Effect of relative humidity on the determination of formaldehyde with the NIOSH 3500 method (chromatropic acid method)

Abstract

The relative humidity of a formaldehyde test atmosphere was found to be a factor in formaldehyde determination using the chromatropic acid (CTA) method; also known as the NIOSH 3500 method.Formaldehyde recovery efficiencies of 100% were obtained when the relative humidity was below 0.1% at temperatures across the range 22–27 °C. Relative humidity levels of 50% and then >95% gave reduced efficiencies of 66 and 36%, respectively, across the temperature range 22–27 °C. Multiple linear regression yielded a correction algorithm for the CTA method that accounted for the influence of water at all the concentrations, masses and relative humidities studied:

References

1. National Institution of Occupational Safety and Health, NIOSH, Manual of nalytical Methods, Method 3500, National Institution of Occupational Safety and Health, Washington, DC, 1989.
2. T. E. Graelel, in Chemical Compounds in the Atmosphere, Academic Press, London, 1978, p. 158.
3. P. Carlier, H. Hannachi and G. Mouvier, Atmos. Environ., 1986, 20, 2079.
4. R. J. Fielder, Toxicity Review 2, Formaldehyde, Health and Safety Executive, HMSO, London, 1981.
5. E. N. Light, Formaldehyde, Analytical Chemistry and Toxicology, ed. Turoski, V., Advances in Chemistry Series 210, American Chemical Society, Washington, DC, 1985.
6. Health and Safety Executive, HSE EH40/91 Occupational Exposure Limits 1991, Health and Safety Executive, London, 1991.
7. E. J. Bardana and A. Montanaro, Resp. Cut. Innum. Annul. Allergy, 1991, 66, 441.
8. E. Goelen, M. Lambrechts and F. Geyskens, Analyst, 1997, 122, 411.
9. C. L. P. Thomas, C. D. McGill and R. Towill, Analyst, 1997, 122, 1471.
10. P. W. West and B. Sen, Z. Anal. Chem., 1956, 153, 177.
11. A. P. Altshuller, D. L. Miller and S. F. Sleva, Anal. Chem., 1961, 33, 621.
12. F. Meunier, M. Sc. Dissertation, 1996.
13. F. J. Lovas and C. L. Lugez, J. Mol. Spectrosc., 1996, 179, 320.
14. National Institution of Occupational Safety and Health, NIOSH, Manual of Analytical Methods, Method 2541, National Institution of Occupational Safety and Health, Washington, DC, 1989.
15. J. Levin, K. Andersson, R. Lindahl and C. Nilsson, Anal. Chem., 1985, 57, 1532.
16. E. Grosjean and D. Grosjean, J. Am. Chem. Soc., 1996, 30, 859.
17. C. L. P. Thomas and J. F. Alder, Anal. Chim. Acta, 1993, 27, 179.