Tag: embolism

Compressed Air Safety Dos and Don’ts

Published on by Russ BowmanLeave a comment

In the Navy, it was a universally accepted fact that NOTHING onboard the ship was “sailorproof.” Regardless of how it was designed, what it was made of, how many interlocks, mechanical stops, automatic shutoffs, etc., something had, any & all of those features could be overridden (by accident or on purpose) and cause a wide range of chaos, and/or damage, and/or injury. That’s why training and procedures are so important.

It’s the same in any civilian/corporate industry too – any device, tool, instrument, machinery, etc., can be inherently dangerous if it’s not used properly. And “used properly” for a LOT of those includes personal protective equipment, commonly known as PPE.

In the United States, the Occupational Safety & Health Administration (OSHA) publishes a couple of standards relevant to the safe use of compressed air:

Standard 1910.242(b) applies to the use of compressed air for cleaning. It states “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.”

  • Do wear eye protection, at a bare minimum, in regard to the personal protective equipment, no matter what. If the debris you’re blowing off is sharp or jagged, a full face shield & long sleeves are likely called for as well.
  • Don’t operate a blowoff device in a manner where the static pressure at the outlet of the nozzle will reach or exceed 30 p.s.i. If you’re using an engineered product like an EXAIR Super Air Nozzle, it’s perfectly fine to use a higher air supply pressure than that. They’re designed so that the outlet pressure won’t exceed 30 p.s.i. no matter what the supply pressure is.
EXAIR engineered Air Nozzles, like the Model 1100 Zinc Aluminum Super Air Nozzle shown here, discharge the compressed air flow through a series of holes, recessed between an array of fins. This means that there’s always a relief path for the airflow, so the outlet pressure cannot reach a dangerous level.

Standard 1910.95(a) isn’t exclusive to the use of compressed air, but since the discharge of a high pressure gas to atmospheric pressure can create quite a racket, noise levels associated with the use of compressed air often exceed exposure limits published in this standard.

  • Do protect your ears, same as you do your eyes. This one is near & dear to me, because my Dad lost a significant amount of his hearing in his early 40’s as a result of occupational noise exposure, and I saw first-hand what an impact that has on quality of life…for him, and frankly, for us too. There are a number of ways to do this, and the National Institute of Safety & Health (NIOSH) ranks them in order of effectiveness in their Hierarchy of Controls.
  • Don’t make earplugs, earmuffs, headphones, etc., the first and only line of defense. Don’t get me wrong; they work GREAT when the right ones are used properly…”right” and “properly” being the key words there.
  • So, DO make selection, training, and enforcement of their usage a high priority if the source of the noise cannot be:
    • Eliminated – this can be a toughie, because whatever’s making the noise is very likely there for a reason.
    • Substituted – this is a much more common, and still highly effective method, as engineered products like EXAIR manufactures can dramatically lower noise levels while maintaining the effectiveness of compressed air usage.
Examples of some sound levels we’re all familiar with, and how some EXAIR products compare favorably.

In closing, my last dos & don’ts are: Do heed OSHA’s safety standards, so you don’t get a hefty fine for endangering yourself or the folks you work with. Frankly, if they catch you before anyone gets hurt, you got off light. If you’d like to find out more about how EXAIR Intelligent Compressed Air Products can improve safety with your compressed air usage, give me a call.

Russ Bowman, CCASS

Application Engineer
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What OSHA 1910.242(b) Means For Compressed Air Product Users

Published on by Russ BowmanLeave a comment

Medically speaking, our skin is an organ…and an amazing one at that. It protects our internals from an incredibly harsh environment as we’re bombarded by radiation (sunlight), subjected to summer’s heat & the cold of winter, attacked by fierce invaders (from viruses & bacteria to insects & spiders), all while we carry on at the bottom of a 60 mile-deep ocean (of air!)

Our skin requires some protection too: Sunscreen mitigates some of the harmful effects of solar radiation, shoes protect our feet from the ground, gloves & coats prevent frostbite, and compliance with OSHA Standard 1910.242(b) protects operators who use compressed air devices for cleaning purposes from air embolisms. That’s when air, under pressure, has enough energy to break the skin (tough as it is) and reach the tissue underneath. It’s painful, and serious enough that the victim should absolutely seek emergency medical treatment. If the air breaks a blood vessel and enters the pulmonary system, it can be deadly, in a hurry.

In 1971, the U.S. Occupational Health and Safety Administration (OSHA) determined that air under pressure higher than 30 pounds per square inch is capable of causing such injuries, if the pressurized source is dead-ended into the skin. Based on this determination, they included the following verbiage in Standard 1910.242, regulating the safe operation of hand and portable powered tools & equipment:

1910.242(b) Compressed air used for cleaning. 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.

In February 1972, OSHA issued Instruction STD 01-13-001 to clarify the meaning of 1910.242(b), with two illustrations of acceptable methods to meet compliance. The first is the use of a pressure reducer (or regulator):

While this method is compliant with the OSHA Standard, it’s kind of impractical, since you’re not going to get a whole lot of cleaning done with such a low energy air flow. If that’s not bad enough, it’s STILL going to be loud, and wasteful as far as the cost of compressed air goes.

The other method illustrated in the Instruction’s enclosures involves the nozzles themselves:

Compressed air product manufacturers use this method to make OSHA compliant Nozzles.

