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50 FR 4082, Jan. 29, 1985, unless otherwise noted.
61 FR 36801, July 12, 1996, unless otherwise noted.
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A blasting galvanometer or other instrument designed for testing blasting circuits shall be used to test the following:
(a) In surface operations—
(1) Continuity of each electric detonator in the blasthole prior to stemming and connection to the blasting line;
(2) Resistance of individual series or the resistance of multiple balanced series to be connected in parallel prior to their connection to the blasting line;
(3) Continuity of blasting lines prior to the connection of electric or electronic detonator series; and
(4) Total blasting circuit resistance prior to connection to the power source.
(b) In underground operations—
(1) Continuity of each electric detonator series; and
(2) Continuity of blasting lines prior to the connection of electric or electronic detonators.
[61 FR 36801, July 12, 1996, as amended at 85 FR 2027, Jan. 14, 2020]