HHE determination report no. HHE-79-5-564, Children's Hospital Dental Department, Cincinnati, Ohio.
Cincinnati, OH: U.S. Department of Health, Education, and Welfare, Public Health Service, Centers for Disease Control, National Institute for Occupational Safety and Health, HHE 79-5-564, 1979 Feb; :1-11
Breathing zone (BZ) and general area (GA) samples for nitrous oxide (10024972) (N2O) were collected to determine exposure concentrations to dental residents and assistants at the Children's Hospital (SIC- 8081) Dental Department in Cincinnati, Ohio on December 14 and 15, 1978. A dental resident requested the evaluation for approximately 25 people. Concentrations of N2O ranged from 40 to 3500 parts per million (ppm) during application, which occasionally exceeded the NIOSH recommended concentrations of 50ppm. Five of 36 measurements of N2O after application were below 50ppm. Highest concentrations occurred in the BZ during application with an N2O to oxygen ratio greater than 2:4 liters per minute. Operatories using cracked or loose N2O breathing hoses had concentrations exceeding 3000ppm. The investigator concludes that sources of N2O included the anesthesia machine, nasal mask, patient's mouth, and operatories from adjacent rooms. The investigator recommends that scavenging equipment be used; venting suction mechanism outside the building be maintained properly; conversation with the patient during N2O administration be minimized; anesthesia equipment be inspected and tested monthly; an air monitoring program be designed and implemented; and where acceptable concentrations of N2O are not achieved, use of an air sweep to remove N2O be considered.
NIOSH-Author; HHE-79-5-564; NIOSH-Health-Hazard-Evaluation; Hazard-Unconfirmed; Region-5; Anesthetics; Irritant-gases; Air-monitoring; Environmental-engineering; Respiratory-equipment; Occupational-exposure;
Author Keywords: dental clinic; waste anesthetic gases; nitrous oxide; scavenging techniques
Field Studies; Health Hazard Evaluation
NTIS Accession No.
National Institute for Occupational Safety and Health