(a) Respirators described in subparts H through L of this part shall be classified, where applicable, as approved for use during the following prescribed service times:
- (1) Four hours;
- (2) Three hours;
- (3) Two hours;
- (4) One hour;
- (5) Forty-five minutes;
- (6) Thirty minutes;
- (7) Fifteen minutes;
- (8) Ten minutes;
- (9) Five minutes; or
- (10) Three minutes.
- (b) Other service times may be prescribed by the Institute.