Compressed Air and Safety

Warning

Compressed air is generally considered the fourth utility in industrial, commercial and back-yard settings.  It is used to power pneumatic equipment, cleaning surfaces, conveying materials, etc.  The compressor reduces the volume inside a chamber to increase the pressure.  The compressed air typically is contained in a reservoir tank for distribution to pneumatic equipment and devices.  Since air is a compressible fluid it has stored energy; and, if not used properly, it can be hazardous.  Most people perceive compressed air as harmless, but this is untrue.  It can be very dangerous.  Here are some potential risks when using compressed air:

  1. If the air pressure against the skin becomes greater than 30 PSI, air can penetrate through the membrane and cause an embolism which could be fatal.  The term used is Dead-End pressure, any end-use nozzle or blowoff product cannot exceed 30 PSI dead-end pressure.
  2. Hearing damage can occur from exposure to loud noises from compressed air exhausting from pneumatic equipment or devices.
  3. Proper use of Safety Air Guns and Safety Air Nozzles is a must. They should not be modified or tampered with.  For example, tying the trigger on an air gun for continuous blowing or modifying the nozzle to get a different blowing pattern.
  4. Compressed air can generate high velocities which can shoot chards of debris. The accelerated fragment can injure any part of the body even from bounce-back.
  5. If the air pressure is higher than the recommended rating for the equipment, uncontrolled eruptions can occur which can send broken pieces everywhere.
  6. When air hoses or lines are laying on the floor, near pinch points, or degrades from the environment, a break can occur causing unrestrained hose “whipping”.

Some safety precautions can be followed in your area when using compressed air products.  They may seem basic, but they are commonly overlooked.

  1. Verify that all compressed air components are rated to be used for the maximum line pressure.
  2. Use shut-off valves nearby to isolate the system from the main compressed air line.
  3. Have general inspection on your compressed air system to check for pipe degradation, leaks, faulty pneumatics, etc.
  4. When you go to repair items attached to the compressed air line, make sure to use proper lockout procedures to isolate and remove the hazardous energy.
  5. Remember that compressed air is not a toy and use proper PPE when required.
  6. If any pneumatically operated product is damaged, remove it from service and either repair it or replace it.
EXAIR Products

In 1970, Occupational Safety and Health Administration, OSHA, was enacted by the Department of Labor.  This organization was created “to ensure safe and healthful working conditions for working men and women”.  They created a set of laws and standards that they enforce with heavy fines and reoccurring visits if not followed.  The Department of Labor lists these laws under title 29 in the Code of Federal Regulations (CFR).  For general industry, these safety regulations are under part 1910 of 29 CFR.  To give a few examples, 29 CFR 1910.242b gives the explanation about dead-end pressure.  Under 29 CFR 1910.95a shows the maximum allowable noise exposure.  The reason that I noted these two OSHA standards as they are commonly overlooked with Safety Air Guns, and commonly fined by OSHA for improper nozzles.

Safety is everyone’s responsibility, and EXAIR products can be a key.  If you would like to discuss how to improve your workplace, you can contact an Application Engineer at EXAIR.     Because hazards and fines can be detrimental to your company when it comes to compressed air safety.

John Ball
Application Engineer

Email: johnball@exair.com
Twitter: @EXAIR_jb

 

Photo: Attention Warning Sign by Peter-LomasCreative Commons: CCO

 

 

OSHA Standard 1910.242(b) – Dead-End Pressure and Chip Guarding Explained

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. Take a look at the animation below to see how an air embolism can affect the body.

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.

sag-osha-compliant
The fins of the Super Air Nozzle allow air to escape and prevent dead-end pressure from exceeding 30 psig.

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.

1210peek-cs
EXAIR’s Model 1210-PEEK-CS with Chip Shield

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