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Evaluating the Oxidative Potential of Indoor and Outdoor Particles with an EPR Assay
Published
Author(s)
Shahana S. Khurshid, Steven Emmerich, Andrew K. Persily
Abstract
The hydroxyl radical (OH) generating capacity of particles has been measured in several outdoor locations, but it remains unquantified in indoor environments where extended periods of exposure are likely. Total suspended particle samples were collected inside and outside an unoccupied manufactured test house in Maryland, USA. The oxidative potential of particles was determined using electron paramagnetic resonance (OP_EPR) to quantify the OH produced when particles are placed in a hydrogen peroxide solution. The mean OP_EPR of indoor particles was about 75 % of the mean OP_EPR of outdoor particles on a sampling volume basis. Given that indoor particle counts were lower than outdoor particle counts, the ratio of OPEPR of indoor particles to the OPEPR of outdoor particles will be higher on a mass basis. Air change rate, temperature, and relative humidity were concurrently measured in order to assess the role of these parameters on the oxidative potential of particles.
Proceedings Title
14th International Conference on Indoor Air Quality and Climate Conference
Khurshid, S.
, Emmerich, S.
and Persily, A.
(2016),
Evaluating the Oxidative Potential of Indoor and Outdoor Particles with an EPR Assay, 14th International Conference on Indoor Air Quality and Climate Conference, Ghent, BE, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=920598
(Accessed October 10, 2025)