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Subchapter 17. Mine Safety Orders
Article 32. Gases in Mines
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§7104. Tests for Gases.

(a) Tests for flammable gases shall be made with a permissible methane detector or by chemical analysis.

Note: To be of most value in active mines, it is necessary that the percent of gas present be quickly and accurately determined. Because of the time required to collect and analyze air samples, and the relative insensitivity of the flame safety lamp, it is strongly recommended that a permissible methane detector be used for testing.

(b) Tests for any gas other than flammable gas shall be made by chemical analysis or by use of a testing device designed to detect the particular gas for which the test is being made, and to measure its concentration.

(c) When the air in any part of a mine is known to contain or is suspected of containing dangerous or explosive gas, it shall be tested by means acceptable to the Division of Industrial Safety before employees are allowed to work therein. These tests shall be made by an individual who has been certified by the Division to make them.

Every person requesting certification as a gas tester shall submit a completed application form to the Division. Upon submission of an application for certification as a gas tester, the Division shall collect the amount of $15.00 for examination fee which is non-refundable. Renewal fees are $5.00 annually.

Note: See Section 6967 (b) for Labor Code excerpts.

Note: Authority cited: Section 142.3, Labor Code. Reference: Section 142.3, Labor Code


1. Repealer of subsection (c) and new subsection (c) filed 8-1-74; effective thirtieth day thereafter (Register 74, No. 31).

2. Change without regulatory effect amending subsection (c) and Note filed 3-17-2011 pursuant to section 100, title 1, California Code of Regulations (Register 2011, No. 11).

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