A Performance Evaluation of Two Portable Infrared Gas Analyzers for the Measurement of Nitrous Oxide Under Laboratory Conditions
Abstract
Objective: The objective of this study was to investigate the level of agreement between a Bacharach PGM-IR N2O 3015-4787 Monitor, Viasensor G200 N2O Analyzer, and a Gasmet DX4040 reference instrument across a discrete range of nitrous oxide (N2O) concentrations, at 21 deg C, and at 22 percent and 80 percent relative humidity (RH) levels. Agreement acceptable for the study would be +-25 percent of the true concentration as monitored by the Gasmet. The study sought to determine if there was a statistically significant difference between the mean measurements of the Bacharach, Viasensor, and the reference instrument. Information regarding the infrared gas analyzer (IGA) with the best agreement with the reference instruments nitrous oxide measurements would be offered to the IHS to augment their consideration of a replacement instrument. Methods: Controlled and homogenous nitrous oxide gas atmospheres were generated with a dynamic cylinder dilution system where sampling occurred over an evaluation range of 1 to 500 ppm. Three repeated trials occurred. Each trial consisted of four replicate samples at 21 deg C, and at relative humidity levels of 22 percent and 80 percent. Four two-way analysis of variance (ANOVA) analyses were performed to identify statistically significant differences between the mean measurements of each investigated IGA when compared to the mean measurements of the reference instrument. The level of agreement between the IGAs with the reference instrument was evaluated to determine if it met the 25 percent criteria set forth by the National Institute for Occupational Safety and Health (NIOSH). Twelve Bland-Altman analyses were used to investigate the specific level of agreement between each investigated IGA and the reference instrument. Results: Two-way ANOVA analyses revealed that the mean measurements of both tested instruments were significantly different than the mean measurements of the reference instrument (p less than.00005).
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 04, 2021
- Accession Number
- AD1186123
Entities
People
- Brandon Parker
Organizations
- Uniformed Services University of the Health Sciences