In February of 1972 OSHA released a standard to improve worker safety when operating handheld compressed air devices being used for cleaning purposes. This directive focuses around human skins permeability. That is, if you were to take an open ended pipe that had compressed air being discharged over 30 psig it can actually push through the skin and create an air embolism.
Air Embolisms are extremely painful, and in extreme cases, can be deadly. The risk associated with an air embolism can be mitigated by following the OSHA directive and reducing the downstream pressure of an air nozzle or nozzle pressure below 30 psi for all static conditions. Dead ending is when the passageway for the air becomes blocked and turns a dynamic flow of air into a static flow. This is in the event the pipe, nozzle, lance, etc. becomes blocked by a human’s body. This is a directive that all Intelligent Compressed Air® products from EXAIR focus on meeting or exceeding.
Our Air Nozzles and Jets video shows a great depiction of how this can be achieved with our engineered design of nozzles. The recessed holes and the fact that there are multiple passages for the air to exit are easy to see on the nozzle. Products like the Super Air Knife may not be so easy to see but the way the air knife cap overlaps prevents the Super Air Knife from being dead ended in the event an operator comes into contact with the discharge air.
Even though this directive was created in 1972 it continues to be at the forefront of industrial environments. I have even been to a custom artwork facility that was effected by this standard because they would use a handheld blowgun to remove dust and debris before matting and framing artwork with glass. They also removed dirt and dust from the frames before paint. This wasn’t your typical manufacturing environment yet they were still held to the same standards and were made safe by implementing engineered solutions such as our Super Air Nozzle.
If you would like to discuss how we can help increase your operator safety and ensure you meet or exceed OSHA 29 CFR 1910.242(b), please contact an Application Engineer today.
EXAIR products are used in countless applications across all facets of industry, we have been working to compile some in a easy to read Application Database on EXAIR.COM!
Today I wanted to cover a few application successes from within Foundries.
The first example is from a company who manufactures flux for aluminum processing. They were experiencing conveyor belt jam ups because not all the material would fall off at the tail end of the belt. What adhered to the belt would be carried over on the return, fell off due to gravity and vibration, and was causing build up underneath and jamming the belt. The Model 110036 36″ (914mm) Super Air Knife was installed on the end of the conveyor blowing off any tramp material as the belt came around the head pulley. This consolidated the debris to one area where they could easily reach it for removal. This all but eliminated maintenance and downtime.
A manufacturer of aluminum rods was having problems with removing drawing die lubricant from aluminum bar being cut to length. The lubricant was causing the bar to slip in the grippers, causing the bars to be cut short. Passing the bar through a Model 2402 2″ (51mm) Super Air Wipe effectively removed the lubricant, and eliminated grip slippage.
The last customer operates an aluminum foundry. A small actuating cylinder’s seals were failing frequently, due to the heat from a nearby furnace. Using a Model 3230 Medium Vortex Tube, they are able to direct a flow of cold air onto the cylinder, keeping the elastomer seals cool, which greatly extends their life.
If you have questions about any of the quiet EXAIR Intelligent Compressed Air® Products, feel free to contact EXAIR and myself or one of our Application Engineers can help you determine the best solution.
One of the most dangerous things you can do is depressurize a line full of a pressurized gas. If the charge pressure is high enough, it’s going to come roaring out, with tremendous force and velocity. Anything in its path is subject to that force & velocity. Objects small enough to become entrained in its flow can become hazardous projectiles. The noise it creates can be literally deafening. If the point of discharge is accidentally jammed against your body, the pressure can get through your skin. As if that wasn’t scary enough, the gas then has a free path inside your body…they call that an embolism, and it can kill you.
Why on earth would anyone want to do that on purpose? Well, it happens every day, in factories, businesses, and homes all over the world, when people operate compressed air operated blow off devices. Of course, there are numerous factors that can drastically reduce the risk of injury associated with compressed air blow off devices.
One of these is mandated by the government. The Occupational Safety and Health Administration (OSHA) regulates the outlet pressure of any compressed air device used in industry for cleaning purposes. Keeping the outlet pressure low mitigates the risk of puncturing the skin. There are various methods of compliance with this regulation:
Regulate the supply pressure to less than 30psig. This absolutely complies, but it severely hampers your ability to get much done, as the air flow will be too weak to blow off anything but lightweight debris, from a smooth, dry surface, with the device pretty much right up on top of it.
Use a device that provides a relief path for the air flow if it was to become blocked or obstructed. EXAIR engineered Air Nozzles are designed to do this…you can supply them with higher pressures but they provide a relief path for the air, meaning they can’t be blocked or dead-ended.
The same regulation – OSHA 1910.242(b) – also addresses the airborne projectile problem by mandating the use of appropriate chip guarding. There are a number of ways to do this as well…chief among these is personnel protective equipment (PPE). At a minimum, you absolutely, positively should be wearing safety glasses with side shields whenever you have a blow off device in your hand (and so should anyone working near you, for that matter). If an operator is blowing off small, sharp shards, an OSHA inspector is probably going to get grumpy if they’re not wearing a full face shield, long sleeves, and maybe even a durable apron. Alternately, the blow off device could also be fitted with guarding as well…something like the Chip Shields that are available for most EXAIR Safety Air Guns. These polycarbonate dish-shaped shields fit on a rigid extension between the Safety Air Gun and the Super Air Nozzle, and can be positioned at an optimal distance to keep solid debris and liquid being blown off away from the operator.
Another OSHA Standard – 1910.95(a) is there to protect operators against that literally deafening roar associated with unregulated discharge of compressed air. While cross-drilled nozzles (most easily seen in the lower left hand image above) provide a relief path to keep the outlet pressure at a safe level if they’re dead-ended, they’re still for all intents & purposes, an open-ended blow off…and quite loud. EXAIR Super Air Nozzles reduce the sound level of their air flow by design…the entrained air (which makes them so efficient) also forms a lower velocity barrier layer in the flow, which makes them extraordinarily quiet. In fact, all EXAIR Super Air Nozzles except our largest High Force models comply with OSHA limits for 8 hour noise exposure limits. Most callers that we talk to about applications for those are in areas where hearing protection is mandated anyway…if you need more than 4 pounds of blowing force, you’re probably wearing ear plugs already.
If you use compressed air for cleaning, drying, blow off, etc., you really need to do it safely, and in compliance with published & established safety standards. OSHA WILL fine you otherwise, and, even worse, someone could get hurt. EXAIR Corporation is devoted to helping you get the most out of your compressed air usage, and safe use is key to that. If you have any questions about it, give me a call.
Russ Bowman, CCASS
Application Engineer EXAIR Corporation Visit us on the Web Follow me on Twitter Like us on Facebook
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.
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.
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.
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.
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.