, and thermostats all comply with the amendment outlined in the European Commission decision L 214/65.

In addition to RoHS, EXAIR is also committed to providing products that are conflict mineral free. In support ofconflictfree_v2 Section 1502 of the Dodd-Frank Wall Street Reform and Consumer protection Act, EXAIR complies with the conflict minerals rule to curb illicit trade of tin, tantalum, tungsten and gold in the DRC region. Using the CMRT 4.20 template, we’re able to document our supply chain to ensure our materials are not being sourced from places that could finance conflict in the DRC and surrounding countries.

reachFinally, per Regulation (EC) No 1907/2006 Title I, Article 3, paragraph 3, the European Union enacted legislation requiring substances and chemicals imported into the EU to be registered to ensure a high level of protection for human health and the environment. Per Title II, Article 7, paragraph 1, articles must be registered when a substance is intended to be released during normal conditions of use that would exceed 1 metric ton per producer per year. Since EXAIR products do not contain substances that are intentionally released, registration is not required.

If you’re looking to maintain compliance in your industry, EXAIR products have you covered. If you have any questions about these standards of compliance feel free to reach out to us. Our team of Application Engineers have years of experience in industry are waiting to take your call.

Tyler Daniel
Application Engineer
E-mail: TylerDaniel@EXAIR.com
Twitter: @EXAIR_TD