GB/T 39684-2020Test method of thermal irregularities for external window opening (English PDF)

1 Scope

This standard specifies the detection, data processing, result determination, and test report of the thermal defect detection method in the area of the outer window opening

Claim:

This standard is applicable to the detection of thermal defects in the opening area of the outer window of the non-transparent building envelope by the infrared thermal imaging method:

2 Normative references

The following documents are indispensable for the application of this document: For dated reference documents, only the dated version applies to this article

Pieces: For undated references, the latest version (including all amendments) applies to this document:

JGJ/T 132 Residential Building Energy Conservation Testing Standard

3 Terms and definitions

The following terms and definitions apply to this document:

3:1

Externalwindowopening

A reserved opening for external windows is installed on the wall:

3:2

Openingside

In the detection surface, the side walls around the upper, lower, and side openings of the building’s exterior window openings:

3:3

Surrounding areaofwindowopening

The structural size of the outer window opening extends to an area of 500mm:

3:4

Testarea

It consists of the side of the hole and the area of the hole in the building envelope:

3:5

Infrared thermal imaging method infraredthermography

Using infrared thermal imaging technology, based on the principle of surface radiation temperature, the method of photographing the surface radiation temperature of the measured building:

3:6

Thermal defects thermalirregularities

When using infrared thermal imaging method to test, the temperature difference with the average temperature of the detection area is greater than 1:0K:

3:7

Gridmethod

Taking the grid as the unit, the infrared thermal image of the detection part is decomposed according to the vertical and horizontal axes, and each unit can represent the temperature of the detailed area:

Discrete processing method of image value based on degree feature: