Protect Personnel from Noise with Engineered Products

Sound can be defined as vibrations that typically travel as an audible wave through mediums that can be a gas, liquid or solid. For this blog we will concern ourselves with sound travelling through a gas (atmosphere) in an industrial setting.

Sound is energy that travels in waves and is measured by its frequency (cycles per second) and amplitude (intensity). A common unit of measurement for sound energy is the decibel. The decibel (abbreviated with dBA) is a unit-less number that is based on the logarithm of a known measured quantity to a reference quantity. Without reciting the equation for every increase of 3 dBA is a doubling of sound energy or twice as loud.

Since our focus is on industrial sound one might question why be concerned at all, after all sound emanates from most machines and devices. The reason for concern is that there are OSHA regulations regarding the amount of time workers can be exposed to different levels of sound in their workday as illustrated below. These limits are in place to protect personnel from Noise Induced Hearing Loss or NIHL. When the damage to anyones hearing is caused by their profession, it is also referred to as Occupational Hearing Loss or OHL.

After monitoring for noise, NIOSH and the CDC next recommend administrative controls to minimize or eliminate the noise hazard (click for their helpful PDF). This would include the use of noise reducing EXAIR products like Super Air Nozzles, Air Knives and Air Amplifiers.

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OSHA Maximum Allowable Noise Exposure

When considering the many items in an industrial setting that produce loud sounds the list would be exhaustive. Many of them simply produce loud sounds that can’t be eliminated or reduced while on the other hand there are some that can. Some of the noisiest offenders that plants have control over are air powered tools and open tube blow-offs.  Eliminating inefficient methods of part blow off & part cleaning with an engineered solution allows a company to significantly reduce the level of sound in their plant, improve worker safety and save money on compressed air consumption.

Employers are required to provide hearing protection to employees whom are exposed to sounds above 90 dBA on a Time Weighted Average (TWA). Without digressing into the formulas TWA calculates a workers daily exposure to occupational sounds by taking into account the average levels (in dBA) and the time exposed to different levels.  This is the how OSHA assesses workers exposure and what steps should be taken to protect the workers.

To conclude, plants need to be mindful of the OSHA regulations for sound levels, time of exposure and that hearing protectors wear out. Earmuff seals can lose their elasticity and reduce their effectiveness and the soft pre-molded earplugs can wear out in a day and need replaced.  Keep a good supply on hand and OSHA suggests letting workers with noisy hobbies take them home for protection off the clock!

If you would like to discuss reducing noise or any EXAIR product, I would enjoy hearing from you…give me a call.

Steve Harrison
Application Engineer

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EXAIR Products: Silencing Mufflers Overview

OSHA Standard 29 CFR 1910.95(a), relating to permissible noise exposure levels, states that when employees are subjected to sounds in excess of 90 dBA, some type of control should be used to reduce the sound level. In an industrial setting, it’s very common to find the exhausting air from air operated devices such as actuators, diaphragm pumps or cylinders for example, to produce sound levels well above the allowable limits set forth in the Standard. EXAIR offers a variety of different Silencing Mufflers that help to reduce this  noise level, while also increasing operator safety.

 

Reclassifying Mufflers are available in 1/8″, 1/4″, 3/8″, 1/2″, 3/4″ and 1″ NPT sizes

EXAIR’s Reclassifying Mufflers offer noise reduction up to 35 dB and are available in sizes ranging from 1/8″ to 1″ NPT. These types of mufflers are often considered”dual-purpose” as they not only reduce the noise level but also remove oil from the exhaust airflow by incorporating a removable filter element.  The exhausting oil mist is reduced from 50 PPM (parts per million) to only 0.015 PPM, when the device is operated at 100 PSIG. In addition, there is a bowl on the bottom to capture any residual oil and a 1/4″ tube adaptor to allow for easy draining.

Sintered Bronze Mufflers are available in #10-32, 1/8″, 1/4″, 3/8″, 1/2″, 3/4″, 1″, 1-1/4″ and 1-1/2″ NPT sizes, as well as 1/2-20 UNF female for use with solenoid valves
Straight Through Mufflers are available in 1/4″, 3/8″ and 3/4″ MNPT x FNPT

Sintered Bronze Mufflers are a relatively low cost option, commonly used with air cylinders as they can be installed quick and easy. We offer 1o different sizes, ranging from #10-32 for small installations, up to 1-1/2″ NPT for larger scale applications. The noise reduction depends on the size of the muffler and back pressure, which can occur from dirt or particulate clogging the muffler, restricting the exhausting airflow from passing through the porous sintered bronze.

