The he ChemSafety Nitrous oxide Monitor is a passive sampling device used to measure workplace exposure to nitrous oxide and indoor air quality.
The air sample is collected when it diffuses through a specially prepared membrane and is collected inside the device.
After the device is used, it is returned to the laboratory for analysis. All analysis are done by methods validated by the US OSHA and NIOSH.
The National Institute of Occupational Safety and Health (NIOSH) recommends an exposure limit of 25 ppm while the gas is in use. This level is based on what can be achieved in practice in a dental operatory. If there is an effective scavenger, no leaks, and the patient is cooperative, it is not directly related to long term health effects. The American Conference of Government Industrial Hygienists (ACGIH) has examined toxicological data and concludes that there are no significant long-term health effects if the average concentration over an 8-hour day is below 50 ppm.
