Review On Design Guides For Smoke Management System in An Atrium
Review On Design Guides For Smoke Management System in An Atrium
Review On Design Guides For Smoke Management System in An Atrium
65-87, 2005
ABSTRACT
Common design guides on smoke management in atria used will be reviewed in this paper. Different approaches adopted in those guides are outlined with the smoke physics behind explained. Engineering principles on smoke dynamics of these design guides are observed to be similar. Basically, methods are on imposing opposite strong airflow to prevent smoke spreading, applying pressure differentials against a physical barrier, dilution of smoke and extracting smoke. Smoke ventilation appears to be a common approach for smoke management in an atrium. An acceptable smoke layer interface height can be kept; or at least, reducing the descending rate of smoke layer. These guides give general principles for the design, but not cover all the atria, especially those in new construction projects of the Far East. Further, guidance on solving practical problems frequently encountered in these areas is discussed.
1.
INTRODUCTION
Extracting concerned.
smoke
away
from
spaces
Smoke generated from a fire in an atrium itself or in spaces adjacent to the atrium may spread rapidly. Consequence will be quite serious in exposing a number of occupants to risk. The time for escape will be reduced and the fire-fighting activities will be affected, though the smoke will be quite cool due to the large atrium space. Smoke management systems [1-3], which are defined as engineered systems including all methods that can be used singly or in combination to reduce smoke production or to modify smoke movement, are essential to provide a tenable environment for the safe evacuation of occupants. Approaches to smoke management design in atria have been introduced in some codes and engineering guides. While design approaches in these guides might be different, the engineering principles behind are similar. For example, a stable smoke layer might be assumed so that a fire zone model will work. By solving a set of equations describing smoke physics, smoke management systems can be designed. Smoke management systems are operated based on: Imposing opposite airflow to limit smoke spreading such as longitudinal ventilation in tunnels; Applying pressure differential against physical barrier, such as staircase pressurization; Diluting smoke by purging large amount of air;
Guidance to atrium smoke control systems designs within the UK are: The British Standards BS 5588: Part 7 Code of practice for the incorporation of atria in buildings [4]; The CIBSE Guide E Fire engineering [5]; The BRE Report 258 Design approaches for smoke control in atrium buildings [6]; and The BRE Report 368 Design methodologies for smoke and heat exhaust ventilation [7].