ISO 21927-5:2018

Smoke and heat control systems — Part 5: Powered smoke exhaust systems — Requirements and design

This document applies to powered smoke exhaust systems in spaces with a large area and with a ceiling height of minimum 3 m, in which smoke protection is required. It includes tables and calculation methods for the design of clear layers in order to comply, inter alia, with the requirements of various protection objectives. This document includes information and provisions concerning the requirements for powered smoke exhaust systems, their design and rules for their installation. NOTE The requirements for testing the ventilators are dealt with in ISO 21927‑3. Other parts of the ISO 21927 series of standards deal with the power supply (ISO 21927‑10), control equipment (ISO 21927‑9) and smoke control ducts and smoke control dampers (ISO 21927‑7 and ISO 21927-8 respectively). Design, as specified in this document, does not apply to: — spaces with fixed gas extinguishing systems; — storage facilities for hazardous materials; — spaces in which there is a risk of explosions; — corridors; — stairwells.

Installations pour l'extraction de fumée et de chaleur — Partie 5: Systèmes d'extraction de fumée mécaniques — Exigences et planification

General Information

• Status: Published
• Publication Date: 27-Nov-2018
• ICS: 13.220.20 - Fire protection
• Technical Committee: ISO/TC 21/SC 11 - Smoke and heat control systems and components
• Drafting Committee: ISO/TC 21/SC 11 - Smoke and heat control systems and components
• Current Stage: 9060 - Close of review
• Start Date: 04-Jun-2029

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 21927-5
First edition
2018-11
Smoke and heat control systems —
Part 5:
Powered smoke exhaust systems —
Requirements and design
Installations pour l'extraction de fumée et de chaleur —
Partie 5: Systèmes d'extraction de fumée mécaniques — Exigences et
planification
Reference number
ISO 21927-5:2018(E)
©
ISO 2018

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ISO 21927-5:2018(E)

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ii © ISO 2018 – All rights reserved

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ISO 21927-5:2018(E)

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Design principles . 2
4.1 General . 2
4.2 Height of space . 4
4.3 Target height of the clear layer, d, in a smoke reservoir, A . 4
R
4.4 Area of smoke reservoir, A . 4
R
4.5 Air supply . 4
4.5.1 General. 4
4.5.2 Natural air replacement. 5
4.5.3 Powered air replacement . 5
4.6 Duration of fire growth to be assumed in the design . 5
4.7 Design group . 5
5 Calculating the volume flow of the smoke gases to be exhausted . 6
5.1 Basis of the calculation . 6
5.2 Using the tables .
...