“My operators are complaining that our air guns are too loud, how can you help me?” – is a very common inquiry we receive here at EXAIR on almost a daily basis. Many open end blowoffs or air guns fitted with nozzles that have cross drilled relief holes create high pitch wind shear, resulting in excessive noise levels, sometimes exceeding 100+ dBA. This not only is a safety concern but also an OSHA violation.
Loud noises and the length of exposure time can lead to significant health concerns such as long term hearing loss, increased stress levels and potential injury due to lack of concentration. The Occupation Safety and Health Administration (OSHA) introduced Standard 29 CFR 1910.95(a) as a way to protect workers from job related injuries associated to potentially dangerous sound levels. Per the Standard, at 90 dBA an operator is limited to a maximum of 8 hours of constant exposure. As noise levels increase, the allowable exposure time decreases, in some cases slowing production, costing a company on their bottom line.
EXAIR’s Air Nozzles are engineered so they entrain surrounding air across the profile of the nozzle, which produces a smoother airflow, ultimately reducing wind shear, resulting in much lower sound levels, meeting the OSHA Standard.
In addition, our Air Nozzles also meet the OSHA Standard 1910.242(b) for 30 PSI dead end pressure. All of our engineered Air Nozzles provide a relief or a safe path for the air to exit if the nozzle were to be blocked or pressed against an operator’s body so the exiting air pressure will never reach 30 PSIG.
All of EXAIR’s Air Nozzles are available with standard NPT threads to easily adapt to existing air guns. We also off our full line of Safety Air Guns which are fitted with our engineered nozzles, providing an “off-the-shelf” OSHA compliant solution. For help selecting the best product to replace your existing device or if you have a new application you would like to discuss, give us a call at 800-903-9247.
Many times we receive calls from customers that fall right in line with our focus here at EXAIR – providing Intelligent Compressed Air Products that improve overall safety for operators and plant personnel in industrial operations as well as reduce compressed air usage, ultimately lowering energy costs. Such was the case last week when I received an inquiry from a customer who was looking for a handheld device that could easily attach to their existing air hose to replace the loud and inefficient homemade air nozzles they are currently using to blow off steel chips and coolant from their saws and drills. Their current set up includes a combination of smashed air guns, similar to the one shown below, some small open tubes and cheap plastic nozzles. The blowoffs were working but their operators were starting to complain about excessive noise during operation and notice the compressor in the area was running continuously during the cleaning cycle. Their first proposed solution was to lower the supply pressure which did lower the sound level and air usage somewhat, but now the exiting airflow wasn’t powerful enough to clear the debris. After doing an internet search they decided to reach out to EXAIR for assistance.
All of the Safety Air Guns we offer utilize our Air Nozzles which are engineered to meet or exceed OSHA Standard CFR 29 – 1910.95(a) for allowable noise exposure levels. As the Standard reads, when employees are subjected to sounds in excess of 90 dBA, some type of engineered controls should be used to lower the sound to a permissible level. Prolonged exposure to excessive noise can result in serious health issues, like tinnitus or a constant ringing of the ears, as well as stress and reduced productivity. In addition, our engineered Air Nozzles cannot be dead ended, meeting OSHA Standard 1910.242(b). With the design of our Air Nozzles, there is always a safe path for the air to exit so the outlet pressure will not reach 30 PSIG if the nozzle exhaust were to be blocked or pressed against the skin. Due to this design, our units are safe to operate at higher pressure, resulting in a high velocity, forceful airflow.
For this application, I recommended the customer use our Model # 1210 Soft Grip Safety Air Gun. This particular unit incorporates our Model # 1100 Super Air Nozzle which produces a low sound level of 74 dBA, well within the OSHA guidelines, and consumes only 14 SCFM @ 80 PSIG while having the necessary power to solve their application.
Last week, I received an email from a satisfied customer, after he had already purchased our product. Come to find out this customer had not spoken to an application engineer during the planning stage to make their purchase. With our excellent resources listed at EXAIR.com, the customer was able to fulfill his application without even speaking to us. After his initial email of thanks, he also shared with me some details of his application that I want to share with you today.
The customer works as a machinist at a large aircraft part manufacturer. The parts require a very tight tolerance. A sample of each part needed to be gauged and measured in an automatic thread gauging machine or a coordinate-measuring machine (CMM). Their machining process required a water based flood coolant, so each part would be coated in water based coolant and chips, which needed to be remove before gauging. Before visiting EXAIR’s site, the company used a variety of homemade and commercial blow offs, as safety air gun tips. Here is a photo of (20) of the (25) nozzles the customer was using.
As you can see, the nozzles vary in design purpose, flow and safety. Most of the nozzles feature a cross drilled hole or a secondary escape path, but not all of the nozzles do. Any nozzle without a secondary relief port violates OSHA standard CFR 1910.242(b), so replacing some of the nozzles increased the safety in the plant. Secondly, these nozzles are wasteful in their use of compressed air because some were designed as liquid nozzles and have large exit holes. A hole that is 1/8″ in diameter at the nozzle outlet can consume up to 21.4 SCFM of compressed air at 80 PSIG. For comparison, the model 1103 Mini Super Air Nozzle with a 1/8″ NPT inlet will flow 10 SCFM at 80 PSIG, which would be a 53% compressed air savings. In 24 running hours, the 1103 nozzle will save 16,416 Standard Cubic Feet, which the plant spent $4.10 for a standard industrial compressor to produce (The standard for compressed air cost is $0.25 per 1,000 SCF). Replacing just one 1/8″ drilled hole with 1103 Mini Super Air Nozzle saves the aircraft company $1,026 over 250 working days running 24 hours a day.
Neither of these were the real reason that the customer emailed to thank us though. He was actually an office employee just entering the work force. Starting in June until after the company finally acquiesced to his request to buy a better, quieter nozzle near the end of July, he had left work needing an aspirin to relieve the headache he acquired due to the noise from these other nozzles. The nozzles the machining center had been using would create noise levels between 88-100 dBA at 80 PSIG of inlet pressure. For reference OSHA mandates that employees are required to wear hearing protection, if they are exposed to noise levels over 90 dBA over an 8 hour work day. The employees doing the machining wear hearing protection, but the employees in the office were still exposed and affected by the noise level. This is just one anecdotal example, but everyday more and more research shows that noise exposure has a negative effect on our health and productivity in the workplace. If you are interested in more information here are some links to a number of studies/research – please read this, here or this.
Anyway, that’s enough of my soapbox. The company purchased 25 of EXAIR’s 1103 Mini Super Air Nozzles and utilizing the same guns they were currently using saw between a 10-15 dBA decrease in noise levels near the work stations. Here is a photo of one of their setups with the model 1103 installed on one of their current air guns.
We know that every time they squeeze that air gun trigger they will be using less compressed air than before, and we know they are now in compliance with OSHA. But the best benefit for EXAIR is we know that the engineer took the time to email us to thank us for taking away his headache everyday. That’s enough for me.