30 CFR § 955.11 - General requirements.
To qualify for an OSM blaster certificate, a person shall:
(a) Be at least 20 years old prior to submitting an application, and at least 21 years old prior to the grant of a certificate;
(b) In the 3 years prior to submitting an application have been qualified and worked as a blaster or the equivalent, or have worked under the direction of a blaster or the equivalent, for the following cumulative length of time:
(1) Certificate issuance - 2 years; or
(2) Certificate renewal or reissuance - 1 year;
(c) For certificate issuance or reissuance, have received on-the-job training, completed a training course, and obtained satisfactory evidence of having completed training, as provided in § 955.12;
(d) Be competent, possess practical knowledge of blasting techniques, understand the hazards involved in the use of explosives, and exhibit a pattern of conduct consistent with the acceptance of responsibility for blasting operations;
(f) For certificate issuance or reissuance, pass a written examination as provided in § 955.14;
(h) Not be subject to suspension, revocation or other action under § 955.17.