Allowable Gas leak rate : API standard for X-mass tree

[abdulasad]

I am doing am assignment on well integrity management of my HT field. I want to know that what is the allowable leak rate for dry gas wells when checking the integrity of Gate valves of X-mass trees. What does API standard define in this matter.

Thanks & Regards

[abdulasad]

also if there is any criteria in terms of pressure drop instead of scf/hr ???