HHE Report No. HETA-92-0263-2424, Boise Cascade, Timber and Wood Products Division, Kettle Falls, Washington.
NIOSH 1994 May:34 pages
In response to a confidential request from employees at Boise Cascade, Timber and Wood Products Division (SIC-2436), Kettle Falls, Washington, an evaluation was conducted of exposure to fly ash and smoke emissions from veneer dryers at the facility and around two fluidized bed combustors located adjacent to the site. A case of manganese (7439965) poisoning had been reported in a worker. Bulk samples of residue collected on the inside and outside surfaces of veneer dryers indicated manganese was present in concentrations ranging from 1,900 to 6,600 micrograms per gram (microg/g). Fly ash collected near the fluidized bed combustors ranged in manganese concentration from 3,300 to 5,200microg/g. One sample of a kaolin clay based refractory sand used in a fluidized bed combustor contained 30,000microg/g manganese. Twelve personal breathing zone exposures to respirable dust ranged from 0.09 to 6.7mg/m3. Respirable silica (14808607) concentrations exceeded the NIOSH recommended exposure limit of 0.05mg/m3. The source of manganese was from manganese containing wood ash generated by the combustion of hogging fuel. Bulk samples of sawdust and hogging fuel ranged from 46 parts per million (ppm) for sawdust from peeled timber to 310ppm for predominantly bark sample. The authors conclude that a potential occupational health hazard existed for workers exposed to manganese and silica. The authors recommend specific measures to improve working conditions and health and safety practices at this facility.
NIOSH-Author; NIOSH-Health-Hazard-Evaluation; NIOSH-Technical-Assistance-Report; HETA-92-0263-2424; Hazard-Confirmed; Region-10; Combustion-products; Sawmill-workers; Occupational-exposure; Mineral-dusts; Fly-ash;
Hazard Evaluation and Technical Assistance;
NTIS Accession No.
Hazard Evaluations and Technical Assistance Branch, NIOSH, U.S. Department of Health and Human Services, Cincinnati, Ohio, Report No. HETA-92-0263-2424, 34 pages, 28 references