30 CFR § 27.41 - Test to determine resistance to moisture.

---
identifier: "/us/cfr/t30/s27.41"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "30 CFR § 27.41 - Test to determine resistance to moisture."
title_number: 30
title_name: "Mineral Resources"
section_number: "27.41"
section_name: "Test to determine resistance to moisture."
chapter_name: "MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR"
subchapter_number: "B"
subchapter_name: "TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS"
part_number: "27"
part_name: "METHANE-MONITORING SYSTEMS"
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. 957, 961."
regulatory_source: "31 FR 10607, Aug. 9, 1966, unless otherwise noted."
cfr_part: "27"
---


# 27.41 Test to determine resistance to moisture.

Components, subassemblies, or assemblies, the normal functioning of which might be affected by moisture, shall be tested in atmospheres of high relative humidity (80 percent or more at 65°-75 °F.) for continuous operating and idle periods of 4 hours each. The component or subassembly or assembly shall function normally after being subjected to those tests.