HHE Report No. HETA-85-408-1666, Doctors Hiatt, Metcalfe, and Schaad, Denver, Colorado.
NIOSH 1986 Feb:9 pages
Nitrous-oxide (10024972) concentrations in office air were measured directly in September of 1985, and a follow up environmental survey was made in January, 1986 at the Hiatt, Metcalfe, and Schaad dental clinic (SIC-8021), Denver, Colorado. The office manager of the clinic had requested an evaluation of nitrous-oxide exposures during dental procedures. General area samples were taken on the nitrous- oxide administering equipment throughout the dental operatory, in the secretarial work area, and in the breathing zone of the two dental hygienists. Concentrations ranging from 100 to greater than 1000 parts per million (ppm) were found. The average nitrous-oxide concentration was approximately 500 to 600ppm in the breathing zone of the hygienists during the cleaning procedure. Hygienists used 3.5 to 4.5 liters of nitrous-oxide per minute. Nitrous-oxide concentrations in the secretarial areas were 350 to 400ppm while the hygienists were using the gas. NIOSH recommended a 25ppm environmental limit for nitrous-oxide. The author concludes that a health hazard exists from overexposures to nitrous-oxide. A nitrous- oxide scavenging system, lower flow rates, and a better dilution ventilation system are recommended to lower these exposure concentrations.
NIOSH-Author; NIOSH-Health-Hazard-Evaluation; Hazard-Confirmed; HETA-85-408-1666; Region-8; Nitrogen-oxides; Anesthesia; Dentistry; Air-contamination; NIOSH-Technical-Assistance-Report;
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-85-408-1666, 9 pages, 14 references