Section 70.204 - Approved sampling devices; maintenance and calibration(a) Approved sampling devices shall be maintained as approved under part 74 of this title and calibrated in accordance with MSHA Informational Report IR 1240 (1996) "Calibration and Maintenance Procedures for Coal Mine Respirable Dust Samplers" or in accordance with the manufacturer's recommendations, if using a CPDM. Only persons certified in maintenance and calibration can perform maintenance work on the CPDM or the pump unit of the CMDPSU.(b) Sampling devices shall be calibrated at the flowrate of 2.0 liters of air per minute (L/min) if using a CMDPSU; at 2.2 L/min if using a CPDM; or at a different flowrate recommended by the manufacturer, before they are put into service and, thereafter, at time intervals recommended by the manufacturer or prescribed by the Secretary or Secretary of HHS.(c) If using a CMDPSU, each sampling device shall be examined and tested by a person certified in sampling or in maintenance and calibration within 3 hours before the start of the shift on which the approved sampling devices will be used to collect respirable dust samples. This is to assure that the sampling devices are clean and in proper working condition. This examination and testing shall include the following: (1) Examination of all components of the cyclone assembly to assure that they are clean and free of dust and dirt. This includes examining the interior of the connector barrel (located between the cassette assembly and vortex finder), vortex finder, cyclone body, and grit pot;(2) Examination of the inner surface of the cyclone body to assure that it is free of scoring or scratch marks on the inner surface of the cyclone where the air flow is directed by the vortex finder into the cyclone body;(3) Examination of the external hose connecting the pump unit to the sampling head assembly to assure that it is clean and free of leaks; and(4) Examination of the clamping and positioning of the cyclone body, vortex finder, and cassette to assure that they are rigid, in alignment, firmly in contact, and airtight.(5) Testing the voltage of each battery while under actual load to assure the battery is fully charged. This requires that a fully assembled and examined sampling head assembly be attached to the pump inlet with the pump unit running when the voltage check is made. The voltage for the batteries used in the CMDPSU shall not be lower than the product of the number of cells in the battery multiplied by the manufacturer's nominal voltage per cell value.(d) If using a CPDM, the certified person in sampling or in maintenance and calibration shall: (1) Follow the pre-operational examinations, testing, and set-up procedures, and perform necessary external maintenance recommended by the manufacturer to assure the operational readiness of each CPDM within 3 hours before the start of the shift on which the sampling devices will be used to collect respirable dust samples; and(2) Perform other required scheduled examinations and maintenance procedures recommended by the manufacturer.(e) You must proceed in accordance with "Calibration and Maintenance Procedures for Coal Mine Respirable Dust Samplers," MSHA Informational Report IR 1240 (1996), referenced in paragraph (a) of this section. The Director of the Federal Register approves this incorporation by reference in accordance with 5 U.S.C. 552(a) and 1 CFR part 51 . You may obtain a copy from the MSHA Web site at http://www.msha.gov and you may inspect or obtain a copy at MSHA, Coal Mine Safety and Health, 201 12th Street South, Arlington, VA 22202-5452; 202-693-9500; and at each MSHA Coal Mine Safety and Health District Office, or at the National Archives and Records Administration (NARA). For information on the availability of this material at NARA, call 202-741-6030, or go to: http://www.archives.gov/federal_register/code_of_federal_regulations/ibr_locations.html. 79 FR 24974 , May 1, 2014, as amended at 80 FR 52989 , Sept. 2, 2015