Components for smoke andheatcontrol systems -
Part4:Functionalremendationsandcalculationmethodsforsmokeandheat exhaustventilation systems employingsteady-statedesignfires-Codeofpractice
Committeesresponsibleforthis BritishStandard
The preparation of this British Standard was entrusted to Technical Committee FSH/25 Smoke heat control systems and ponents upon whichthe following bodies were represented:
Association of Roof Light Manufacturers BRE/LPC LaboratoriesBritish Blind and Shutter Association Building Services Research and InformationConsumer Policy Committee of BSIFire Resistant Glass and Glazing Federation HEVAC AssociationInstitution of Fire Engineers London Fire and Emergency Planning AuthorityOPDM-Building Regulation DivisionODPM Office of the Deputy Prime Minister Smoke Vent AssociationSteel Window Association Co-opted members
This British Standsrd was published under tbe authorityof the Standards Policy and Strategy Committee on29 August 2003
Amendments issued since publication
C BSI 29 August 2003
Amd. No. Date Comments
The following BSI referencesrelate to the work on this British StandardCommittee reference FSH/25 Draft for ment 0/541350 DC
ISBN 0 580 42233 X
Contents
Inside front cover PageForeword Committees responsible i0 Introduction 11 Scope Normative references 52 3 Terms definitions symbols and units 5 64 General remendations 145 9 Performance remendations Calculation procedures 22 197 Interaction with other fire protection systems and other buildingAnnex A (informative) Default value heat release rates systems 40 44Annex B (informative) The plume rising direetly from the fire into a smokereservoir Annex C (informative) The flow of hot smoky gases out of a fire-room into an 44adjacent space 47beyond a fire-room's opening or window Annex D (informative) The flow of hot smoky gases under a soffit projecting 51Annex E (informative) The spill plume 56Annex G (informative) The influence of zones of overpressure and/or zones of Annex F (informative) The smoke reservoir and ventilators 56suction upon a SHEVS Annex H (informative) Deflection of free-hanging smoke barriers 60 63Annex I (informative) Plenum chamber 67Annex J (informative) Atrium depressurization 69fire-fighting actions Annex K (informative) The interaction of sprinklers a SHEVS and 79pressure remended for a pressure diferential system Annex L (informative) The effect of a buoyant layer on the minimum 08Bibliography 83Figure 1 - Design regions for a single-volume space 19Figure 2 - Design regions for a space where there is a spill plume Figure 3a) Adhered plume 21Figure 3b) Free plume 29Figure 4a) - Deep balcony projection 30Figure 4b) Shallow balcony projection Figure 5 Flow resistance through openings in an atrium 31 39Figure 6 Early (or premature) stratification of smoke 41Figure B.1 Limiting size of a cellular room Figure B.2 Smoke ventilation in a single-storey mall 45 47Figure C.1 Flow out of an opening with high balcony 48balcony Figure C.2 Flow out of an opening with downstand and projecting 49Figure D.1 Smoke spreading sideways beneath a projecting canopy orbalcony Figure D.2 - Smoke confined to a pact spill plume by channelling 52screens Figure D.3 - Slot exhaust 53Figure F.1 Use of smoke transfer ducts in otherwise stagnant regions 55 59
Figure G.1 Zones of overpressure on a roof with an outstanding Pagestructure 60Figure G.2 Assessment of h in case of a roof with an outstanding structure and a parapet 61Figure G.3 - Zones of suctions affecting the location of inlet openings 62Figure H.2 - Forces acting on a deflecting smoke barrier closing an Figure H.1 - Forces acting on a deflected smoke barrier 64opening 66Figure I.1 Figure J.1 - Neutral pressure plane throughflow ventilation Plenum chamber 68 70Figure J.2 - Neutral pressure plane exhaust larger than inlet 71Figure J.3 Neutral pressure plane above highest leaky storey Figure J.4 - Principles of hybrid smoke ventilation system mass 72flow-based 76Figure J.5 Principles of hybrid smoke ventilation system temperature-based 78Figure L.1 The neutral pressure plane and layer buoyant pressure 81Table 2 Minimum clear height above escape routes Table 1 - Default values of design fires 24 25Table 3 - Convective heat flux at the room opening 26
Foreword
This part of BS 7346 has been prepared by Technical Committee FSH/25. The other parts prising BS 7346 are:
Part I: Specification for natural smoke and heat exhaust ventilators;
Part 2: Specification for powered smoke and heat exhaust ventilators; Part 3: Specification for smoke curtain8.
The above three standards are eventually to be replaced by EN 12101 Smokeand heat control systems consisting of the following parts:
Part I: Specification for smoke barriers -- Remendations test methods;Part 2: Specification for natural smoke and heat exhaust ventilators;--Part 3: Specification for powered smoke and heat exhaust ventilators;--Part 4: Smoke and heat control installationsKits; -Part 6:Functional requirements and calculation methods ponents systems; installation and testing procedures for pressure differential smoke control-Part 7: Smoke control ducts;-Part 8: Smoke control dampers; -Part 9: Power supply equipment;-Part 10: Control equipment.
EN 12101 forms part of a series of Buropean Standards which are planned to cover:
COg systems (EN 12094); sprinkler systems (EN 12259);explosion protection systems (BS EN 26184); powder systems (BS EN 12416); foam systems (pr EN 13565);hydrant and hose reel systems (BS EN 671); semi-rigid hose systems (EN 694).
As a code of practice this British Standard takes the form of guidance andremendations. It should not be quoted as if it were a specification and particular care should be taken to ensure that claims of pliance are notmisleading.
This publiation does not purport to include allthe necessary provisions of acontract. Users are responsible for its correct application.
Compliance with a British Standard does not of itself confer immunity
from legal obligations.
Summary of pages
This document prises a front cover an inside front cover pages i to iv pages 1 to 83 and a back cover.
The BSI copyright notice displayed in this document indicates when the document was last issued.
