Tag: noise

Noise In The Workplace

Published on by Russ BowmanLeave a comment

The Center for Disease Control (CDC) estimates that 22 million workers are exposed to potentially dangerous levels of noise at work every year. That’s “only” about 15% of the total number of people who are employed in the United States, but if you’re one of them, you should absolutely know the risks, and how to protect yourself. Obviously, high noise levels can cause hearing loss, but do you know what else it causes?

  • Cardiovascular disease. Constant noise exposure causes stress, and stress triggers the release of hormones that increase your blood pressure, which can lead to ischemic heart disease, strokes, and arrhythmia.
  • Sleep disruption. Studies show chronic noise exposure during the day can cause difficulty falling asleep, shortened sleep cycles, and frequent wake-ups during the night. All this leads to chronic fatigue and a host of long-term health issues.
  • Immune system suppression. While the exact nature of the relationship is unclear, recent studies have indicated that noise can cause changes in our immune systems.
  • Cognitive impairment: Continued noise exposure causes memory impairment, attention deficits, and reduced concentration.
  • Mental health issues. Not only does continued noise exposure release hormones like cortisol & adrenaline (causing the chronic stress that’ll literally break your heart; see above), it directly influences anxiety, depression, and irritability.
Don’t let this happen to you.

So, how do we protect ourselves? If you said “ear plugs,” you’re not wrong…but did you know that hearing protection in the form of personnel protective equipment (PPE) is considered the LEAST effective method of mitigating noise exposure? The National Institute for Occupational Safety and Health (NIOSH, a sister agency of the Occupational Safety and Health Administration, or OSHA) developed a hierarchy of controls…a “good, better, best” framework, if you will, of methods to address workplace hazards:

Even though hearing protection (the PPE in this case) is least effective, the intent of the hierarchy graphic is not to dismiss it, but to categorize it as a last resort. If all else fails (or, more often, comes up short,) ear plugs are your – and your hearing’s – best friend.

If the source of the noise cannot be eliminated (and let’s face it, an awful lot of industrial processes are necessarily loud), the next best thing to do is to substitute a quieter method or device. That’s where EXAIR comes in: the design of our engineered Air Knives, Air Nozzles, and Air Amplifiers exploits certain principles of fluidics to mitigate the noise levels associated with the rapid depressurization of compressed air when it’s blown for cleaning, drying, cooling, etc. The key to this is entrainment:

EXAIR Intelligent Compressed Air Products such as (left to right) the Air Wipe, Super Air Knife, Super Air Nozzle, and Air Amplifier are engineered to entrain enormous amounts of air from the surrounding environment.

While this entrainment makes EXAIR products EXTREMELY efficient (the compressed air consumption ends up being a fraction of the total developed flow), it also creates a low velocity boundary layer around the primary high velocity & forceful airflow. This layer attenuates the sound level of that high velocity flow.

Compressed air use can be loud, wasteful, and dangerous, but it doesn’t have to be. If you’re looking for a quiet, safe, and efficient solution for your use of compressed air, give me a call.

Russ Bowman, CCASS

Application Engineer
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Industrial Safety: Compressed Air

Published on by John BallLeave a comment

At EXAIR, we have a statement that says, “Safety is everyone’s responsibility.”  EXAIR builds its name around 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 compressed air systems, 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

Here is an example of a nozzle that is dangerous.  As you can see, there is only one path where the air can pass through.  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 compressed air cannot escape if it is blocked by 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 that 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 cannot be blocked by your skin.  So, you can use the EXAIR Super Air Nozzles safely above 30 PSIG (2 bar) and remain OSHA compliant.

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 the compressed air to escape, but now the issue is noise levels.  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 exposure time and noise limits before hearing protection is required.  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 Soft Grip Safety Air Gun has a sound level of only 74 dBA, well under the noise exposure limit for 8 hours.

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 much safer to purchase EXAIR products.  If you would like to improve the safety of your facility 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

Photo: Industrial Security Signal by DavidRockDesign.  Pixabay license

The Trick To Adding Sound Levels Of Multiple Sources

Published on by Russ BowmanLeave a comment

If I put a 10 pound weight on a scale, the scale will read 10 pounds. If I put another 10 pound weight next to it, the scale with now read 20 pounds.

If I have $10 bill in my pocket…well, that’s a LOT more cash than I usually carry. But if I somehow come into possession of another $10 bill and put it in my pocket, now I have $20. And it probably won’t be for long.

If there’s an EXAIR Model 1100 Super Air Nozzle supplied with compressed air at 80psig, and my Sound Level Meter is reading a level of 74 dBA, and I hook another one up right next to it, my Sound Level Meter now reads about 78 dBA.

Wait, what? Did we just break math there? You, and your ears, will be happy to know that there’s perfectly valid math behind the third (as well as the first two) statements above. The third one’s just a little different, that’s all.

See, sound power (that’s “how loud” sound is, as measured at the point of generation) and sound pressure (“how loud” it is, as measured at the point where it’s heard) are both quantified in units called decibels. And, unlike mass or wealth (the first two examples above), which are linear & additive, measurement of sound power & pressure is done on a logarithmic scale. That means simple arithmetic won’t work…we have to use a logarithmic equation to ‘add’ those sound levels together. It looks like this:

Combined Sound Level (dBA) = 10 x log10[10SL1/10 + 10SL2/10 + 10SL3/10 …]

Where “SL1”, “SL2”, “SL3”, etc., are the sound levels, in decibels, for the “noisemakers” in question. So, for the two Model 1100 Super Air Nozzles, generating 74 dBA each:

10 x log10[1074/10 + 1074/10] = 77.65 dBA

And just to prove the math works, we made a video of a real live test:

All EXAIR Intelligent Compressed Air Products are engineered & manufactured to be safe, efficient, and as quiet as possible. If you’d like to find out more, give me a call.

Russ Bowman, CCASS

Application Engineer
EXAIR Corporation
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Sound Levels in Your Facility

Published on by Jordan T ShouseLeave a comment

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

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