ISO 7240-31:2022

Fire detection and alarm systems — Part 31: Resettable line-type heat detectors

This document applies to resettable line-type heat detectors consisting of a sensing element distributed either continuously or discretely at close intervals along its length and connected to a sensor control unit, either directly or through an interface module, intended for use in fire detection and fire alarm systems installed in and around buildings and other civil engineering works. Examples of such technology are an optical fibre, a pneumatic tube, or an electrical sensor cable This document specifies the requirements and performance criteria, the corresponding test methods, and provides for the assessment. This document also covers resettable line-type heat detectors intended for use in the local protection of plants and equipment. This document does not cover non-resettable line-type heat detectors that can only respond once and are based on fixed temperature electrical cables.

Systèmes de détection et d'alarme incendie — Partie 31: Détecteurs de chaleur en ligne resetable

General Information

• Status: Published
• Publication Date: 05-Sep-2022
• ICS: 13.220.20 - Fire protection
• Technical Committee: ISO/TC 21/SC 3 - Fire detection and alarm systems
• Drafting Committee: ISO/TC 21/SC 3/WG 27 - Line-type heat detectors
• Current Stage: 6060 - International Standard published
• Start Date: 06-Sep-2022
• Due Date: 28-May-2022
• Completion Date: 06-Sep-2022

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 7240-31
First edition
2022-09
Fire detection and alarm systems —
Part 31:
Resettable line-type heat detectors
Systèmes de détection et d'alarme incendie —
Partie 31: Détecteurs de chaleur en ligne resetable
Reference number
ISO 7240-31:2022(E)
© ISO 2022

