Formation and emission of hydrogen chloride in indoor air

Kathryn E.R. Dawe, Teles C. Furlani, Shawn F. Kowal, Tara F. Kahan, Trevor C. VandenBoer, Cora J. Young

Research output: Contribution to journalArticlepeer-review

29 Scopus citations


To improve our understanding of chlorine chemistry indoors, reactive chlorine species such as hydrogen chloride (HCl) must be analyzed using fast time-response measurement techniques. Although well studied outdoors, sources of HCl indoors are unknown. In this study, mixing ratios of gaseous HCl were measured at 0.5 Hz in the indoor environment using a cavity ring-down spectroscopy (CRDS) instrument. The CRDS measurement rate provides a major advance in observational capability compared to other established techniques. Measurements of HCl were performed during three types of household activities: (a) floor exposure to bleach, (b) chlorinated and nonchlorinated detergent use in household dishwashers, and (c) cooking events. Surface application of bleach resulted in a reproducible increase of 0.1 ppbv in the affected room. Emissions of HCl from automated dishwashers were observed only when chlorinated detergents were used, with additional HCl emitted during the drying cycle. Increased mixing ratios of HCl were also observed during meal preparation on an electric element stovetop. These observations of HCl derived from household activities indicate either direct emission or secondary production of HCl via chlorine atoms is possible. Calculations of photolysis rate constants of chlorine atom precursors provide evidence that photolysis may contribute to indoor HCl levels.

Original languageEnglish (US)
Pages (from-to)70-78
Number of pages9
JournalIndoor Air
Issue number1
StatePublished - Jan 2019


  • bleach
  • cavity ring-down spectroscopy
  • cooking
  • hydrochloric acid
  • reactive chlorine
  • real-time measurements

ASJC Scopus subject areas

  • Environmental Engineering
  • Building and Construction
  • Public Health, Environmental and Occupational Health


Dive into the research topics of 'Formation and emission of hydrogen chloride in indoor air'. Together they form a unique fingerprint.

Cite this