The Governor must notify the Secretary immediately if—
(a) an instrument of restraint referred to in regulation 13(1)(a), (b), (c), (d) or (f) is applied to a prisoner—
(i) for a continuous period of more than 18 hours; or
(ii) for a cumulative period of 36 hours in any 96-hour period; or
(b) an instrument of restraint referred to in regulation 13(1)(e) is applied to a prisoner for a continuous period of more than 15 minutes.