Testing, paper and board

Grain can also be detected by a Mullen burst test (and tensile strength)—see Paper and board testing below. 

As a result of its hygroscopic properties, paper and board must be tested under standard climatic conditions and the samples must be conditioned in this climate for at least 4 hours before testing (sample conditioning). In ISO 187 (1990), the preferred climate for paper testing is specified as 23 °C and 50% relative humidity. In the following the most relevant test methods for paper and board testing -will be described. 

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