How to Meet the OSHA Compressed Air Standard

Every day we talk to customers who need to comply with OSHA regulations for using compressed air to clean up their shop or product. Back in 1972 on Valentine’s Day, OSHA published Directive Number STD01-13-001 standard 1910.242(b), which strives to provide guidance on how manufacturers can safely use compressed air for cleaning purposes to comply with the Walsh-Healey Act of 1936.  This directive laid out acceptable methods for complying with 41CFR 50-204.8 and 29 CFR 1910.242(b)

The two methods are very simple, but still many people have questions.  The first method (pictured below) is to regulate the line pressure from the compressor to below 30 PSIG.

Regulator Method

Figure 1 Regulator method Photo Courtesy of osha.gov

The second method is to install a nozzle engineered to reduce the static pressure of the nozzle to less than 30 PSIG.

OSHA Nozzle Method

Figure 2 Nozzle method Photo Courtesy of osha.gov

The first method reduces the danger by limiting the energy in the system to less than an amount which can injure a person.  OSHA determined that 30 PSIG was the safe limit for the amount of pressure the human body could withstand without causing severe injury. The problem with this method is that cleaning with compressed air at 30 psig is virtually impossible.  Which means at such a low pressure the operator must pass the nozzle so close to the chips and debris, he might as well use a broom or pick each piece of debris up with his fingers. This first method I will label the regulator method. The second method introduces a relief valve at the nozzle, so that an operator cannot block off all of the openings of the nozzle, and build up any static pressure on their skin. I will call this the nozzle method.

Commonly and cheaply, the nozzle method is done by cross drilling a hole in an open pipe.  This is a sometimes effective method for protecting employees from static pressure, but it also is great at producing a tremendous amount of noise and wasting a lot of compressed air every year. The noise produced by even a ¼ pipe with a cross drilled hole fed with 80 PSIG can easily exceed 90 dBA and consume up to 140 SCFM. The noise can be even louder, if there are burrs or rough edges from drilling out the pipe.  This is also a violation of OSHA standard 29 CFR – 1910.95 (a), if the employee is not using hearing protection.

Air Nozzle work

To meet this OSHA standard, EXAIR’s solution is to engineer features which cannot be dead-ended into a wide variety of compressed air products. We do this a variety of ways depending on the product.  For the Super Air Nozzles, we utilize multiple small orifices which are protected by raised fins.  The multiple orifices offer an escape path for the air in case a single orifice is plugged. The fins protect the orifices so that no one person can block more than one orifice at a time.

So if you are worried about an OSHA inspector knocking on your door, or maybe you aren’t sure if you should be worried, contact us.  The Application Engineering team here will help you determine what engineered solution you need to keep those pesky fines away.

Dave Woerner
Application Engineer
Davewoerner@EXAIR.com
@EXAIR_DW

The Professor’s Assistant Has Come a Long Way

Today, I’m writing one of my last regular blogs for EXAIR. Since the Professor has moved on to his higher calling, I have started working for EXAIR as a design engineer. In 2008 I was a design engineering co-op student for EXAIR. I didn’t know anything about air. I had to learn the difference between CFM (cubic feet per minute), SCFM (standard cubic feet per minute) and ACFM (actual cubic feet per minute). I had to learn that a 1/4 pipe does not measure 1/4″ anyway you measure. I found out the hard way to point the 1116 Super Air Nozzle toward the ground, because it will lift ceiling tiles in short order. EXAIR stuck with me as a co-op to allow me time to grow and learn. At the same time EXAIR continued to grow and expand as well. Once my co-op turns were over, I left EXAIR at the end of 2009. I finished my degree and got some experience outside the company. In 2013, I rejoined EXAIR as an Application Engineer.

