Compressed air safety
When you choose to work with compressed air, you choose an energy source that is capable of storing large amounts of energy. Therefore, certain precautions must be taken to prevent accidents from occurring. Indications of maximum operating pressure, temperature, load, etc. must be respected and must not be exceeded.
Compressed air must not be allowed to come into direct contact with skin (the human body). Safety regulations regarding the use of compressed air are being reviewed in a number of countries. At present two countries, the USA and Switzerland, have implemented restrictions on the amount of compressed air pressure that skin may be directly exposed to.
Operators often use air guns to clean themselves of dust and grime during and after the working day. Using compressed air in this manner clearly involves the risk of air being pressed through the skin and entering the blood and creating a blood clot. A number of fatal accidents lie behind the restrictions that have been imposed.
In the United States, safety in the workplace is regulated by the OSHA. OSHA is an acronym for the Occupational Safety and Health Administration. The use of compressed air is covered in §1910.242 b, wherein it is stipulated that the pressure of compressed air that comes into direct contact with skin must not exceed 210 kPa (30 psi).
In Switzerland SUVA, Schweizerische Unfallsversicherungsanstalt, has imposed similar restrictions.
Every Silvent nozzle is designed to comply with these safety standards. The figure below illustrates that the nozzle cannot be blocked in a manner that closes off the entire opening (dead ending). Thus, the pressure that can be amassed will never exceed 210 kPa (30 psi).
Furthermore §1910.242 b states that some method or equipment must be provided to prevent a chip or particle, regardless of size, from blowing into the eye or against the skin of the operator or a fellow worker. This chip guarding may be separate from the nozzle, as in the case where shields or barriers are used. Generally speaking, the use of protective air cones provides adequate protection for the operator, but screens, baffles or shields may be necessary to protect fellow workers from exposure to flying chips or particles.
All of Silvent’s safety guns are designed to comply with these regulations.
EU Machine Directive
Within the EU, the regulations expressed in the Machine Directive 98/37/EC apply.
The directives set important health and safety standards regarding the design and manufacture of machine and safety components.
Even though compressed air nozzles are used in systems and machines governed by the Machine Directive, air nozzles are not specifically dealt with. Pneumatic components need not be individually CE approved according to the Machine Directive; in fact it is illegal to do so. For machine makers who must certify that their products comply with the Machine Directives, the specifications included in the catalog regarding temperature, pressure and voltage are sufficient for machine components.
Silvent will gladly answer additional questions regarding the Machine Directive.
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