30 CFR § 75.800-4
Testing, examination and maintenance of circuit breakers; record.
(a) Recordkeeping. The operator shall make a record of each test,
examination, repair, or adjustment of all circuit breakers protecting
high-voltage circuits which enter any underground area of the mine.
(b) Record security. These records shall be made in a secure book
that is not susceptible to alteration or electronically in a computer
system so as to be secure and not susceptible to alteration.
(c) Retention and access. These records shall be retained at a
surface location at the mine for at least one year and shall be made
available to authorized representatives of the Secretary, the
representative of miners, and other interested persons.
[35 FR 17890, Nov. 20, 1970, as amended at 47 FR 14706, Apr. 6, 1982; 60 FR
33719, June 29, 1995]