Reducing the Noise with EXAIR Mufflers

Hearing loss is the best known, but not the only, ill effect of harmful noise exposure. It can also cause physical and psychological stress, impair concentration, and contribute to workplace accidents or injuries.

Many manufacturing plants have a strong focus on safety for their workers.  One major safety concern that is overlooked is noise.   The Occupational Safety and Health Administration has a directive, 29 CFR 1910.95a, that defines noise exposure levels over time.  For an eight-hour day, the maximum noise level is 90 dBA.  Hearing loss is irreversible, but it can be prevented.  The CDC, Center for Disease Control, and NIOSH, National Institute for Occupational Safety and Health, report that “approximately 18% of all manufacturing workers have hearing difficulty”1

EXAIR manufactures intelligent compressed air® products to reduce noise levels in the work environment with our Super Air Nozzles, Super Air Knives, and Safety Air Guns for blow-off applications.  But there is another culprit that can be heard; discharge exhaust.  In this blog, I will cover the different types of mufflers that we offer to help reduce these sound levels.

Reclassifying Mufflers are designed to have two functions. They can cut noise levels by 35 dB and remove oil mist from the exhaust air.  Cylinders and valves that exhaust pressurized air may have oil in the line to keep the seals from sticking.  When exhausted, it can create a fine mist, which is dangerous for operators.  Reclassifying mufflers can reduce loud noise while also collecting any contaminants in the exhaust air.

Sintered Bronze Mufflers are simple in design, cost-effective, and easy to install. They have minimal back pressure to not restrict the operations of the pneumatic device.  They come in sizes from #10-32 thread to 1-1/2” NPT.  For a quick and simple way to reduce noise, the Sintered Bronze Mufflers are in stock for fast delivery.

Straight-Through Mufflers offer a way to reduce noise levels without worrying about clogging. They have an aluminum shell lined with sound-absorbing foam, and they can reduce the noise level by 20 dB.  EXAIR offers them with ports of ¼” NPT, 3/8” NPT, and ¾” NPT.  One side has a female thread, while the opposite side will have a male thread.  This can allow you to connect other items like hose kits to reduce noise.

In harsh environments, Heavy Duty Mufflers are used.  They have an outer aluminum shell with an internal stainless-steel screen.  They protect components like valves and cylinders from contamination entering the part.  And, the Heavy Duty Muffler can keep contaminants like rust from being ejected at high speed into the work area. They have a typical noise reduction of 14 dB.

Here is a test for you.  If you go and stand in your plant, you can probably hear loud noises coming from your pneumatic system.  EXAIR has engineered products to solve most of them.  In the Hierarchy of Controls from NIOSH, Personal Protection Equipment, or PPE, is the least effective.  A better control from this chart would be to isolate your operators from the hazard with an engineered product.  EXAIR can offer these solutions for many of your blow-off and pneumatic discharge applications.  If you wish to discuss in further details about the safety improvements that EXAIR can provide, you can contact an Application Engineer.  We will be happy to help. 

John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb

Note 1: https://www.cdc.gov/niosh/topics/ohl/manufacturing.html

Compressed Air Safety

At EXAIR, we have a statement, “Safety is everyone’s responsibility”.  And as a corporation, EXAIR builds our name around this by manufacturing safe and protective compressed air products.  In the United States, we have an organization called Occupational Safety and Health Administration, OSHA, that enforces governmental directives for safe and healthy working environments.  They do training, outreach programs, and educational assistance for manufacturing plants.  They can also enforce these directives with heavy fines for violations.  With compressed air, the two most common violations are air guns and blow-off devices are described in 29CFR 1910.242(b) for dead-end pressure/chip shielding and 29CFR 1910.95(a) for maximum allowable noise exposure.

Here is an example of a nozzle that is dangerous.  As you can see, there is only one opening where the air can pass through from the nozzle.  Other similar types of blow-off devices that would fall into this same group would include copper tube, extensions, and open pipes.

Unsafe Nozzle

They are dangerous as the compressed air cannot escape if it is blocked with your body or skin.  If operated above 30 PSIG (2 bar), these nozzles could penetrate the skin and create an air embolism within the body which can cause bodily harm or death.  This is a hazard which can be avoided by using EXAIR Super Air Nozzles and Safety Air Guns.  The nozzles are designed with fins which allows the air to escape and not be blocked by your skin.  So, you can use the EXAIR Super Air Nozzles safely even above 30 PSIG (2 bar).

Unsafe Air Gun

To counteract the dead-end pressure violation, some nozzle manufacturers create a hole through the side of the nozzle (Reference photo above).  This will allow for the compressed air to escape, but now the issue is noise level.  With an “open” hole in the nozzle, the compressed air is very turbulent and very loud.  The National Institute for Occupational Safety and Health, NIOSH, states that 70% to 80% of all hearing loss within a manufacturing plant is caused by compressed air.  OSHA created a chart to show the maximum allowable noise exposure.  This chart shows the time and noise limits before requiring hearing protection.  The EXAIR Super Air Nozzles, Super Air Knives, Super Air Amplifiers are designed to have laminar flow which is very quiet.  As an example, the model 1210 Safety Air Gun has a sound level of only 74 dBA; well under the noise exposure limit for 8 hours.

Hearing loss is the best known, but not the only, ill effect of harmful noise exposure. It can also cause physical and psychological stress, impair concentration, and contribute to workplace accidents or injuries.

