Page 57 - MASHRAE 35th Anniversary

ASHRAE 52.2:2017 requires the air filter to design with minimum final resistance for the air filter shall be the same as or greater than twice the initial pressure (ASHRAE,2017). In another clause, ASHRAE 52.2:2017 requires the air filter to test airflow in order to withstand 350Pa final resistance. ASHRAE 52.2: 2017 will lead the manufacturer to produce more rigid filters to withstand higher pressure compared with ISO16890:2016.
Conclusion
ASHRAE 52.2:2017 only uses single aerosol potassium chloride to generate the particles with size range of 0.3 to 10.0􏰀m. ISO 16890:2016 uses 2 types of aerosols which are diethylhexylsebacate to generate the particles 0.3 to 1.0􏰀m and potassium chloride to generate particle s1.0 to 10.0􏰀m. Using 2 types of aerosols does not bring significant benefits to the filter testing but it will bring more process to the testing procedure. Besides that, diethylhexylsebacate will increase the difficulty of duct maintenance. ISO16890 will allow the manufacturer to use any type of aerosol that matches the standards criteria. This flexibility may create non consistent results that confuse the industry.
. ISO16890:2016 introduced 49 grades while ASHRAE 52.2 only has 16 grades. The highest grade air filter of these 2 standards is the same which requires 95% particle removal efficiency on 0.3-1.0􏰀m particles. Multiple filter efficiency grades benefit the user but increase costs to the manufacturer and supplier. Manufacturers and suppliers are required to keep a higher inventory on the filter or filter media and this will directly impact filter costs. In ISO16890:2016, manufacturers who wish to provide a full range of air filters, are required to run a multiple of tests which will indirectly increase the operation cost of the manufacturer. In the end, users have to pay more to get the same quality of the clean air.
ISO16890:2016 set the test room temperature at 23±5°C. This can reduce the fluctuation of the particle activeness on Brownian motion. 23±5°C temperature range is within a human acceptable temperature range, and also similar to normal indoor temperature range. ASHRAE 52.2:2017 requires the test room temperature to be at 10-38°C, 10°C test room temperature test report might not be practical for tropical countries as reference.
ISO16890:2016 requires the air filter final pressure to be at 300Pa, while ASHREA 52.2:2017 required it at 350Pa. ASHRAE will direct the manufacturer to produce
a more rigid filter. This is beneficial to the user because the filter will have a longer life span.
Overall, both of the standards have their pros and cons. ISO16890:2017 introduced a brand new air filter efficiency classification which provides a better understanding for the user. ASHRAE 52.2:2017 only using single test aerosol that provide more precise result. ISO16890:2017 required ePM1 and ePM2.5 to do the passive electrostatic discharge which leads the manufacturer towards non passive electrostatic charge air filter will discourage the research in passive electrostatic technology in the future.
REFERENCES
B. Zhou, J.M Shen, (Zhou,2007), Comparison of General Ventilation Air Filter Test Standards between America and Europe, ReserchGate.
B. Stephens, (Stephens,2018), Evaluating the Sensitivity of the Mass-Based Particle Removal Calculations for HVAC Filters in ISO 16890 to Assumptions for Aerosol Distributions, Atmosphere 2018, 9, 8.
International Organization for Standardization (ISO,2016) ISO 16890-1:2016- Air Filters for General Ventilation – Part 1: Technical specifications, Requirements and Classification) System based upon Particulate Matter Efficiency (ePM).
International Organization for Standardization (ISO,2016) ISO 16890-1:2016- 2016 Air Filters for General Ventilation – Part 2: Measurement of Fractional Efficiency and Air Flow Resistance.
International Organization for Standardization (ISO,2016) ISO 16890-1:2016- Air Filters for General Ventilation – Part 3: Determination of the Gravimetric Efficiency and the Air Flow Resistance versus the Mass of Test Dust Captured.
International Organization for Standardization (ISO,2016) ISO 16890-1:2016- Air Filters for General Ventilation – Part 4: Conditioning Method to Determine the Minimum Fractional Test Efficiency,
ANSI/ASHRAE (ASHRAE,2017) ASHRAE 52.2:2017, Method of Testing General ventilation Air- Cleaning Devices for Removal Efficiency by Particle Size,
M. Hartley, K. Archuleta, (Hartley,2011) Critical Cleaning Agents for Di-2-ethylhexyl Sebacate, U.S. De􏰁a􏰂􏰃men􏰃 􏰄f Ene􏰂g􏰅􏰆􏰇 Na􏰃i􏰄nal N􏰈clea􏰂 Sec􏰈􏰂i􏰃􏰅 Administration.
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