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.

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).

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.

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 Succo. Pixabay License