NATIONAL FOREWORD

This Indian Standard (Part 4) which is identical with ISO 7240-4 : 2003 ‘Fire detection and alarm systems — Part 4: Power supply equipment’ issued by the International Organization for Standardization (ISO) was adopted by the Bureau of Indian Standards on the recommendation of the Fire Fighting Sectional Committee and approval of the Civil Engineering Division Council.

This standard is published in various parts. Other parts in this series are:

Part 2 Control and indicating equipment

Part 3 Audible alarm devices

Part 5 Point-type heat detectors

Part 6 Carbon monoxide fire detectors using electro-chemical cells

Part 7 Point-type smoke detectors using scattered light, transmitted light or ionization

Part 11 Manual call points

Part 12 Line type smoke detectors using a transmitted optical beam

Part 15 Point type fire detectors using scattered light, transmitted light or ionization sensors in combination with a heat sensor1)

Part 16 Sound system control and indicating equipment

Part 17 Short-circuit isolators

Part 20 Aspirating smoke detectors

Part 22 Smoke-detection equipment for ducts

Part 23 Visual alarm devices

This standard is published on the basis of mandatory functions, which are to be provided on all equipment, and optional (each with its own requirements). It is intended that the options be used for specific applications, as recommended in application guidelines.

Each optional function is included as a separate entity, with its own set of associated requirements, in order to permit equipment with many different combinations of functions to comply with this standard.

Other functions associated with fire detection and alarm can also be provided, even if not specified in this standard.

The text of ISO Standard has been approved as suitable for publication as an Indian Standard without deviations. Certain conventions and terminologies are, however, not identical to those used in Indian Standards. Attention is particularly drawn to the following:

a) Wherever the words ‘International Standard’ appear referring to this standard, they should be read as ‘Indian Standard’.

b) Comma (,) has been used as a decimal marker while in Indian Standards, the current practice is to use a point (.) as the decimal marker.