(1) Subject to section 161, the chief executive may direct that a detainee be segregated from other detainees for the purposes of this part.
(2) To remove any doubt, this section is additional to, and does not limit, the power to direct that a detainee be segregated from other detainees under any of the following:
(a) section 156 (Report etc by corrections officer);
(b) section 157 (Report etc by investigator);
(c) section 158 (Action by administrator).