40 CFR § 61.243-1 - Alternative standards for valves in VHAP service - allowable percentage of valves leaking.
(b) The following requirements shall be met if an owner or operator decides to comply with an allowable percentage of valves leaking:
(1) An owner or operator must notify the Administrator that the owner or operator has elected to have all valves within a process unit to comply with the allowable percentage of valves leaking before implementing this alternative standard, as specified in § 61.247(d).
(c) Performance tests shall be conducted in the following manner:
(2) If an instrument reading of 10,000 ppm or greater is measured, a leak is detected.
(e) If an owner or operator decides no longer to comply with § 61.243-1, the owner or operator must notify the Administrator in writing that the work practice standard described in § 61.242-7(a)-(e) will be followed.