BS 6993-2:1990

Foreword
Committees responsible
Method
1 Scope
2 Definitions
3 Symbols
4 Equipment
5 Conditions for test
6 Determination of measurements following calibration
Appendices
A Values to be used in U-value calculations
B Worked example of correction to standardized total
   surface resistance
Figures
1 Location of test element in surround panel
2 Interpolation of total average surface resistances

Method for measuring the transmittance of the central area of single, double or multiple glazing using hot box apparatus complying with BS 874-3.1. The edge effect due to the thermal bridge through the spacer of double or multiple glazing is effectively eliminated by this method.

This Part of BS 6993 describes a method for measuring the U-value (thermal transmittance) of the central area of single, double or multiple glazing using hot-box apparatus complying with BS 874-3.1. The edge effect, due to the thermal bridge through the spacer of double or multiple glazing, is effectively eliminated in this method.

The method is designed to measure the U-value of the glazing alone, i.e. the glass (or alternative glazing material) and any enclosed air space, and the additional information required in the test reports of clause 8 and A.9 of BS 874-3.1:1987.

Appendix A specifies values to be used in the calculation of a U-value in accordance with BS 6993-1, when such a calculated value is to be compared with that obtained by direct measurement in accordance with this Part of BS 6993.

Appendix A gives a worked example, which illustrates the use of this Part of BS 6993.

NOTE The titles of the publications referred to in this standard are listed on the inside back cover.