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ISO 7240-31:2022(E)
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© ISO 2022
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Published in Switzerland
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ISO 7240-31:2022(E)
Contents Page
Foreword .viii
Introduction .ix
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Requirements . 3
4.1 General . 3
4.1.1 Conformance . 3
4.1.2 Heat response classes . 3
4.2 Individual alarm indication . 5
4.3 Signalling . 5
4.4 Repeatability . 6
4.5 Reproducibility . 6
4.6 Connection of ancillary devices. 6
4.7 Manufacturer's adjustments . 6
4.8 Software . 6
4.8.1 General . 6
4.8.2 Software design . 6
4.8.3 The storage of programs and data . 6
4.9 Sensing element fault . 7
4.10 On-site adjustment of response behaviour . 7
4.11 Maximum ambient temperature test (sensing element) . 7
4.12 Variation in supply parameters . 7
4.13 Low voltage fault. 7
4.14 Fire sensitivity for Class A and ror-only RLTHD . 7
4.15 Static response temperature test . 7
4.16 Response times from typical application temperature for ror-only RLTHD . 8
4.17 Dry heat (operational) sensor control unit . 8
4.18 Dry heat (endurance) for sensor control unit and sensing element . 8
4.19 Cold (operational) for sensing element . 8
4.20 Cold (operational) for sensor control unit . 8
4.21 Damp heat, steady-state (endurance) for sensor control unit and sensing element . 8
4.22 Damp heat, cyclic (operational) for sensing element . 8
4.23 Damp heat, cyclic (operational) for sensor control unit . 8
4.24 Damp heat, steady-state (operational) for sensor control unit . 8
4.25 Damp heat, cyclic (endurance) for sensor control unit and sensing element . 8
4.26 Shock (operational) for sensor control unit . 8
4.27 Impact (operational) for sensor control unit . 9
4.28 Impact (operational) for sensing element . 9
4.29 Vibration, sinusoidal (operational) for sensor control unit . 9
4.30 Vibration, sinusoidal (operational) for sensing element . 9
4.31 Vibration, sinusoidal (endurance) for sensor control unit . 9
4.32 Vibration, sinusoidal (endurance) for sensing element . 9
4.33 Sulfur dioxide (SO ) corrosion (endurance) for sensing element . 9
2
4.34 Sulfur dioxide (SO ) corrosion (endurance) for sensor control unit . 9
2
4.35 Electromagnetic immunity . 9
5 Test methods . 9
5.1 General . 9
5.1.1 Atmospheric conditions for tests. 9
5.1.2 Operating conditions for tests. 10
5.1.3 Mounting arrangements . 10
5.1.4 Tolerances . 10
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ISO 7240-31:2022(E)
5.1.5 Procedure for measurement of response time . 10
5.1.6 Provision for tests . 11
5.1.7 Test schedule . 12
5.2 Individual alarm indication . 14
5.3 Signalling . 14
5.4 Repeatability . 14
5.4.1 Object of the test . 14
5.4.2 Test procedure. 14
5.4.3 Requirements . 15
5.5 Reproducibility . .15
5.5.1 Object of the test . 15
5.5.2 Test procedure. 15
5.5.3 Requirements .15
5.6 Connection of ancillary devices. 15
5.7 Manufacturer's adjustments .15
5.8 Requirements for software-controlled detectors . 15
5.9 Sensing element fault . 15
5.9.1 Object of the test . 15
5.9.2 Sensing element operational continuity . 16
5.9.3 Requirements . 16
5.10 On-site adjustment of response behaviour . 16
5.11 Maximum ambient temperature test (sensing element) . 16
5.11.1 Object of the test . 16
5.11.2 Mounting of the sensing element . 16
5.11.3 Test procedure. 16
5.11.4 Requirements . 16
5.12 Variation in supply parameters . 16
5.12.1 Object of the test . 16
5.12.2 Test procedure. 17
5.12.3 Requirements . 17
5.13 Low voltage fault. 17
5.13.1 Object of the test . 17
5.13.2 Test procedure. 17
5.13.3 Requirements . 17
5.14 Fire sensitivity for Class A and ror-only RLTHD . 17
5.14.1 Object of the test . 17
5.14.2 Principle . 17
5.14.3 Fire test room . 17
5.14.4 Test fires . 18
5.14.5 Mounting of the specimens . 18
5.14.6 Initial conditions . 18
5.14.7 Recording of the fire parameters and response times . 19
5.14.8 Requirements . 19
5.15 Static response temperature test . 19
5.15.1 Object of the test . 19
5.15.2 Test procedure for non-integrating linear and multipoint RLTHD . 19
5.15.3 Test procedure for integrating linear RLTHD . 21
5.15.4 Requirements .22
5.16 Response times from typical application temperature for ror-only RLTHD .22
5.16.1 Object of the test . 22
5.16.2 Test procedure.22
5.16.3 Requirements .22
5.17 Dry heat (operational) test for sensor control unit. 22
5.17.1 Object of the test . 22
5.17.2 Reference . 22
5.17.3 State of the specimen during conditioning .22
5.17.4 Conditioning . 23
5.17.5 Measurements during conditioning . 23
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ISO 7240-31:2022(E)
5.17.6 Final measurements . 23
5.17.7 Requirements .23
5.18 Dry heat (endurance) for sensor control unit and sensing element .23
5.18.1 Object of the test . 23
5.18.2 Principle . 23
5.18.3 Reference . 24
5.18.4 State of the specimen during conditioning . 24
5.18.5 Conditioning . 24
5.18.6 Final measurements . 24
5.18.7 Requirements .25
5.19 Cold (operational) for sensing element . 25
5.19.1 Object of the test . 25
5.19.2 Reference . 25
5.19.3 State of the specimen during conditioning . 25
5.19.4 Conditioning . 25
5.19.5 Measurements during conditioning . 25
5.19.6 Final measurements . 25
5.19.7 Requirements .26
5.20 Cold (operational) for sensor control unit . 26
5.20.1 Object of the test . 26
5.20.2 Reference . 26
5.20.3 State of the specimen during conditioning . 26
5.20.4 Conditioning .26
5.20.5 Measurements during conditioning . 26
5.20.6 Final measurements . 26
5.20.7 Requirements . 27
5.21 Damp heat, steady-state (endurance) for sensor control unit and sensing element . 27
5.21.1 Object of the test . 27
5.21.2 Reference . 27
5.21.3 State of the specimen during conditioning . 27
5.21.4 Conditioning . 27
5.21.5 Final measurements . 27
5.21.6 Requirements . 27
5.22 Damp heat, cyclic (operational) for sensing element .28
5.22.1 Object of the test .28
5.22.2 Principle .28
5.22.3 Reference .28
5.22.4 State of the specimen during conditioning .28
5.22.5 Conditioning .28
5.22.6 Measurements during conditioning .29
5.22.7 Final measurements .29
5.22.8 Requirements .29
5.23 Damp heat, cyclic (operational) for sensor control unit .29
5.23.1 Object of the test .29
5.23.2 Principle . 29
5.23.3 Reference . 29
5.23.4 State of the specimen during conditioning .29
5.23.5 Conditioning .29
5.23.6 Measurements during conditioning .30
5.23.7 Final measurements .30
5.23.8 Requirements .30
5.24 Damp heat, steady-state (operational) for sensor control unit .
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