Pennsylvania Statutes Title 52 P.S. Mines and Mining § 690-320. Underground illumination

(a) Sockets.--In all mines, the sockets of fixed electric lamps shall be of so-called weatherproof type, the exterior of which shall be entirely nonmetallic. Flexible lamp cord connections are prohibited except for portable lamps as provided under subsection (c).

(b) Lamps.--Electric lamps shall be placed so they cannot come in contact with combustible material.

(c) Portable electric lamps.--Portable electric lamps, other than battery lamps, shall not be used in connection with the repair and inspection of machines and equipment in face areas. When used elsewhere, they shall be protected by a heavy wire cage completely enclosing both lamp and socket and shall be provided with a handle to which both cage and socket are firmly attached and through which the lead-in wires are carried.

(d) Electric lamp enclosure.--Electric lamps, when used in face areas of any mine, shall be installed in explosion-proof enclosures.

(e) Electric lamp replacement.--Electric lamps shall be replaced by a competent individual. In face areas, a qualified individual shall be utilized after an examination for gas has been made with an approved gas detection device.

(f) Underground photography.--Underground photography using flash bulbs or other sources of artificial illumination shall be prohibited unless immediately preceded by an examination for gas by a mine foreman, assistant mine foreman or mine examiner, and the place is found safe.