I have been writing entries for the EXAIR blog for two years. Looking back through my most viewed posts, I see topics on Air Knivescomplying with OSHA, and Videos. I also see an accomplishment, Product of the Year Award Winner. Third on the list though is On the Job Training: Internships and Co-ops. I wrote this blog with “The Professor” in mind…

I had just learned that he was leaving EXAIR and it made me pause for a time to think about “The Professor”. He was the driving force behind the Co-op program here at EXAIR. In doing so he was sticking his neck out. I’m sure first on his mind was getting someone who could do his dirty work. No one wants to test Line Vacs in the summer. It is hot and messy work. “The Professor” wasn’t above getting dirty, but I think he wanted to be.

But in hiring a Co-op, he wasn’t just making his life easier. Everyone will attest I had a lot to learn. In the first year of working with “The Professor”, he spent as much time training me as I spent producing useable material. I like to think he ultimately got more out of me than he put it in, but training Co-ops is quite an investment in time.

In moving over to design engineering, I feel much more confident that I will be able to teach our new Co-ops a good way of doing their work. It is such a leg a up to have spent time in their shoes. “The Professor” ultimately never got to benefit from me working for him as a engineer. The work he put in training several Co-ops has been an excellent investment in the future, and I hope more companies follow his example.

Dave Woerner
Design Engineer/Application Engineer/Co-op
DaveWoerner@EXAIR.com

 

EXAIR Air Wipes Offer an Improvement Over Competition

Last week, I had a customer using a competitor’s air wipes to remove water from an extrusion. These were air wipes built from UHMW blocks or similar material with a hinge and some air holes drilled in it.  He had several extrusion lines, and on each of these lines he used several air wipes. The one positive of these air wipes is they used less air than EXAIR’s Air Wipes, so on paper they seem the better choice. In practice it took 5 of these Air Wipes to do the job of one EXAIR Super Air Wipe. In addition to being more effective, EXAIR Air Wipes were also less expensive and produced a lower noise level.

The customer had two sizes of air wipes. The smaller version was a 1/2″ Air Wipe which used 8.3 SCFM (times 2 = 16.6 SCFM) at 80 PSIG, but it produced a noise level of 85 dBA. EXAIR Super Air Wipe, model number 2400, requires 13.9 SCFM and produces a quiet noise level of 75 dBA at 80 PSIG inlet pressure. EXAIR’s air wipe is able to easily remove water from an extrusion in a single pass. The 360 degree uniform blast of air works to remove water evenly and quickly. We offer the Air Wipes in aluminum and stainless steel with a braided stainless steel air line to join the two halves of a clamshell design.  The EXAIR 1/2 Air Wipe produced a much better blow off while reducing noise level by 10 dBA.

Super Air Wipe

1/2″ Super Air Wipe

The larger version of the air wipe was a 2″ unit that used 15.3 SCFM (times 3 = 45.9 SCFM) of compressed air and created 80 dBA of noise at 80 PSIG of inlet pressure. The EXAIR 2″ Super Air Wipe, model 2402, used 29.5 SCFM and lowered the sound level to 77 dBA at 80 PSIG of inlet pressure.  The EXAIR Super Air Wipes also were significantly thinner than the competitive offering which allows them to fit in tighter spaces. The EXAIR 2″ Air Wipe is 1.125″ in depth, the competitor’s product was more than 4″ long. By reducing the amount of the space need on the line and reducing the number of Air Wipes needed EXAIR was able to supply a better Air Wipe for their extrusion process.

 

