Continuous Measurement of Peak Hydrogen Fluoride Exposures in Aluminum Smelter Potrooms: Instrument Development and In-Plant Evaluation

Abstract

The aluminum smelting process continuously evolves both sulfur dioxide (SO ₂ ) and hydrogen fluoride (HF) gases. The vast majority of these evolved gases are captured by local exhaust ventilation systems and transported to fume treatment centers. Any gas escaping the ventilation systems could create the potential for workplace exposures. Currently, there are no commercially available sensors that are capable of selectively measuring peak concentrations (< 10 sec) of HF in the presence of SO ₂ . This measurement capability is critical for facilitating a better understanding of the etiology of respiratory health effects. This article presents the development and in-plant testing of a portable, tunable diode-based HF sensor that shows equivalent or improved performance relative to NIOSH Method 7902 and is capable of measuring short-term personal peak HF exposure potentials in operating aluminum smelters.

Keywords:

• exposure
• hydrogen fluoride
• HF
• personal monitor
• SO₂
• sulfur dioxide

ACKNOWLEDGMENTS

The authors would like to thank the Occupational Health and Hygiene subgroup of the International Aluminum Institute (IAI) for funding this project. The authors would also like to thank Mike McGarvey for assistance with the NIOSH cassette testing, and Linda Maillet for facilitating the in-plant evaluation of the personal HF monitor.