GB/T 22921-2008 "Paper and board—Determination of water vapour transmission rate of thin sheet materials—Dynamic airflow method and static gas method" specifies two methods for determining the water vapour transmission rate of thin sheet materials, applicable to paper and board thin sheet materials. The dynamic airflow method calculates the transmission rate by measuring the amount of water vapour passing through the sample, while the static gas method derives results based on changes in gas concentration. The standard clearly outlines requirements for sample handling, instrument calibration, and result calculation to ensure the accuracy and comparability of the tests.
This summary is not the original standard text and is for reference only. For accurate information, please obtain it through official channels.
| Status | Active | ||
|---|---|---|---|
| CCS | Y30 | ICS | 85.010 |
| Release Date | 2008-12-30 00:00:00 | Implementation Date | 2009-09-01 00:00:00 |