the National Institute for Occupational Safety and Health (NIOSH) received a request from the United Cement, Lime, Gypsum and Allied Workers Union Local 421 in Tulsa to examine possible health hazards arising from burning "high-sulfur" coal at the Martin-Marietta Cement Plant in Tulsa, Oklahoma. Of specific concern were exposures to sulfur dioxide (S02), carbon monoxide (CO), carbon dioxide (CO2), and hydrogen Sulfide (H2S). Two rounds of a mail questionnaire were sent out prior to a hazard survey October 22-23, 1981. During the survey employees were questioned about medical complaints and area samples were collected for sulfur dioxide, sulfates, sulfites, carbon monoxide, nitrogen dioxide, and hydrogen sulfide. Sulfur dioxide is being released into the plant environment from kiln exhausts escaping from baghouses. Workers have been intermittently reporting irritant symptoms compatible with sulfur dioxide exposure. Concentratrions of 502 measured in the kiln baghouses, kiln feed building, and on top of the raw silos were at 1.2, 1.8, and 1.7 ppm respectively. These levels are capable of causing irritation and acute bronchial airway changes, Levels of carbon monoxide and nitrogen dioxide were detected in the mobile equipment maintenance garage, but these measurements were below concentrations known to cause toxic effects.