30 CFR § 7.69 - Approval marking.

---
identifier: "/us/cfr/t30/s7.69"
source: "ecfr"
legal_status: "authoritative_unofficial"
title: "30 CFR § 7.69 - Approval marking."
title_number: 30
title_name: "Mineral Resources"
section_number: "7.69"
section_name: "Approval marking."
chapter_name: "MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR"
subchapter_number: "B"
subchapter_name: "TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS"
part_number: "7"
part_name: "TESTING BY APPLICANT OR THIRD PARTY"
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."
regulatory_source: "53 FR 23500, June 22, 1988, unless otherwise noted."
cfr_part: "7"
---


# 7.69 Approval marking.

Each approved blasting unit shall be identified as permissible by a legible and permanent marking securely attached, stamped, or molded to the outside of the unit. This marking shall include the following:

(a) The assigned MSHA approval number.

(b) The maximum blasting circuit resistance.

(c) A warning that the unit's components must not be disassembled or removed.

(d) The replacement battery types if the unit has replaceable batteries.

(e) A warning placed next to the charging connector that the battery only be charged in a fresh air location if rechargeable batteries are used.

(f) A warning that the unit is compatible only with detonators that will—

(1) Fire when an average of 1.5 amperes is applied for 5 milliseconds;

(2) Not misfire when up to an average 100 amperes is applied for 10 milliseconds; and

(3) Not fire when a current of 250 milliamperes or less is applied.