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Ozone reactions that occur on material surfaces can lead to elevated concentrations of oxidized products in the occupied space of buildings. However, there is little information on the impact of materials at full scale, especially for green building materials. Experiments were completed in a 68 m 3 climate-controlled test chamber with three certified green building materials that can cover large areas in buildings: (1) recycled carpet, (2) perlite-based ceiling tile and (3) low-VOC paint and primer on recycled drywall. Ozone deposition velocity and primary and secondary emission rates of C 1 to C 10 saturated carbonyls were determined for two chamber mixing conditions and three values of relative humidity. A direct comparison was made between ozone deposition velocities and carbonyl yields observed for the same materials analyzed in small (10 L) chambers. Total primary carbonyl emission rates from carpet, ceiling tile and painted drywall ranged from 27 to 120 μg m −2 h −1 , 13 to 40 μg m −2 h −1 , 3.9 to 42 μg m −2 h −1 , respectively. Ozone deposition velocity to these three materials averaged 6.1 m h −1 , 2.3 m h −1 and 0.32 m h −1 , respectively. Total secondary carbonyl emissions from these materials ranged from 70 to 276 μg m −2 h −1 , 0 to 12 μg m −2 h −1 , and 0 to 30 μg m −2 h −1 , respectively. Carbonyl emissions were determined with a transient approximation, and were found to be in general agreement with those found in the literature. These results suggest that care should be taken when selecting green building materials due to potentially large differences in primary and secondary emissions. |
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