Ozone removal by occupants in a classroom

• Published in: Atmospheric environment (1994) Vol. 81; no. 1; pp. 11 - 17
• Main Authors: Fischer, Andreas, Ljungström, Evert, Langer, Sarka
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.12.2013; Elsevier
• Subjects: 4-Oxopentanal; adsorption; Air. Soil. Water. Waste. Feeding; allergic reaction; Annan kemi; Applied sciences; atmospheric chemistry; atmospheric deposition; Atmospheric pollution; Biological and medical sciences; body surface; bronchospasm; building material; circadian rhythm; concentration (composition); concentration (parameters); Deposition; Deposition velocities; Deposition velocity; Environment. Living conditions; Environmental Sciences; Exact sciences and technology; furniture; human; humans; indoor air; Indoor environment; Indoor pollution and occupational exposure; limit of detection; Medical sciences; Miljövetenskap; oils; organic compound; Other Chemistry Topics; oxidation; Ozone; Ozone Deposition velocity; physical activity; pollutant removal; Pollution; priority journal; Public health. Hygiene; Public health. Hygiene-occupational medicine; Rate constants; School; Squalene; teachers; Teaching; trigeminal nerve; velocity; volatile organic compound; waste component removal; Squalene; Ozone; 4-Oxopentanal; School; Deposition velocity; Indoor environment; Human; Photochemical oxidants; Surface reaction; Pollutant behavior; Reaction product; Pollution prevention; Sebum; Volatile organic compound; Deposition rate; Aldehyde; Ketone; Indoor pollution; Skin; Child; Organic compounds; Anthropogenic factor; Heterogeneous reaction
• ISSN: 1352-2310; 1873-2844; 1873-2844
• DOI: 10.1016/j.atmosenv.2013.08.054

Ozone concentrations were measured in a classroom with and without occupants, with the purpose to quantify effects on indoor O3 concentrations. The teacher and 24 11-year old pupils each removed O3 at a rate, first order in O3, corresponding to a rate constant of (2.5 ± 0.6) × 10−5 s−1 in the present locality and to a deposition velocity of 0.45 cm s−1. The O3-removal caused by the occupants was approximately 2.6 times larger than that of the available surfaces belonging to the classroom and its furniture. Observation of 6-methyl-5-hepten-2-one and 4-oxopentanal at maximum concentrations of 0.2 ppb and 0.7 ppb, respectively, suggested squalene from human skin oil as a reactive, ozone-consuming substance. There are indications of a source of 4-oxopentanal in the classroom, even some time after the pupils left for the day. The work presented is important for a proper description of indoor exposure, both to ozone itself and some of its reaction products when trying to quantify relations between exposure and health effects. •Ozone deposition velocities were measured in a real classroom.•Velocities agree well with lab experiments.•Ozone indoors may predominantly be removed by humans.•Avoiding product exposure means reducing ozone concentration.