Is one obliged to have one´s lifejacket serviced?

If we had our say, yes. If you had the final say, that ought to be the case, too. If we go by legislation, the law is keeping out of it in this case. But if there has been an accident which was due to a lifejacket not having been serviced, then the law becomes involved again and makes it clear to the person who has no obligation to take the lifejacket for a service that it is his duty to service the lifejacket.