MSHA - Code of Federal Regulations - 30 CFR 56.6300
30 CFR § 56.6300
Control of blasting operations.
(a) Only persons trained and experienced in the handling and use of explosive
material shall direct blasting operations and related activities.
(b) Trainees and inexperienced persons shall work only in the immediate
presence of persons trained and experienced in the handling and use of
[58 FR 69596, Dec. 30, 1993]