Our Straight Through Mufflers are made of corrosion resistant aluminum and are lined with a sound absorbing foam, capable of reducing noise levels up to 20 dB. We offer 3 different sizes, 1/4″, 3/8″ and 3/4″ NPT, with a male thread on one end and female thread on the other. We incorporate this muffler design into our Cold Guns and Adjustable Spot Coolers and they are commonly used with our Vortex Tubes, Cabinet Cooler® Systems and E-Vac® Vacuum Generators as well.

Heavy Duty Mufflers are available in 1/4″ and 3/8″ FNPT

Lastly, the Heavy Duty Mufflers feature an internal, 50 mesh stainless steel screen, to protect against contaminants in the airflow,  and a corrosion resistant aluminum outer shell. In most cases, the sound reduction can be as high as 14 dB and we offer 2 different sizes, 1/4″ and 3/8″ FNPT. These types of mufflers are regularly used on the hot air exhaust of our Vortex Tubes.

For help with product selection or to discuss a particular process, please contact one of our application engineers at 800-903-9247.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

Excessive Noise Levels Cost You Health and Money

OSHA and the CDC make these statements about noise exposure. Did you know almost 30 million American workers are exposed to dangerous noise levels almost daily, with over 72% of those reported incidents happening in manufacturing environments? Noise induced hearing loss is the second most self-reported occupational injury and since 2004, over 125,00 workers have experienced some level of permanent hearing loss. Excessive noise levels can also reduce productivity, contribute to increased stress levels, communication errors and an irreversible condition called tinnitus or a constant ringing in the ears. In fact, disability claims associated to occupational hearing loss has risen to over $ 242 million per year.

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Noise Induced Hearing Loss Is One Of The Most Common Occupational Diseases.

In effort to reduce worker exposure and increase safety, OSHA introduced Standard 29 CFR 1910.95(a). As the standard reads, employees that are subjected to sounds levels in excess of 90 dBA, some type of engineered controls should be implemented by either using some form of PPE – Personal Protective Equipment, i.e. – earplugs, earmuffs, etc. or replacing the loud device altogether with an engineered solution that is designed to reduce the sound level. When a company is found to be in violation of the Standard, OSHA hands down costly fines, in some cases nearing almost $5,000. While providing PPE may seem like the inexpensive, “quick” fix, it actually could lead to more overall cost in the form of fines or claims, as now it is the responsibility of the operator to utilize the equipment provided. The better choice of the 2 options mentioned above, would be to replace with an engineered solution that is designed to lower the sound level.

OSHA Noise Level
Noise Level Chart per OSHA Standard 29 CFR 1910.95(a)

Take for example, a section of pipe with drilled holes across the length to cover wide area applications or an open end pipe or tube for more focused blowoff, both of which typically produce sound levels in excess of 100 dBA which would limit work exposure to only a couple hours per the above chart.

EXAIR’s Intelligent Compressed Air Products are designed to meet or exceed this standard. Our products entrain large volumes of surrounding air across the profile of the device which helps to reduce wind shear, ultimately lowering the sound level. When considering replacing drilled pipe, take a look at our Super Air Knife. The Super Air Knife produces a much lower sound level at only 69 dBA which is well under the allowable exposure times set forth by OSHA. Depending on the pipe or tube size, these can quickly and easily be replaced with one of our Super Air Nozzles by just adding a fitting to the existing line. For instance, our Model # 1100 Super Air Nozzle, with a sound level of 74 dBA, again falls well within the OSHA Standard.

sound-level-comparison
Sound Level Comparison

In addition, we offer our Digital Sound Level Meter to measure sound levels ranging from 35 to 130 dBA. The unit features a backlit LCD display, fast and slow response times, Max hold and includes NIST (National Institute of Standards and Technology) certification.

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Model 9104 Digital Sound Level Meter

For assistance in gaining OSHA compliance relating to your compressed air needs, please give us a call.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN

 

 

 

 

EXAIR Webinar: Simple Steps for Big Savings

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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

Chain-Chain-Change, Change Out That Drilled Pipe…

Life is full of change.  It might sound trite, but truer words were never spoken.  I used to get up around 6:30 on work days.  Now, thanks to my son’s middle school schedule, I’m usually seeing him out the door at that time.  Getting up earlier was certainly a difficult change at first, but it’s had its benefits.  Not the least of which is spending a little extra time with the boy in the morning.

