30 CFR 27.22 : Mineral Resources (§ 1.1 To Parts 1291-1299) — (§ 1.1 To Parts 105-199) — Mine Safety And Health Administration, Department Of Labor (§ 1.1 To Parts 105-199) — Testing, Evaluation, And Approval Of Mining Products (§ 5.10 To § 36.50) — Methane-Monitoring Systems (§ 27.1 To § 27.41) — Construction And Design Requirements (§ 27.20 To § 27.24) — Methane detector component.

(a) A methane detector component shall be suitably constructed for incorporation in or with permissible and approved equipment that is operated in gassy mines and tunnels.

(b) A methane detector shall include:

(1) A method of continuous sampling of the atmosphere in which it functions.

(2) A method for actuating a warning device which shall function automatically at a methane content of the mine atmosphere between 1.0 to 1.5 volume percent. The warning device shall also function automatically at all higher concentrations of methane in the mine atmosphere.

(3) A method for actuating a power-shutoff component, which shall function automatically when the methane content of the mine atmosphere is 2.0 volume percent and at all higher concentrations of methane.

(4) A suitable filter on the sampling intake to prevent dust and moisture from entering and interfering with normal operation.

(c) A methane detector may provide means for sampling at more than one point; provided, the methane detector shall separately detect the methane in the atmosphere at each sampling point with, in MSHA's opinion, sufficient frequency.