Requirement for Responsible Electrical Person (REP)

In the offshore oil and gas industry, the role of the Responsible Electrical Person (REP) is commonly seen. I was wondering if there are any standards or regulations that mandate the appointment of this role within the electrical team.

I am asking because I am considering a scenario where you have a normally unmanned platform that is only occasionally visited by a small crew of technicians. If your Electrical Technician is competent and authorised to work on the maximum voltage level present on the platform (415VAC in this case), would you still be required to have a separate person for the REP role? Or could the REP role be combined with the Electrical Technician's duties, with the intention that they handle all electrical isolations and operations whenever the crew visits the platform?

The asset cannot afford to allocate more than one position for the electrical team, so I would appreciate it if anyone could direct me to the standards or regulations that define the role, requirements, and responsibilities of a REP and if whether or not it's mandatory to have have one onsite.