skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Sandwich pressurization systems for smoke control

Journal Article · · ASHRAE Journal (American Society of Heating, Refrigerating and Air-Conditioning Engineers); (United States)
OSTI ID:6988222
 [1]
  1. South Australian Metropolitan Fire Service, Adelaide (Australia)

Australian building legislation has in the past paid little attention to smoke control within multi-story buildings apart from the old Australian Standard 1668, Fire Precautions in Buildings with Air Handling Systems. The objective of that standard was to prevent the migration of smoke to other parts of a building by way of the installed air-conditioning ductwork. However, there was no requirement in the old AS-1668 or in Australian building regulations (AMUBC) to minimize smoke spread through a multi-story building by connecting paths other than the air-conditioning ductwork (building service, elevator and ventilation shafts). This paper reports that because the old standard only applied to buildings employing a central air handling plant, in those early days (before some authorities woke up to the loophole) it was possible to construct a multi-story building with individual on-floor (unitary) air conditioners, to save the expense of a smoke control system. Occupants would then, for their safety, rely solely upon required stair pressurization systems to provide smoke-free paths of egress. Local ad hoc tests have demonstrated that smoke will migrate from the fire floor to other parts of a building via transfer paths such as elevator shafts, construction joints and ventilation ducts. The traditional AS-1668 modus operand, at time of fire, consists of running the building air-conditioning plant in what we now call the purge mode. Using economy cycle dampers, all floors (including the fire floor) are supplied with 100% fresh air and exhausted to atmosphere. This is usually accomplished via a return air shaft, using either dedicated smoke spill fans or the air-conditioning return air fans.

OSTI ID:
6988222
Journal Information:
ASHRAE Journal (American Society of Heating, Refrigerating and Air-Conditioning Engineers); (United States), Vol. 34:11; ISSN 0001-2491
Country of Publication:
United States
Language:
English