Plan 76 is a leakage management piping plan intended for use when the leakage from the primary seal will be a gas. In this arrangement the vent is located at the top of the outer seal gland and is routed to a flare or vapor recovery system through an orifice.  An upstream pressure alarm provides notice of excessive leakage. API requires a minimum orifice diameter of 1/8” (3 mm) but smaller sizes may be necessary to provide a realistic leakage alarm point. It is recommended that the high pressure alarm switch be set at 7 psi (0.5 bar) above the mean operating condition in the flare or vapor recovery system.