BS IEC 60709 : 2004

FOREWORD
INTRODUCTION
1 Scope
2 Normative references
3 Terms and definitions
4 General principles for separation within I&C systems
  important to safety
  4.1 General
  4.2 Design errors
  4.3 I&C system failure events
      4.3.1 Single random failure
      4.3.2 Multiple failures from a single common cause
  4.4 Plant failure events
      4.4.1 Environmental conditions
      4.4.2 Electromagnetic interference
      4.4.3 Failure of plant systems, equipment or structures
      4.4.4 Operator error
  4.5 External failure events
      4.5.1 Natural events
      4.5.2 External man-made causes
  4.6 Special operating conditions
  4.7 Separation issues at existing plants
5 Design basis
  5.1 Fire protection
  5.2 Environmental conditions during and after accidents
  5.3 Isolation devices
      5.3.1 General
      5.3.2 Isolation characteristics
      5.3.3 Actuation priority
  5.4 Independence from control systems
6 Requirements for cabling separation
  6.1 General requirement
  6.2 Separation
      6.2.1 Separation of redundant cables inside the I&C
            system important to safety
      6.2.2 Lesser separation distances
      6.2.3 Associated circuits
      6.2.4 Separation of system cables of different safety
            categories
      6.2.5 Separation of signal cables from power cables
      6.2.6 Separation of cables from tubes or pipes
      6.2.7 General routing considerations
      6.2.8 Control room cabinets, desks, panels and related
            cables
  6.3 Thermal and physical protection
  6.4 Fire protection
  6.5 Identification

Applies to nuclear power plant instrumentation and control (I&C) systems, and their cables, that are important to safety, as defined in IAEA Safety Guide NS-G-1.3. It is also applicable to temporary installations which are part of those I&C systems important to safety (for example, auxiliary equipment for commissioning tests and experiments).