EXAIR 2" Super Air Wipe

EXAIR 2″ Super Air Wipe

Dave Woerner
Application Engineer
@EXAIR_DW
DaveWoerner@EXAIR.com

When Two Arms Aren’t Enough

This morning I was chatting with my colleague Russ Bowman about taking care of kids. I was complaining about having to try and chop vegetables while holding a 1 year old in my other arm. Russ shared some perspective with me. He always took pride in what he could get done with an infant or toddler in one arm. While I was complaining, he pushed me to see what I could really get done. I thought cutting squash was pushing it. He informed me that I lack either imagination or perseverance in my dad skills. I wish his wife (or mine) had been around because, I’m pretty sure they would offer “perspective” to both of us about how much you can get done with infant in your arms. Which would be fine, Russ and I know our better halves are better than us… Thank Goodness. Otherwise, the kids would not stand a chance.
The discussion reminded me of EXAIR’s foot pedal. It is like an extra hand to control your air supply. I had a customer this week that was punching 4 mm diameter plastic circles from a part. The 4 mm diameter plastic chips built up on the machine which would lead to a housekeeping nightmare. The customer installed a 3/8″ Line Vac, model 6078, to evacuate the plastic chips after each punch. The Line Vac worked great to evacuate the chips, but running it constantly required 5.6 SCFM of compressed air. To get the job done, the Line Vac only needed to run five seconds after each punch operation, and the punch operated three times every minute. Controlling the air supply to the Line Vac to only turn on when the Line Vac was needed would save 4.2 SCFM of compressed air.

line vac drill press

Picture Model 6080 Line Vac removing chips from a drill press.

Unfortunately, the operation required two hands. One hand to position the plastic blank, one hand to actuate the punch. This meant controlling the Line Vac would need a third hand. With a foot pedal, model number 9040, though, the operator could gain additional control to operate the Line Vac only when needed. This saved 4.2 SCFM of compressed air. The foot pedal would pay for itself in 124 days. On a 3/8″ Line Vac that may not seem like much, but a foot pedal controlling a 2″ Line Vac would save 33.75 SCFM and the payback time would be 15 days.*

*Assuming 24 hour day and 250 working days per year.

A foot pedal is an excellent option, when you need that third arm. Check one out today at www.exair.com.

Dave Woerner
Application Engineer
@EXAIR_DW
DaveWoerner@EXAIR.com

 

Intelligent Compressed Air Products: Pulling In Free Air

Home of Intelligent Compressed Air Products

EXAIR is the home of Intelligent Compressed Air Products.

What is an Intelligent Compressed Air product? What makes it intelligent? Compressed air is typically a manufacturing facility’s most expensive utility. A standard cost is $0.25 per 1,000 Standard Cubic Feet (SCF) produced. Any pipe, manifold, or fitting can be modified to blow compressed air, but these homemade blow offs will be very noisy, waste a tremendous amount of compressed air and create an OSHA violation. In contrast EXAIR’s intelligent compressed air are engineered solution are quiet, use a minimal amount of compressed air and comply with OSHA safety standards.

Let’s take EXAIR Model 1100 Super Air Nozzle as an example. Connecting it to a 1/4 NPT fitting, will produce 13 ounces of force on a target when mounted twelve inches away, and use 14 SCFM of compressed air. To produce so much force using that little air, the Super Air Nozzle must be precisely designed and manufactured to maximize the entrainment of ambient air.

With the air nozzle we use compressed air to induce a primary air flow. This primary air flow is a high velocity jet of air that create low pressure area around the primary airflow entraining the ambient or free air. These air streams combine past the tip of the nozzle creating a powerful blast of air. The Super Air Nozzle can entrain air up to a ratio of 25 parts of ambient air moved for every 1 part of compressed air.  All of our Super Air Nozzle create this level of air entrainment.

AirflowAnimation

EXAIR Super Air Nozzle entrains ambient air up to a 25:1 ratio

In addition to entraining a significant amount of air, the Super Air Nozzle also reduces the noise level. Most homemade nozzles are not well constructed so, the hole(s) that allow the air to escape may have sharp jagged edge which will induce noise or turbulence. Even commercial nozzles with cross drill holes create a tremendous amount of wind shear which leads to an ear splitting compressed air squeal. The smooth design of the Super Air Nozzle creates a laminar flow of air that reduces the noise of the nozzle to 74 dBA. For reference a 1/4″ open tube can easily create noise levels over 100 dBA. Using a compressed air nozzle, can greatly reduce the amount of noise in and around your shop.

