BS 5691-1:1995

Committees responsible
National foreword
Foreword
Introduction
Section one. General
1 Scope
2 General considerations
3 Principles of evaluation and difinitions
4 Selection of test procedures - General guidelines
Section two. Experimental procedures
5 Selection of end-points
6 Preparation of test specimens
7 Establishment of initial property value and number
   of test specimens
8 Exposure temperatures and times
9 Ageing ovens
10 Environmental conditioning
11 Procedure
Section three. Evaluation
12 Analysis of test results and determination of thermal
   endurance characteristics
13 Treatment and presentation of test data which fail to
   satisfy the statistical requirements
14 Test report
Appendices
A Notes on mechanisms of thermal degradation
B The halving interval
C Dispersion and non-linearity
D The thermal endurance profile (TEP)
Table
I Suggested exposure temperatures and times
Figures
1 Determination of the time to reach the end-point
   criterion at each temperature. Property variation
2 Thermal endurance graph. T1: Temperature index. HIC:
   Halving interval
3 Thermal endurance graph. RTI: Relative temperature
   index. HIC (A): Halving interval
Annex
ZA (normative) Other international publications quoted
    in this standard with the references of the relevant
    European publications

Gives principles of test procedures to evaluate the thermal endurance of insulating materials and combinations of such materials. Shows the basic analysis to derive the temperature index and halving interval from test results.