42 CFR §37.53

1. (a)All chest radiographs which are first classified by an A or B Reader will be submitted by NIOSH to a B Reader qualified pursuant to § 37.52.
   1. (1)If there is agreement between the two classifications, as described in paragraph (b) of this section, the result will be considered final and reported to MSHA for transmittal to the miner.
   2. (2)When agreement is lacking, NIOSH must obtain a third classification from the panel of B Readers.
      1. (i)If any two of the three classifications demonstrate agreement, the result must be considered the final determination.
      2. (ii)If agreement is lacking among the three classifications, NIOSH will obtain independent classifications from two additional B Readers selected from the panel, and the final determination will be the median category derived from the total of five classifications.
2. (b)Two classifications are considered to be in agreement when:
   1. (1)They are derived from complete classifications recorded using approved paper or electronic versions of the Chest Radiograph Classification Form (CDC/NIOSH 2.8) and received by NIOSH; and
   2. (2)Both find either stage A, B, or C complicated pneumoconiosis; or,
   3. (3)For simple pneumoconiosis, are both in the same major category or are within one minor category (ILO Classification 12-point scale) of each other (subject to the exception in paragraph (b)(3)(ii) of this section).
      1. (i)The higher of the two classifications must be reported.
      2. (ii)The only exception to the one minor category principle is a reading sequence of 0/1, 1/0 or 1/0, 0/1, which are not considered agreement.