AAAR 35th Annual Conference October 17 - October 21, 2016 Oregon Convention Center Portland, Oregon, USA
Abstract View
Impact of Environmental Tobacco Smoke on Membrane-Based Energy Recovery Ventilators
ALEXANDER SYLVESTER, Amin Engarnevis, Ryan Huizing, Steven Rogak, Sheldon Green, University of British Colombia
Abstract Number: 676 Working Group: Indoor Aerosols
Abstract Environmental Tobacco Smoke (ETS) is a mixture of aerosols and chemical compounds known to cause health risks, respiratory irritation, and odor discomfort. ETS is the product of ‘Main-Stream’ smoke, exhaled by the smoker, and ‘Side-Stream’ smoke, released from the tip of the lit cigarette. While the relative quantity of these components varies, the Side-stream component is always dominant. In order to meet building code requirements, HVAC systems in ETS environments must supply a significant amount of outdoor air to dilute the ETS, making them extremely demanding of energy. The use of an Energy Recovery Ventilator (ERV) has the potential to substantially reduce this energy cost by transferring moisture and heat between exhaust and intake air streams.
This work investigates the influence of ETS on the performance of paper- and polymer-based materials used in ERVs via accelerated ETS exposure tests using an analogue of Side-Stream ETS, generated by drawing air through a lit cigarette and diluting the resultant smoke with fresh air.
We find that, as a result of ETS loadings equivalent to about two years of operation in a typical casino in North America, the water vapor flux through polymer- and paper-based membrane samples is reduced to 70%-34% of the initial value. In general, polymer-based membranes have much greater initial water vapor fluxes making them more desirable candidates for in-field longevity. Results from pressurized air leakage and crossover tests indicate that paper-based membranes are significantly more permeable to gases, odors, and other unwanted contaminants.
While we have found that an upstream filter has no significant effect on VOC levels, others have shown that a filter can significantly reduce ETS PM levels. Because the PM component is likely the cause of degradation, an upstream filter could be an effective method of extending ERV life in smoking environments.