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Subchapter 17. Mine Safety Orders
Article 46. Dangerous Excavations at Underground Mines
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§7178. Dangerous Excavations.

(a) (20-20) Access to unattended mine openings shall be restricted by gates or doors, or the openings shall be fenced and posted.

(b) (20-21) Every dangerous surface excavation in which work has been discontinued, including any tunnel, mine shaft, pit, well, septic tank, cesspool, or other abandoned excavation, shall be securely covered over, fenced, or otherwise effectively guarded and appropriate danger notices shall be posted.

(c) (20-21) All dangerous inactive or abandoned underground mine workings shall be securely covered over, fenced, or otherwise effectively guarded to prevent entrance of employees into such workings.

Where the method of guarding does not positively prevent entrance into the dangerous workings, such entrance shall be plainly marked with legible signs warning unauthorized employees to keep out.

(d) (20-31) In areas where dangerous accumulations of water, gas, mud, or fire atmosphere could be encountered, employees shall be removed to safe places before blasting.

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


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

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