30 CFR §250.815

1. (a)You must equip all new dry tree completions (perforated but not placed on production) and completions that are shut-in for a period of 6 months with one of the following:
   1. (1)A pump-through-type tubing plug;
   2. (2)A surface-controlled SSSV, provided the surface control has been rendered inoperative; or
   3. (3)An injection valve capable of preventing backflow.
2. (b)When warranted by conditions such as permafrost, unstable bottom conditions, hydrate formation, and paraffin problems, the District Manager must approve the setting depth of the subsurface safety device for a shut-in well on a case-by-case basis.