SL-90-08-3 -- Smoke Management in Large Spaces-Sizing Smoke Vents, Flow Rates, and Temperatures PDF

The Norwegian National Office of Building Technology and Administration released new guidelines for smoke management design in 1989. The guidelines are partly based on British smoke plume models and NFPA data. This paper demonstrates aspects of the plume model and how it is modified to take account of high-rack storages. The fire growth, i.e., fire area development, vs. time is also shown. A very interesting aspect is how the smoke layer temperature affects the smoke vent size-it simplifies vent design- and, as a result, it has led to a new and simplified method for assessing the effect of combined smoke ventilation and sprinklers. This paper demonstrates the enormous amount of smoke that must be taken into account when mechanical smoke ventilation is used. Exhaust temperatures and their influence on smoke layer temperature and volumetric flow rate caused by different stacking methods are also shown. Examples illustrate how the design method may be used. Five tables give the design basis. Finally, a new approach utilising a smoke ventilation system solely for post-fire smoke extraction is demonstrated.

KEYWORDS: smoke ventilation, sprinklers, models, designing, smoke, air flow, temperature, warehouses, atria, vents, sizing.