One of our favorite things to do while eating breakfast is to watch the ‘How things are made’ types of shows. Of course, watching these types of shows with an engineer has its downside.  While we can usually explain exactly what’s happening in the process of whatever is being made, the problem is that we often do.  Meaning we wind up talking over the program, which, ironically, is one of my greatest pet peeves.  Speaking of change, guess that’s something I need to work on…

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At any rate, this morning we saw a show on making saltines.  At the sight of the copper pipe positioned near where the cracker dough comes off the die-cut wheel, I knew exactly what was up. ‘They’re using drilled pipe! That’s not safe and a HUGE waste of compressed air!  That’s the perfect application for a Super Air Knife!”  Guess watching these programs with an EXAIR engineer has an additional risk: We can get a little over-excited when we see OSHA violations and wastes of compressed air! I think I about made my son jump out of his gym shorts, but he’s watched these sorts of shows with me before.  He knew the risks…

Life is full of change, and while perhaps I can get better at not talking while the TV show is on, I doubt I’ll ever stop cringing at safety violations and wasting compressed air.  Do you have drilled pipe in your plant?  If so, you could be in violation of multiple safety standards and are definitely wasting money on compressed air.  EXAIR can help you minimize harmful noise levels and keep you in compliance with OSHA’s dead-end pressure standard. Please give EXAIR a call to begin saving air and increasing safety!

Dan Preston
Engineer-at-large
DanPreston@exair.com
1-800-903-9247

 

 

Safe Trip

Just getting back in the swing of things after being on vacation last week. My family, along with my mother, went on a 7 day Eastern Caribbean cruise which included 3 days at sea and 3 days at different ports. Our port stops included the Bahamas, San Juan Puerto Rico and the island of St. Maarten. My wife and I have cruised several times and have already visited these islands, but with this cruise being our son’s and my mother’s first, we thought we would try to experience some different things.

Our last port was St. Maarten, where “we” (my wife and mother) planned our day of shopping and having an authentic lunch at a local restaurant. With the shopping portion of the day complete, we started asking locals for a good place to have lunch. We met a local who ran his own taxi company and recommended we have lunch at Maho Beach but it was going to be a 20 minute taxi ride. When we arrived, for some reason the area seemed somewhat familiar and then it hit me…. I’ve seen this place on TV! Their airport sits right on the edge of the island and arriving and departing planes basically fly right over your head while sitting at the restaurant/bar or swimming at the beach.

People line up along the road and fence line and wait for the next plane (the restaurant/bar has arrival and departure screens and will yell out when a large commercial jetliner is approaching), making it a very crowded area. Due to the potential jet blast coming from the engines there are safety signs posted that people ignore. I did ask one of the restaurant/bar managers if safety is such a concern, then why do they allow people to line up and he said “all they can do is warn people, if they want to subject themselves to injury, then that’s on them”. I don’t want to see anyone getting hurt, but I must admit, it is a little humorous to see people get blown all over the beach. Needless to say, we stood a good distance away.

St Maarten02_Maho Beach38Safety signmaho-beach-st-maarten

In all seriousness, safety should be a primary concern. Is your plant currently practicing safety when dealing with compressed air? Open pipes, tubes or drilled pipe can consume large amounts of compressed air, and exceed the pressure and noise level thresholds outlined by OSHA. And we are all aware that personnel don’t always abide by the safety rules – much like ignoring a safety sign.

At EXAIR, our customer’s safety is of utmost importance. All of our intelligent compressed air products meet or exceed the OSHA standard 1910.242(b) for safety.  This means that you can still operate the devices at 80 psig while not having to worry about an operator injuring themselves with the compressed air.  This is not just for one product line, but ALL of the compressed air products that we manufacture.

EXAIR products also meet or exceed the OSHA standard 29 CFR 1910.95(a) for maximum allowable noise exposure levels.   The chart for allowable noise level exposure is below. Occupational hearing loss is a serious issue in manufacturing, in fact, it is the most commonly recorded illness is manufacturing. Engineering controls, like replacing open air lines with engineered air nozzles, are one of the top recommendations to solve the problem. Engineering controls can effectively eliminate the problem of people forgetting, refusing, or ignoring safety processes.

OSHA Noise Level

By implementing the EXAIR engineered solutions into your facility you can effectively lower the noise level cause by unsafe compressed air blow offs and possibly eliminate the need for hearing protection all together.   In my experience any time an operator doesn’t need to wear hearing protection or you can make their surrounding environment a little quieter, they tend to be a little happier which, always leads to better production. Again, many resources back this up, loud noise can also create physical and psychological stress.

These are just two of the standards that EXAIR will never take a vacation on.   Every product that EXAIR designs must be safe for operator operations, whether that be through pressure output or through the noise level it creates.

Contact one of our applications engineers to see how we may be able to improve similar safety concerns at your facility.

Justin Nicholl
Application Engineer
justinnicholl@exair.com
@EXAIR_JN