PD 6499:1981

Cooperating organizations
National foreword
Introduction
Section one - General and definitions
1 Scope
2 Object
3 Definitions
Section two - Insulation co-ordination
4 Basic principles of insulation co-ordination
Section three - Clearances in air
5 Influencing factors
6 Description of the fundamental factors influencing
    clearance
7 Description of the other factors which may influence
    a clearance
8 Dielectric tests
Section four - Creepage distances
9 General
10 Specification of the influencing factors
11 Dimensioning of creepage distances
12 Measurement of creepage distances and clearances
Appendices
A Altitude correction factors
B Transient overvoltage control means (surge arrestor
    devices)
C Example of dimensioning procedure for clearances and
    creepage distances
Explanatory note
    Application guide for clearances and insulation
    co-ordination based on clearance

States a principle of insulation co-ordination based upon a series of standardized impulse withstand voltage levels related to the dimensioning of clearances and creepage distances. Intended as a guide for technical bodies.