No abstract

The effects of different kinds of room ventilation were evaluated in an experi mental chamber and in kitchens of four residences in Beijing. Carbon monox ide was used as a tracer gas in the chamber, and this together with nitric oxide and nitrogen dioxide concentrations from the gas appliances were measured in the chamber and the kitchens. The ventilation styles evaluated were natural ventilation, an exhaust fan and a kitchen range hood. Their ventilation effec tiveness was related to design, air flow, the distance between an appliance and air vent, and position of the appliance in the kitchen. A kitchen range hood above the appliance associated with an extra fan installed in a high window was found to be the most effective way to control indoor air quality in the kitchens.

The effects of different kinds of room ventilation were evaluated in an experimental chamber and in kitchens of four residences in Beijing. Carbon monoxide was used as a tracer gas in the chamber, and this together with nitric oxide and nitrogen dioxide concentrations from the gas appliances were measured in the chamber and the kitchens. The ventilation styles evaluated were natural ventilation, an exhaust fan and a kitchen range hood. Their ventilation effectiveness was related to design, air flow, the distance between an appliance and air vent, and position of the appliance in the kitchen. A kitchen range hood above the appliance associated with an extra fan installed in a high window was found to be the most effective way to control indoor air quality in the kitchens.

The material in this document is covered by the provisions of the Copyright Act, by Canadian laws, policies, regulations and international agreements. Such provisions serve to identify the information source and, in specific instances, to prohibit reproduction of materials without written permission. For more information visit http://laws.justice.gc.ca/en/showtdm/cs/C-42Les renseignements dans ce document sont protégés par la Loi sur le droit d'auteur, par les lois, les politiques et les règlements du Canada et des accords internationaux. Ces dispositions permettent d'identifier la source de l'information et, dans certains cas, d'interdire la copie de documents sans permission écrite. Pour obtenir de plus amples renseignements : http://lois.justice.gc.ca/fr/showtdm/cs/C-42 ). This is a low concentration that commercially available formaldehyde sensors have great difficulty to detect both accurately and continuously. In this paper, we report a formaldehyde gas detection system which is capable of pre-concentrating formaldehyde gas using absorbent, and subsequently thermally desorbing the concentrated gas for detection by the electrochemical sensor. Initial results show that the system is able to detect formaldehyde gas at the ppb level, thus making it feasible to detect trace amount of formaldehyde in indoor environments.

This study aimed to prevent chemical air pollution and reduce its influence on occupants' health in a university building under renovation. Since starting the renovation work, the occupants' health status was monitored using questionnaires every summer and winter. According to a first questionnaire collected before the renovation, subjective symptoms were not observed. However, some occupants complained about odor after moving into their new rooms. Therefore, all interior materials used for the construction work were examined in small chambers to obtain their chemical emission characteristics. The assembled floor, which was a polyvinyl chloride floor sheet combined with a concrete slab by adhesive, was predicted to be the main source of odor in the renovated rooms. Two strategies were implemented individually in rooms to remove these odorous chemicals; a chemical filter in indoor air conditioning units and forced ventilation with hot-humid outdoor air. The performance of each technique was validated by measuring the indoor concentration before and after operation. These results showed that both strategies had a significant effect on reducing volatile organic compounds (VOCs), in a practical way.