Experimental studies in removal of accumulated ETS and the effectiveness of ETS leakage control were carried out in a model smoking room using nicotine, 3-ethenylpyridine (3-EP), fine particles of 2.5 μm diameter and smaller (PM_2.5) and ultrafine particles (UFP) as the ETS tracers. The objectives of the study were to investigate the effectiveness of the designated smoking room equipped with displacement ventilation system under different ventilation rates (10 – 58 L/s per person) on removing the ETS tracers. The extent of ETS leakage through different door operating scenarios under various ventilation rates were intensively studied. In particular, a manikin installed on rail was used to study the human movement effect on leakage of the ETS tracers. A double door anteroom design was also...[ Read more ]

Experimental studies in removal of accumulated ETS and the effectiveness of ETS leakage control were carried out in a model smoking room using nicotine, 3-ethenylpyridine (3-EP), fine particles of 2.5 μm diameter and smaller (PM_2.5) and ultrafine particles (UFP) as the ETS tracers. The objectives of the study were to investigate the effectiveness of the designated smoking room equipped with displacement ventilation system under different ventilation rates (10 – 58 L/s per person) on removing the ETS tracers. The extent of ETS leakage through different door operating scenarios under various ventilation rates were intensively studied. In particular, a manikin installed on rail was used to study the human movement effect on leakage of the ETS tracers. A double door anteroom design was also incorporated into the smoking room to study its effectiveness in ETS leakage prevention.

It was observed that under at least 5 Pa negative pressure, 3-5 times of a typical office fresh air supply rate, direct air exhaust without air recirculation, and the use of sliding door, there was no distinguishable leakage of ETS tracers when the smoking room door was closed. Significant leakage of ETS tracers could occur when the smoker, simulated by the manikin installed on a rail, was walking out of the room. The double-door anteroom design showed improvement to ETS leakage prevention but the problem still could not be completely mitigated. Residual nicotine levels were also observed after the smoking activity was stopped in the room which indicates a substantial length of purging time is needed to minimize the exposure of ETS by the cleaning and maintenance workers. This study has provided insightful information on the use of UFP as the indicator for monitoring the exposure and leakage of ETS. The impact of the human movement on the contaminant transport was studied and this could also provide useful information for the effects of human activities on the IAQ multi-compartmental modeling.