10. When a person dies or is lost in circumstances in which an obligation to make a return of death arises under Regulation 8, the owner of the relevant installation shall as soon as is practicable and in any event within 48 hours of first becoming aware of the death or loss—
(a)if he was the employer of the dead or missing person, notify any person known to him to be, or nominated to him as, the next-of-kin of such person; or
(b)if he was not his employer, notify any person known to him to have been the employer of that person at the time of his death or loss.