25. Hydraulic cylinders in masts manufactured on or after 1 January 1978 and in outriggers manufactured on or after 1 January 1992 shall be equipped with release check valves which:
(1) prevent an accidental drop in pressure in the cylinder if the hydraulic line is ruptured;
(2) are installed on the hydraulic cylinder wall; and
(3) have no connection between the part of the hydraulic cylinder under pressure and the check valve.
It is not necessary to equip hydraulic cylinders with check valves if they are used only to adjust an outrigger.