Section 75.1914 - Maintenance of diesel-powered equipment(a) Diesel-powered equipment shall be maintained in approved and safe condition or removed from service.(b) Maintenance and repairs of approved features and those features required by §§ 75.1909 and 75.1910 on diesel-powered equipment shall be made only by a person qualified under § 75.1915 .(c) The water scrubber system on diesel-powered equipment shall be drained and flushed, by a person who is trained to perform this task, at least once on each shift in which the equipment is operated.(d) The intake air filter on diesel-powered equipment shall be replaced or serviced, by a person who is trained to perform this task, when the intake air pressure drop device so indicates or when the engine manufacturer's maximum allowable air pressure drop level is exceeded.(e) Mobile diesel-powered equipment that is to be used during a shift shall be visually examined by the equipment operator before being placed in operation. Equipment defects affecting safety shall be reported promptly to the mine operator.(f) All diesel-powered equipment shall be examined and tested weekly by a person qualified under § 75.1915 . (1) Examinations and tests shall be conducted in accordance with approved checklists and manufacturers' maintenance manuals.(2) Persons performing weekly examinations and tests of diesel-powered equipment under this paragraph shall make a record when the equipment is not in approved or safe condition. The record shall include the equipment that is not in approved or safe condition, the defect found, and the corrective action taken.(g) Undiluted exhaust emissions of diesel engines in diesel-powered equipment approved under part 36 and heavy-duty nonpermissible diesel-powered equipment as defined in § 75.1908(a) in use in underground coal mines shall be tested and evaluated weekly by a person who is trained to perform this task. The mine operator shall develop and implement written standard operating procedures for such testing and evaluation that specify the following: (1) The method of achieving a repeatable loaded engine operating condition for each type of equipment;(2) Sampling and analytical methods (including calibration of instrumentation) that are capable of accurately detecting carbon monoxide in the expected concentrations;(3) The method of evaluation and interpretation of the results;(4) The concentration or changes in concentration of carbon monoxide that will indicate a change in engine performance. Carbon monoxide concentration shall not exceed 2500 parts per million; and(5) The maintenance of records necessary to track engine performance.(h)Recordkeeping. Records required by paragraphs (f)(2) and (g)(5) shall be- (1) Recorded in a secure book that is not susceptible to alteration, or recorded electronically in a computer system that is secure and not susceptible to alteration; and(2) Retained at a surface location at the mine for at least 1 year and made available for inspection by an authorized representative of the Secretary and by miners' representatives.(i) Diesel-powered equipment must be maintained in accordance with this part as of November 25, 1997.