JJG (Light Industry) 69-2000 "paper Gurley Porosity Meter (Trial) verification procedure" is applicable to Gurley Porosity Meter with Porosity Measurement range of 1.0 × 10 ^ -1 μm/(Pa · s) to 1.0 × 10 ^ 2 μm/(Pa · s). The procedure specifies the method of verification of Porosity Meter, including initial verification, subsequent verification and verification in use. The content covers the performance requirements, technical specifications, verification conditions and methods of the instrument. The Porosity Meter is required to meet specific standards for Appearance, Sealing, Operating system function and Measurement accuracy during verification. After the verification, the instrument will issue a verification certificate, and those who fail will receive a notice and point out the unqualified items. The verification period is generally one year.