[martin417]

A quick exhaust valve, sometimes called a "quick dump" valve (no jokes please) is a 3 port valve, "in", "out" and "exhaust". when you pressurize the "in" port, air flows through to the "out" port. When you release pressure on the "in" port, air from the "out" port flows freely though the "exhaust" port, therefore it doesn't have to flow back to the solenoid valve through all the tubing and fittings. A very useful item. Unfortunately, I interpret the rules to say that it is not legal for FIRST use. <R72> is a list of items expressly permitted (in addition to the KOP items) for pneumatic system use. If it isn't listed in <R72> it isn't permitted. A quick exhaust valve doesn't fit any of the descriptions in <R72>, therefore, is not permitted.