Two Important Safety Factors When Choosing Air Nozzles

At EXAIR, we have a statement, “Safety is everyone’s responsibility”.  And we also manufacture safe compressed air products.  In the United States, we have an organization called Occupational Safety and Health Administration, OSHA, that enforces directives for safe and healthy working environments.  They do training, outreach programs, and educational assistance for manufacturing plants.  They will also enforce these directives with heavy fines for violations.  The two most common violations with compressed air are air guns and blow-off devices are described in 29CFR 1910.242(b) for dead-end pressure/chip shielding and 29CFR 1910.65(a) for maximum allowable noise exposure.

Here is an example of a nozzle that is dangerous.  As you can see, there is only one opening where the air can come out from the nozzle.  Other types of nozzles that would fall into this same group would include copper tube, extensions, and open pipes.

Unsafe Nozzle

They are dangerous as the compressed air cannot escape if it is blocked with your body or skin.  If operated above 30 PSIG (2 bar), these nozzles could 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 allows the air to escape and not be blocked by your skin.  So, you can use the EXAIR Super Air Nozzles safely even above 30 PSIG (2 bar).

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 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 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 time and noise limits before requiring hearing protection.  The EXAIR Super Air Nozzles, Super Air Knives, Super Air Amplifiers are designed to have laminar flow which is 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 dangers.  The most effective way is by eliminating the hazard or 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 stop any future fines or additional personal protective equipment (PPE), it will be much cheaper to purchase an EXAIR product.  And with the Hazard Hierarchy of Controls, the first method is to remove any hazards.  The last method for control is to use PPE.  In the middle of the hierarchy is for an engineered solution.  EXAIR products are that engineered solution.  If you would like to improve the safety in your facility with your current blow-off devices, an Application Engineer can help you.

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

Picture:  Safety First by SuccoPixabay License

The Soft Grip Super Air Scraper for Cleaning Tanks

A transport company was in the business of moving food product like powdered milk, sugar, salt, gluten, etc. to different Food and Beverage industries.  The tanks ranged from 1,700 to 2,200 cubic feet (47 to 61 cubic meters) in volume.  Because of condensation that can occur, some of the powdered materials would solidify on the sides of the tanks.  They found it occurring more often with the powdered milk.  So, they created a cleaning mechanism to use compressed air and an open pipe to clean the residue after each stop (reference above).  They realized quickly that with this type of cleaning nozzle was not safe and not efficient.  They could only scrape roughly 1” (25mm) at a time.  The noise level was too loud, the compressed air usage was too high, and the time to clean the tank was too long.  They contacted EXAIR to see if we could improve on their process.

Model 1144 Super Scraper Nozzle

The answer to the problem was the EXAIR Super Air Scraper.  This product uses a nozzle that combines a scraping blade with our 2” Flat Super Air Nozzle.  It uses the mechanical force of a blade with the force of compressed air to remove stubborn sticky materials.  The 3” (76mm) wide corrosion-resistant steel scraper is robust and durable, and they can be easily sharpened or replaced when worn.  To add flexibility to the Super Air Scraper, a shim set can be used to increase the blowing force.  This combination of the nozzle and the scraper is an effective and powerful way to remove material with compressed air.

Soft Grip Super Air Scraper

To get pressurized air to this patent-pending nozzle, EXAIR attached the Super Air Scraper to our Soft Grip Air Gun.  The Soft Grip Air Gun has an ergonomic soft handle and a full-grip trigger for hours of use without fatigue.   We include different extensions for hard-to-reach applications ranging from 6” (152mm) to 72” (1,829mm) in length.  With extensions that are 36” (914mm) and longer, EXAIR installs an additional foam grip sleeve.  This gives more leverage for scraping material at a distance like at the floor level.  Chip Shields can also be added to prevent blow-back on the users.

Scrape off, and blow away, stubborn debris with the Model 1244-48 Soft Grip Super Air Scraper.

For the company above, this was the perfect tool to improve their process.  I recommended the model 1244-48 Soft Grip Super Air Scraper which had a great length to reach the tank areas and a foam grip to comfortably force the blade under the powder residue.  With the compressed air, it helped to keep the area clean during scraping and aided with the areas that were really stuck.  With the 1” (25mm) pipe as compared to the 3” (76mm) blade, the cleaning for each tank was cut in half the time.  Also, with the open pipe, they were using roughly 150 SCFM of compressed air.  The model 1244-48 was able to cut this amount down to 22 SCFM at 80 PSIG.  This was a huge cost savings.  And as a bonus, the noise level was lessened from 100 dBA to 77 dBA; a much safer way to protect any hearing damage.