One design that complies with OSHA 1910.242(b) using this method is the cross drilled nozzle:

Unless it’s blocked off, practically all of the air flow goes straight out the end, but if you block off the end, it all goes out the cross drilled hole. As long that hole is properly sized, you won’t build up 30 psi at the main outlet.

If you’re not concerned about high operating cost or deafening noise, you can stop reading now; these are all you need for OSHA compliance with Standard 1910.242(b). If you DO care about spending less money on compressed air or complying with OSHA Standard 1910.95(a) (which you read all about here), let’s spend a minute on engineered compressed air nozzles:

EXAIR Super Air Nozzles discharge compressed air through an annular array of holes, recessed between a series of fins. This causes the primary (compressed air) stream to entrain an enormous amount of air from the surrounding environment.

In addition to making them cost less to operate (since most of the total developed air flow is entrained), they’re also VERY quiet (since the entrained air forms a boundary layer on the outside of the air stream), AND they can’t be dead ended:

Since the fins won’t allow for a complete blockage of the compressed air discharging from the Super Air Nozzle, this design is a prime example of a built-in “relief device” as defined by Instruction STD 01-13-001, above.

All EXAIR Intelligent Compressed Air Products, in fact, incorporate a form of built-in “relief device”:

The overhang of the cap on the Flat Super Air Nozzles and the Super Air Knives prevent them from being dead ended.

If you’d like to discuss safe use of compressed air, it’s one of our primary goals here at EXAIR – give me a call.

Russ Bowman, CCASS

Application Engineer
EXAIR LLC
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About OSHA 29 CFR 1910.242(b) for Compressed Air Safety

Published on by Brian FarnoLeave a comment

In February of 1972 OSHA released a standard to improve worker safety when operating handheld compressed air devices being used for cleaning purposes. This directive focuses around human skins permeability. That is, if you were to take an open ended pipe that had compressed air being discharged over 30 psig it can actually push through the skin and create an air embolism.

OSHA’s Directive 29 CFR 1910.242(b)

Air Embolisms are extremely painful, and in extreme cases, can be deadly. The risk associated with an air embolism can be mitigated by following the OSHA directive and reducing the downstream pressure of an air nozzle or nozzle pressure below 30 psi for all static conditions. Dead ending is when the passageway for the air becomes blocked and turns a dynamic flow of air into a static flow. This is in the event the pipe, nozzle, lance, etc. becomes blocked by a human’s body. This is a directive that all Intelligent Compressed Air® products from EXAIR focus on meeting or exceeding.

Our Air Nozzles and Jets video shows a great depiction of how this can be achieved with our engineered design of nozzles. The recessed holes and the fact that there are multiple passages for the air to exit are easy to see on the nozzle. Products like the Super Air Knife may not be so easy to see but the way the air knife cap overlaps prevents the Super Air Knife from being dead ended in the event an operator comes into contact with the discharge air.

Even though this directive was created in 1972 it continues to be at the forefront of industrial environments. I have even been to a custom artwork facility that was effected by this standard because they would use a handheld blowgun to remove dust and debris before matting and framing artwork with glass. They also removed dirt and dust from the frames before paint. This wasn’t your typical manufacturing environment yet they were still held to the same standards and were made safe by implementing engineered solutions such as our Super Air Nozzle.

If you would like to discuss how we can help increase your operator safety and ensure you meet or exceed OSHA 29 CFR 1910.242(b), please contact an Application Engineer today.

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF

1 – OSHA Instruction STD 01-13-001 – Retrieved from: https://www.osha.gov/enforcement/directives/std-01-13-001

Increase Safety and Gain OSHA Compliance By Using An Engineered Solution

Published on by exaircorpLeave a comment

In 1972, the US Department of Labor’s Occupation Safety & Health Administration (OSHA) established Standard 29 CFR 1910.242(b) to reduce the outlet pressure to less than 30 psi, of an open pipe, nozzle, air gun, etc. when being used for cleaning. The intent of this directive was to prevent injury to operators. They determined that 30 psi was the pressure in which the skin could be broken if the device were dead-ended against the operator’s body, causing an injury known as an air embolism…the dead-ended force of the air, under pressure, breaks the skin and introduces air flow inside the body. This is a VERY dangerous condition which can quickly lead to serious injury, possible stroke or ultimately death.

While OSHA doesn’t recommend any type or manufacturer of device, they do provide two methods you can follow to gain compliance.

The first would be to reduce the operating pressure below 30 PSI, as shown in the below line drawing.  This, of course, limits the strength and usefulness of the exhausting air flow before it reaches the nozzle and before it is used upon the application.

 

The other method indicates using a nozzle which includes a pressure reducer or a relief device which will reduce the air pressure to less than 30 psi if the nozzle is dead ended. All of EXAIR‘s products are engineered to meet or exceed this Standard. In the case of our Super Air Nozzles, the air exits through a series of jets, recessed behind an array of fins, so the outlet holes cannot be blocked directly, any potential obstruction of the outlet air holes results in the air having an alternative route to avoid injury to operators and personnel. This allows the full pressure (the highest energy) to reach the nozzle and the application. 

Open air lines and homemade blow offs violate OSHA standard 1910.242(b) because of harmful dead end pressures. If you would like to discuss how EXAIR products can help you gain OSHA compliance to increase personnel safety and avoid costly fines, please give me a call, I’d be happy to help.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

Line drawings used from OSHA’s website