Your engine runs a pump when you are delivering compressed gas. Should you turn off your engine before or after you unhook the hoses after finishing that delivery?
Turn it off before unhooking.
If your engine is required to be on when you are pumping a load of compressed gas, you are always adding an extra layer of danger to a situation. As soon as the delivery is completed, make sure that you turn off the engine before you unhook any hoses.
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