30 CFR § 57.6161
Auxiliary facilities.
(a) Auxiliary facilities used to store explosive material near work places
shall be wooden, box-type containers equipped with covers or doors, or
facilities constructed or mined-out to provide equivalent impact resistance
and confinement.
(b) The auxiliary facilities shall be--
(1) Constructed of nonsparking material on the inside when used for the
storage of explosives;
(2) Kept clean, suitably dry, and orderly;
(3) Kept in repair;
(4) Located out of the line of blasts so they will not be subjected to
damaging shock or flyrock;
(5) Identified with warning signs or coded to indicate the contents with
markings visible from any approach;
(6) Located at least 15 feet from all haulageways and electrical equipment, or
placed entirely within a mined-out recess in the rib used exclusively for
explosive material;
(7) Filled with no more than a one-week supply of explosive material;
(8) Separated by at least 25 feet from other facilities used to store
detonators; and
(9) Kept securely locked unless all access to the mine is either locked or
attended.
[58 FR 69596, Dec. 30, 1993]