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

OSHA and Compressed Air Safety; Things to Review.

EXAIR Super Air Nozzles are fully OSHA Compliant – our Compliance Certificate is available upon request (left.) Your power strip and Christmas tree lights should have labels showing their current ratings – check these so you don’t overload the circuit (right.)

At EXAIR, we have a statement that says, “Safety is everyone’s responsibility.”  As a corporation, EXAIR builds its name around this by manufacturing safe and protective compressed air products.  In the United States, we have an organization called the 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 to reduce injuries and fatalities.  They can also enforce these directives with heavy fines for violations.  With the compressed air system, the two most common violations are 29CFR 1910.242(b) for dead-end pressure/chip shielding and 29CFR 1910.95(a) for maximum allowable noise exposure.

Unsafe Nozzle

Above is an example of a nozzle that is dangerous.  As you can see, there is only one path where the air can pass through and this path could be blocked.  Other similar types of blow-off devices that would fall into this same group would include copper tubes, flexible lines, and open pipes.  They are dangerous as the compressed air cannot escape if it is blocked by your body or skin.  If operated above 30 PSIG (2 bar), the air from 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 allow the air to escape and prevent blockage of the airflow.  So, you can use the EXAIR Super Air Nozzles safely above 30 PSIG (2 bar) and remain OSHA safe.

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 CDC reports that in 2007, “82% of the cases involving occupational hearing loss were reported among workers in the manufacturing sector.” Compressed air and pneumatic equipment are significant contributors to the noise exposure. OSHA created a chart to show the maximum allowable noise exposure.  This chart shows the exposure time and noise limits before requiring hearing protection.  The EXAIR Super Air Nozzles, Super Air Knives, and Super Air Amplifiers are designed to have laminar flow, which makes them 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 danger.  The most effective way is by eliminating the hazard or by 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 avoid any future fines or having to purchase additional personal protective equipment (PPE), it will be less expensive and a preferred safety method to purchase an EXAIR product.  As in that above Hazard Hierarchy of Controls chart, EXAIR products are that engineered solution.  If you would like to improve the safety in your facility, move up to an engineered solution, and reduce energy costs; an Application Engineer at EXAIR can review your current blow-off devices.  Remember, safety is everyone’s responsibility. 

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

Mufflers to Protect Manufacturing Workers Hearing

Mufflers

Many manufacturing plants have a strong focus on safety for their workers.  One major safety concern that is overlooked is noise.   OSHA, Occupational Safety and Health Administration, has a directive that defines the noise exposure over time; 29CFR 1910.95(a).   For an eight-hour day, the maximum noise level is 90 dBA.  Hearing loss is irreversible, but it can be preventable.  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 engineered products to reduce noise levels in the work environment.  We offer Super Air Nozzles and Safety Air Guns for blow-off applications and pneumatic mufflers for discharge exhaust.  In this blog, I will cover the different types of EXAIR Mufflers that we offer.   

  1. 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.  The Reclassifying Mufflers can reduce the loud noise as well as collect any contamination from the exhaust air.
  2. Sintered Bronze Mufflers are simple in design, cost effective, and easy to install. They have a minimal back pressure to not restrict 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.
  3. 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.
  4. Heavy Duty Mufflers are used within aggressive environments.  They have an outer aluminum shell with an internal stainless-steel screen.  They protect components like valves and cylinders from contamination entering into the part.  And, the Heavy Duty Muffler can keep contaminant 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 compressed air system.  EXAIR has an engineered product to solve most of them.  On the Hierarchy of Controls for NIOSH, Personal Protection Equipment, PPE, is the least effective.  A better control would be to isolate your operators from the hazard with an engineered product.  EXAIR can offer that solution for many of your blow-offs and pneumatic discharges to reduce noise levels.  This would include; and not limited to; Super Air Nozzles, Safety Air Guns, Super Air Knives, and Mufflers.  If you wish to discuss further 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

Reduce Sound Levels With Engineered Compressed Air Products

A while back, I had the pleasure of assisting a customer with selection and implementation of our Super Air Nozzles, to replace open-ended blow offs on their machine tools. They installed the Super Air Nozzles after shutdown one afternoon. When he came in to work the next day (he arrived after production started), he thought there was a major problem in the shop, because (as they say in the movies right before something bad happens) “it was quiet…too quiet.” Turns out that, even though the goal was to reduce air consumption, they also reduced the sound level of the blow offs to an unexpected degree.

The copper tube used to have a crimped end that was aimed at the part in the chuck. They simply cut it off and used a compression fitting to install the Super Air Nozzle.

Another time, a metal stamping plant tried out our Model 1122 2″ Flat Super Air Nozzle on a stamping machine, using a Stay Set Hose to replace the copper tubing that was used to eject parts from the platen. They did the switch in the middle of the day…the operator at the adjacent machine noticed the dramatic noise level drop and came over to see what was wrong. Then he asked when they were getting one for HIS machine.

This loud & inefficient copper tubing blowoff was just Model 1122 2″ Flat Super Air Nozzle (and a Stay Set Hose) away from being quiet and efficient.

Both of these solutions originated with calls to discuss ways to reduce compressed air consumption costs. The fact that noise levels went down so dramatically just added to the benefits of using engineered compressed air products from EXAIR. If you’d like to find out how to make your electric bill – and your shop noise level – go down, give me a call.

Russ Bowman, CCASS

Application Engineer
EXAIR Corporation
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