(a) Operators of mines are required to employ one or more certified fire bosses and to have a preshift examination made. The duties of the fire boss are to examine for dangerous conditions all manways, slopes, and entries used by men in traveling to and from work and to examine for gas and other dangerous conditions all working places, adjoining abandoned places, and accessible pillar falls for accumulation of gas. The fire boss will ascertain that the air is traveling in its proper course and that all ventilation appliances are in good condition and working effectively. The fire boss will indicate his examination of working and abandoned places, pillar falls, and ventilating appliances by marking his initial and the date conspicuously in or on such places.

(b) Whenever gas is detected or danger exists to men entering any place, the fire boss shall leave at each entrance to the place a conspicuous DANGER sign.

(c) Examination of the first working place in mines shall take place not more than three hours before the men are permitted to enter the mine or to pass a designated station underground.

(d) The fire boss shall meet the oncoming shift at the point or station designated and inform each man as to the condition of his working place or the place in which his machine is parked. Each face boss and direct supervisor shall be informed by the fire boss as to the condition of all places under his direction or control. When man trip schedules or other compelling factors make it impractical for the fire boss to check each man, the fire boss will furnish to responsible supervisors written signed reports of his inspection and these supervisors will be responsible for informing each man as to the condition of his working place.

(e) In multiple shift operations, certified supervisors may be used to make the fire boss examination for the next or succeeding shift. Responsible supervisors of the next or succeeding shift may be used to inform each man as to the condition of his working place and may be held responsible, provided the certified supervisors who made the examination furnish a written, signed report as to condition of each working place.

(f) The fire boss shall record the results of his inspection in ink or indelible pencil in a book kept on the surface for that purpose. Similar records may be kept at designated stations or offices underground. This book shall be countersigned daily by the mine foreman. The mine superintendent or his assistant shall also read and countersign the reports.

(g) Idle and abandoned parts of any mine shall be examined by a certified person immediately before employees are permitted to enter or work in such areas.

(h) Examination for gas and other dangerous conditions shall be made by a certified official or approved competent person before taking loading or cutting machines in by the open breakthrough nearest the face or before applying power to machinery that remains at or near the face at not more than 20-minute intervals during cutting, drilling, or mechanical loading, before drilling with electric drills, before blasting, after blasting, and before other work is resumed and at such other times as may be necessary or designated by the operator or mine inspector for adequate safety.

(i) All persons underground shall use only permissible electric cap lamps for portable illumination that is worn on the person. This does not preclude the use of other types of permissible electric lamps, permissible flashlights, permissible safety lamps, or any other portable illumination classed as permissible.

(j) Open cap lights and smoking and smokers' articles, including matches, are prohibited in underground mines.