30 CFR § 23.6 - General requirements for approval.

---
identifier: "/us/cfr/t30/s23.6"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "30 CFR § 23.6 - General requirements for approval."
title_number: 30
title_name: "Mineral Resources"
section_number: "23.6"
section_name: "General requirements for approval."
chapter_name: "MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR"
subchapter_number: "B"
subchapter_name: "TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS"
part_number: "23"
part_name: "TELEPHONES AND SIGNALING DEVICES"
positive_law: false
currency: "2026-04-05"
last_updated: "2026-04-05"
format_version: "1.1.0"
generator: "[email protected]"
authority: "30 U.S.C. 957, 961."
regulatory_source: "Schedule 9B, 4 FR 1555, Apr. 11, 1939, unless otherwise noted."
cfr_part: "23"
---


# 23.6 General requirements for approval.

Telephones and signaling devices shall be durable in construction, practical in operation, and suitable for conditions of underground service. They shall offer no probable explosion hazard under normal operation if use in gassy or dusty mine atmospheres.