Quality of spirometry in silica, wood and foundry workers in GB

Background: Spirometry is commonly used in GB for health surveillance in workers exposed to vapours, dusts, gases and fumes. The quality of workplace lung function testing is variable, with some occupational health providers only performing a single trial. Aims: To examine the quality of research lung function testing in different workplaces and the potential impact of not performing reproducible tests as per the ATS/ERS standards. Methods: Spirometry performed in workplaces as part of a five-year longitudinal study was assessed as per the ATS/ERS standards. The potential effect of performing fewer than three trials was calculated. Results: During initial baseline data collection a total of 937 participants were surveyed from four industries (189 brick, 128 stone, 351 foundry, 269 wood). 932/937 participants performed spirometry. Using the ATS/ERS standards, 91% (849/932) of all participants met the criteria for both FEV 1 and FVC. Variability within industry ranged from 95% reproducibility (brick) to 89% reproducibility (wood). All five technologists met the ATS/ERS criteria for 88-100% of all tests they performed. Participants meeting standards had a mean of four trials (minimum of 2, maximum of 15). Assessment of the silica and foundry data showed that relying solely on the first expiratory manoeuvre led to an average under estimate in FEV 1 of 120mls and on the first and second manoeuvre an under estimate of 40mls. Conclusions: Reproducible spirometry is achievable in a workplace environment in research studies. This study has highlighted the importance of performing workplace spirometry to ATS/ERS standards for reproducibility.