The NIOSH B reader certification program. An update report.

Physicians trained in the use of the International Labour Office system for classification of radiographs of pneumoconioses who pass a competence test administered by the National Institute for Occupational Safety and Health are designated as B readers. The current certification and recertification examinations for qualification under the NIOSH B reader program are described. Details of the rationale and format of each examination are given, and information on candidates' scores provided for the years 1987-1990.