46 CFR § 185.740
Periodic servicing of hydrostatic release units
April 15, 2021
(a) Each hydrostatic release unit, other than a disposable unit, must be serviced:
(1) Within 12 months of its manufacture and within 12 months of each subsequent servicing, except when servicing is delayed until the next scheduled inspection of the vessel, provided that the delay does not exceed 5 months; and
(2) In accordance with the repair and testing procedures under §160.062 in subchapter Q of this chapter, or other standard specified by the Commandant.
(b) Each disposable hydrostatic release unit must be marked with an expiration date of two years after the date on which the unit is installed.