Environmental monitoring of nitrous oxide during dental anaesthesia.

Abstract

The study was carried out to see if levels of nitrous oxide in dental theatres and community dental clinics were being controlled in accordance with the Control of Substances Hazardous to Health Regulations. A multi-centre study looked at exposure levels in a dental teaching hospital and two community dental clinics in the South Wales area between 1997 and 1998. A MIRAN infra-red spectrophotometer was used to measure static levels of nitrous oxide during general anaesthesia and conscious sedation. NIOSH method 6600 was used to collect personal samples of the individual administering the anaesthetic. The results showed compliance with the regulations when averaged out over an 8 hour time weighted average. However, over short periods of time peak concentrations of up to 1190 ppm were observed through static sampling, and up to 734 ppm through personal sampling. The results highlighted the need to provide adequate control measures such as anaesthetic gas scavenging, to reduce occupational exposure to dental staff in dental operating theatres and community dental clinics, therefore providing a safe working environment.