Negative pressure leak test

A negative pressure leak test is employed to test for leaks in a flowmeter or other internal components of the anesthesia machine. With this test, all compressed gas flows are set to zero, then a suction bulb is attached to the anesthesia machine common gas outlet and repeatedly squeezed until it collapses, as shown in this photo. The bulb will not stay collapsed if there is a leak. (See topics describing the anesthesia machine for further information.)