To give some other areas for the Soft Grip Super Air Scraper, they can be used for removing gasket material, tape, caulk, adhesives, paint, labels, and much more.  If you have a sticky situation at your facility, you can contact an Application Engineer at EXAIR.  We will be happy to discuss it with you.

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

Video Blog: Laminar and Turbulent Flows

I have written blogs about laminar and turbulent flows as related to the Reynold’s number.  Now, let’s demonstrate the difference between the two flows and the advantages of laminar flow from EXAIR’s engineered air nozzles; as demonstrated by our VariBlast Safety Air Gun.

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

Compressed Air Safety with EXAIR’s Intelligent Compressed Air Products

Compressed air is a necessary utility in any manufacturing environment. When used improperly, this compressed air can pose very real and serious dangers to your personnel. It’s imperative that you’re aware of the potential risks associated with the use of compressed air and educate yourselves and your operators to ensure you’re operating safely.

OSHA (Occupational Safety and Health Administration) provides standards designed to mitigate the risks of compressed air usage. If not adhered to, fines can be administered for each infraction. Fines are given out for each individual infraction. Meaning, if you have unsafe blowguns that are used in your facility you’ll get a notice for each individual gun that is identified during an inspection. Inspections aren’t something that happen often, but they will show up unannounced and often at the worst possible times.

OSHA Standard 1910.242(b) discusses the use of compressed air for cleaning and blowoff. It states that the use of compressed air for cleaning purposes is prohibited if the dead-ended pressure exceeds 30 psig. This phrase means the downstream pressure of the air nozzle or gun, used for cleaning purposes, will remain at a pressure level below 30 psig for all static conditions. In the event that dead ending occurs, the static pressure at the main orifice shall not exceed 30 psi. If it does exceed this pressure, there is a very high potential for it to create an air embolism. An air embolism, left untreated, can quickly impede the flow of blood throughout the body. This can lead to stroke, heart attack, and sometimes death.

With this in mind, there are only two options for staying within compliance of this standard. Either install an engineered solution that will reduce the air pressure to less than 30 psig if dead-ended, or regulate the pressure below 30 psig. For the vast majority of operations, regulating the input pressure below 30 psig is useless. The force and flow from the nozzle at this pressure is greatly reduced and likely not enough to be effective in most applications. All of EXAIR’s Safety Air Guns are designed so that the flow cannot be dead-ended. The fins on the Super Air Nozzles are not only useful in amplifying the force by drawing in ambient air, but they also prevent an operator from completely obstructing the airflow.

In addition to being concerned about dead-end pressure, OSHA 1910.242(b) also states that compressed air used for cleaning should include effective chip guarding. By this, they mean that some method or equipment must be installed that will prevent chips and particles from coming back into the eyes or skin of the operator. In addition to offering OSHA compliant nozzles and guns, EXAIR also has Chip Shields that can be installed onto any of our Safety Air Guns. The polycarbonate shields protect the operator from any flying debris while performing a drying or blowoff operation. Simply add a “-CS” to the end of any Safety Air Gun Model number to have a Chip Shield installed on the gun.

Hearing loss due to high noise levels is another common problem in many industrial facilities. Without the use of proper PPE, hearing loss can occur quickly. This is a serious concern as hearing loss is permanent and once the damage is done there’s no way to reverse it. Due to this risk, OSHA strictly enforces standard 29 CFR-1910.95(a).

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 directive discusses the effects of noise and limits exposure based on the dBA. The table below indicates the maximum allowable exposure time to different noise levels. Sound levels that exceed these levels should first be addressed by proper engineering controls such as isolating the source of the sound from personnel or replacing the cause of the sound with something like an engineered compressed air nozzle. When such controls aren’t feasible, proper PPE must be worn to protect the operator.

The Occupational Safety and Health Act of 1970 does not contain any provisions that allow for the approval or endorsement of equipment. Alteration or the misapplication of what was once a safe piece of equipment would create a dangerous scenario that is out of the control of the original manufacturer. Any nozzles or guns marketed as “OSHA approved” should immediately throw up a red flag. Identifying and implementing a safe, OSHA compliant solution rests in the hands of the manufacturer themselves. If you’ve got questions about compressed air safety or have an existing blowoff in place that does not adhere to this OSHA directive, give us a call. We’ll be sure to recommend a solution that will keep your operators and wallets safe!

Tyler Daniel
Application Engineer
E-mail: TylerDaniel@EXAIR.com
Twitter: @EXAIR_TD