T/CRAAS 439.2-2022 General Ventilation Filter - Part 2: Measurement of Air Flow Efficiency and Resistance

Scope

Main technical content: This part of the T/CRAAS 439 series standard specifies the aerosol generation, test instruments, and test methods for general ventilation filters in terms of their filtration efficiency and resistance. This standard needs to be used in conjunction with T/CRAAS 439.1, T/CRAAS 439.3, and T/CRAAS 439.4. The test methods specified in this standard are applicable to filters with an airflow rate of 0.25 m3/s to 1.5 m3/s (900 m3/h to 5,400 m3/h) and a nominal cross-section of 610 mm × 610 mm. The T/CRAAS 439 standard (all parts) applies to general ventilation filters that meet the test procedures specified in the T/CRAAS 439 series standard and have an ePM1 filtration efficiency no higher than 99% and an ePM10 filtration efficiency no lower than 20%. Note: The lower limit of the ePM10 filtration efficiency specified for the filters applicable to this standard is 20%, because the test results obtained under this standard may not meet the statistical validity requirements when the efficiency is lower than this value. For the determination of the filtration efficiency of filters for other particle sizes, see T/CRAA 431. This standard is not applicable to filters used in portable indoor air purifiers. The filtration performance test results obtained according to this series of standards cannot be used to quantitatively predict the filtration efficiency and service life of the tested filters under actual operating conditions.

Development Information

Same series standard

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