What methods may be used to reduce air pressure below 30 p.s.i.?

OSHA requires that air pressure must be reduced to less than 30 p.s.i. for cleaning purposes (1910.242(b)). The regulation, however, does not give details as to how the pressure is to be reduced. Some of the methods OSHA suggests for pressure reduction include the following:

1. Reducing the pressure level of the air compressor.
2. Fitting the air source with a relief device which will release the air when the nozzle is dead-ended.
3. Installing an air nozzle with holes which will reduce the air pressure to less than 30 p.s.i. when the nozzle is dead-ended.

You can purchase commercially-made nozzles which are designed to reduce the p.s.i. to less than 30 or drill holes in existing nozzles, in which case you must be sure to test the nozzle’s air release with a pressure gauge.