NIOSH created an overview of how to handle hazards in the workplace.  They call it the Hierarchy of Controls to best protect workers from dangers.  The most effective way is by eliminating the hazard or substituting the hazard.  The least effective way is with Personal Protective Equipment, or PPE.  For unsafe compressed air nozzles and guns, the proper way to reduce this hazard is to substitute it with an engineered solution.

One of the last things that companies think about when purchasing compressed air products is safety.  Loud noises and dead-end pressure can be missed or forgotten.  To stop any future fines or purchasing additional personal protective equipment (PPE), it will be less expensive to purchase an EXAIR product.  And with the Hazard Hierarchy of Controls, EXAIR products are that engineered solution.  If you would like to improve the safety in your facility with your current blow-off devices, an Application Engineer at EXAIR can help you.  Remember, safety is everyone’s responsibility. 

John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb

Picture:  Safety First by Succo.  Pixabay License

OSHA Says Keep Compressed Air Use Safe and Quiet: EXAIR Does Just That

The Occupational Safety and Health Act was signed by Richard Nixon in 1970. Under the United Sates Department of Labor, shortly thereafter; OSHA, or the Occupational Safety and Health Administration was born. OSHA is a large regulatory agency tasked to assure safe and healthy working environments by setting and enforcing standards as well as to provide training, outreach and assistance. Although some people’s first response is to cringe at the word OSHA, they have been instrumental in dramatically reducing injury rates and injury costs without negative effects on employees or companies.

Sure we can all cringe by looking up OSHA horror stories on YouTube. And many of us have a story about that one company that was fined 10’s of thousands of dollars for x, y, or z violations… But in reality, OSHA are not the bad guys. They are not looking for fines, in fact they generally give warnings and timelines to fix possible issues, prior to an incident. The fines typically are generated when companies fail to comply. Yes, I know there are always exceptions, but exceptions are not the rule. We hear and hold on to the radical stories, and the day to day, mundane stories fall to the wayside. Regardless of how we feel, we all must comply.

When it comes to EXAIR products, there are two OSHA standards that we must adhere to. One is related to “sound” and one is related to “dead end pressure“.

First let’s look at the dead end pressure. OSHA Safety requirement 29 CFR 1910.242 (b) discusses the possibilities for air embolisms when more than 30 psi is “dead ended” into your skin. EXAIR products have pathways for air to exhaust so that they cannot be “dead ended”. Each product has a way for the air to exhaust to avoid danger. Here are a couple of examples:

Air nozzles have multiple paths to exhaust pressure
Air Knives exhaust the entire path, as well as out each end

Take note that when being used properly (no horseplay) the airflow will have some path to escape and cannot be blocked. They are designed so that air will escape prior to any danger.

Next we will take a look at OSHA requirement 29 CFR-1910.95 (a). This regulation deals with occupational noise exposure. Measuring sound in decibels (dBA) the magic number is 90. Anything under 90 dBA has no limitations on how long you can be exposed to it. For a reference 60 dBA is about the sound level of a normal conversation, or an air conditioner. 70 dBA is about the noise of a washing machine, 80-85 is like city traffic. Then we start getting loud like a motorcycle around 95, shouting or barking is about 110, and standing near a siren is about 120dBA.

Hearing loss is the best known, but not the only, ill effect of harmful noise exposure. It can also cause physical and psychological stress, impair concentration, and contribute to workplace accidents or injuries.

As mentioned, 90 dBA or less is our target to avoid needing alternative solutions such as noise barriers or PPE. Nearly all EXAIR products are compliant at or under 90 dBA. The few exceptions are with some of our high force / extensive reach products such as our High Force Air Nozzles.

Please reach out at anytime if you have any questions, or want to discuss EXAIR and OSHA compliance, or any EXAIR questions at all.

Thank you for stopping by,

Brian Wages

Application Engineer

EXAIR Corporation
Visit us on the Web
Follow me on Twitter

Sound Levels in Your Facility

One of the most common and dangerous hazards that occur within a manufacturing and production facility is the noise level within the plant. Noise is measured in units known as decibels. Decibels are a ratio of the power level of the sound compared to a logarithmic scale. If an employee is an exposed for too long to high levels of noise, they can begin to lose their hearing. That is where the OSHA 29 CFR 1910.95 regulation comes into play.

Hearing loss is the best known, but not the only, ill effect of harmful noise exposure. It can also cause physical and psychological stress, impair concentration, and contribute to workplace accidents or injuries.

This OSHA standard doesn’t just provide the protection against noise in the work place but monitoring as well. Companies shall provide at no cost audiometric tests for all employees to ensure that no damage is being to the hearing of all personnel. This program is to be repeated every six months and the results are to be made accessible to all personnel.                

Hearing is very important to our everyday lives and must be protected due to the fact that once it is damaged hearing loss cannot be lost be repaired. The OHSA 29 CFR 1910.95 is there to protect and monitor this dangerous hazard in the workplace so that all employees can go home safe and sound.

Here at EXAIR we design all of our products to safe and quite. Weather it is using one of our mufflers for vortex tubes or E-vac’s or one of our Super air nozzles we strive to meet and exceed the OSHA standard. One could also purchase EXAIR’s Digital Sound Level Meter which can give a accurate and responsive reading of how loud your compressed air sources are.

For more information on EXAIR’s Digital Sound Level Meter and any of EXAIR‘s Intelligent Compressed Air® Product lines, feel free to contact EXAIR and myself or any of our Application Engineers can help you determine the best solution.

Jordan Shouse
Application Engineer

Send me an Email
Find us on the Web 
Like us on Facebook
Twitter: @EXAIR_JS