GB/T 458-2008 in English

《GB/T 458-2008纸和纸板透气度的测定》由TC141（全国造纸工业标准化技术委员会）归口，主管部门为中国轻工业联合会。
本标准是对GB/T 458-2002《纸和纸板透气度的测定（肖伯尔法）》、GB/T 2679.13-1996《纸和纸板透气度的测定（中等范围）本特生法》和GB/T 5402-2003《纸和纸透气度的测定（中等范围）葛尔莱法》三项标准的整合修订，并代替以上三项标准。
本标准规定了纸和纸板透气度的三种测定方法：葛尔莱法、肖伯尔法、本特生法。
本标准适用于透气度在1×10-2u m／(Pa・s)～1×102 u m／(Pa・s)之间的纸和纸板。
本标准不适用于表面粗糙度较大，且不能被牢固夹紧的纸和纸板，如皱纹纸或瓦楞纸板。
本标准与GB/T 2679.13-1996、GB/T 458-2002和GB/T 5402-2003相比，有如下变化：
――将仪器结构及工作原理以附录的形式加以介绍，以利于本标准主体的条理性；
――在葛尔莱方法中，因仪器过时，故将夹板上置型仪器删除，相关标准内容也予以相应删减，请使用本标准的各方注意相关变化。

Scope

This standard specifies three methods for the determination of air permeability of paper and paperboard: Gurley method, Schober method and Bendtsen method. This standard applies to paper and cardboard with an air permeability between 1×10^-2μm/(Pa•s) and 1×10²μm/(Pa•s). This standard is not applicable to paper and paperboard that have a rough surface and cannot be firmly clamped, such as crepe paper or corrugated board.

Foreword
1 Scope
2 Normative references
3 Terms and definitions
4 Measurement procedures of Gurley method
5 Measurement procedures of Schopper method
6 Measurement procedures of Bendtsen method
7 Test report
APPENDIX A (Normative) Gurley air permeance tester
APPENDIX B (Normative) Schopper air permeance tester
Appendix C (Normative) Bendtsen air permeance tester