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Author
Lougheed, G. D. | McBride, P. J. | Carpenter, D. W.
Title
Positive Pressure Ventilation for High-Rise Buildings.
Coporate
National Research Council of Canada, Ottawa, Ontario
Report
IRC Research Report 102, August 2002, 99 p.
Distribution
FOR MORE INFORMATION CONTACT: National Research Council of Canada, Institute for Research in Construction, Ottawa, Ontario, K1A 0R6, Telephone (613) 993-2607, Fax: (613) 952-7673, Email: Irc.Client-Services@nrc.ca Website: http://www.nrc.ca/irc/ircpubs OR FULL DOCUMENT IN PDF at Website: http://www.nrc.ca/irc/fulltext/rr102/rr102.pdf
Keywords
high rise buildings | ventilation | fans | vents | structures | air flow | fire departments | fire fighting | fire tests | couches | burners | beds (furniture) | stairwells | test facilities | heat release rate | corridors | pressure differential | carbon dioxide | temperature | smoke | compartments | mattresses | optical density
Abstract
Positive pressure ventilation (PPV) is achieved by placing fans outside a building and blowing air into the structure. When appropriate openings or vents are used in the structure, the airflow produced by the fan exhausts contaminants to the outside. Fire departments have used PPV as a means to ventilate contaminated atmospheres after initial knockdown and extinguishment of a fire. In Ontario, the use of positive pressure ventilation is still relatively new. However, its use as a tool to improve conditions is being explored by a number of fire departments, including the Ottawa Fire Department. In 1998, a joint project with Canada Mortgage and Housing Corporation, Ottawa Fire Department, Tempest Technology Corporation, the Co-operators Insurance and National Research Council Canada (NRC), was initiated to investigate the use of PPV to vent smoke from high-rise buildings. NRC's ten-storey facility was used for the investigations. In the initial phase of the project, baseline tests were conducted to determine the airflow through an open exterior stair shaft door and pressures in the stair shaft produced by the fans under non-fire conditions. A second series of baseline tests were conducted using propane burners to simulate conditions (temperature and CO2 concentrations) produced by a fire. These tests were used to investigate the effect of various parameters, including vent area on the effectiveness of the PPV system. Subsequently, the PPV system was used to vent smoke produced by fires involving typical residential furniture (sofas and beds). In addition, a limited number of tests were conducted with sprinklered heptane pan fires to investigate the effectiveness of the system in venting cool smoke.