30 CFR § 77.900-2 - Testing, examination, and maintenance of circuit breakers; record.

---
identifier: "/us/cfr/t30/s77.900-2"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "30 CFR § 77.900-2 - Testing, examination, and maintenance of circuit breakers; record."
title_number: 30
title_name: "Mineral Resources"
section_number: "77.900-2"
section_name: "Testing, examination, and maintenance of circuit breakers; record."
chapter_name: "MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR"
subchapter_number: "O"
subchapter_name: "COAL MINE SAFETY AND HEALTH"
part_number: "77"
part_name: "MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES"
positive_law: false
currency: "2026-03-24"
last_updated: "2026-03-24"
format_version: "1.1.0"
generator: "[email protected]"
authority: "30 U.S.C. 811."
regulatory_source: "36 FR 9364, May 22, 1971, unless otherwise noted."
cfr_part: "77"
---


# 77.900-2 Testing, examination, and maintenance of circuit breakers; record.

The operator shall maintain a written record of each test, examination, repair or adjustment of all circuit breakers protecting low- and medium-voltage circuits serving three-phase alternating current equipment and such record shall be kept in a book approved by the Secretary.