Finally, EXAIR Super Air Nozzle complies with OSHA standard 29 CFR 1910.242, which requires that all nozzles that use compressed air over 30 PSIG must provide a point of relief in case the nozzle is dead ended. EXAIR Super Air Nozzle uses multiple orifices that are recessed, so that the air always has a path of escape. Many homemade nozzles do not have any provision to protect from dead ending, which means they do not comply with the OSHA standard.

EXAIR Super Air Nozzles are an important upgrade from a homemade nozzle and many times an upgrade for a commercial nozzle, because they entrain ambient air, reduce noise level, and comply with OSHA regulation.

Dave Woerner
Application Engineer
@EXAIR_DW
DaveWoerner@EXAIR.com

EXAIR Webinar: Simple Steps for Big Savings

EXAIRvOpenpipe_200psqRed

EXAIR Super Air Nozzle Versus and Open Blow off

EXAIR will present a free webinar hosted by Design World September 15th, 2015 at 2 pm EDT ( UTC/GMT -4 hours). I will be presenting the webinar about Intelligent Compressed Air Products. What do we mean by Intelligent Products? We are referencing nozzles that are quiet, safe, and efficient. They are engineered and manufactured to improve efficiency and limit compressed air use by entraining ambient air. The smooth lines of these nozzles produce laminar flow that reduces wind shear creating a powerful quiet blow off.

The focus of the webinar will be to quantify the cost of homemade blow offs and the return on investment of upgrading these simple installations to an engineered solution. We will base our calculations on a 20 HP Air Compressor, an 1100 Super Air Nozzle, a 1/4 Open Copper tube, and $0.08 per kWH electricity cost.

In addition to the cost of compressed air, we will cover two safety issues. First, we will cover dead end pressure. OSHA standard 29 CFR 1910.242(b) limits the dead end pressure to less than 30 PSIG. We will talk about what type of nozzles do not comply with this regulation, and how engineered nozzles are designed to meet this requirement. Second, we will talk about the noise exposure standard and the effects noise will have on your facility.

The main focus of the presentation will be cost of compressed air blow offs, noise, and important OSHA standards for compressed air. We will also touch on a variety of other compressed air topics. The presentation will be sponsored by EXAIR with 31 years of end-use compressed air product manufacturing and application experience.

CLICK TO REGISTER HERE

Dave Woerner
Application Engineer
@EXAIR_DW
DaveWoerner@EXAIR.com

Wood Veneer Pressing Using Venturi Technology

We get some odd calls at EXAIR. Selling factory direct to the end-user means we field calls from all types of people. One these calls turned into a unique and great application.

An amateur woodworker called in looking for a vacuum pump or vacuum generator in order to glue up wooden veneers into complex shapes. This was an application I had not yet assisted anyone with and needed further investigation to understand the process. I found the video below showing the basic mechanisms for the vacuum bag pressing of wooden veneers.

EXAIR vacuum generators, or E-Vacs, are perfect for this application. The E-Vacs, are compressed air powered venturis that  provide vacuum up to 27″ of mercury. In this application once the vacuum is pulled a there is no air flow, so a non-porous vacuum generator is perfect. The customer was able to use our 810002 2 SCFM non-porous vacuum generator, a vacuum switch, and a solenoid to create a flexible veneer press in his own shop. I was immediately struck by how effective this method would be. It is commonly used in for flat pieces, but I could see it being used to form convex curves for artistic pieces.

Here is a time lapse video of a similar process which also features a (helpful?) dog. There are not as many details in this video but it does show some steps not shown in the above video. Plus, it has a dog, and I like dogs.

If you have any questions or would like to discuss an application, please contact EXAIR.

Dave Woerner
Application Engineer
1-800-903-9247  OR  513-671-3322 outside of USA and Canada
@EXAIR_DW
DaveWoerner@EXAIR.com

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