1 Scope
This standard specifies the terms and definitions, symbols and abbreviations of HEPA and ULPA filter mediums and filter efficiency and resistance test, the selection of test methods, the performance test methods of HEPA and ULPA, and the performance test methods of HEPA and ULPA filter mediums.
This standard is applicable to the test of HEPA and ULPA filter mediums used to filter aerosols and the efficiency and resistance of filters, and may serve as a reference for the efficiency and resistance test of HEPA and ULPA filter mediums and filters.
2 Normative references
The following documents are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 1236 Industrial fans—Performance testing using standardized airways
GB/T 2624.2 Measurement of fluid flow by means of pressure differential devices inserted in circular cross-section conduits running full—Part 2: Orifice plates
GB/T 2624.3 Measurement of fluid flow by means of pressure differential devices inserted in circular cross-section conduits running full—Part 3: Nozzles and Venturi nozzles
GB 11120 Lubricating oils for turbines
GB/T 12564 Generic specification for photomultiplier tubes
GB/T 13554 High efficiency particulate air filter
GB/T 14295 Air filter
GB 50243 Code of acceptance for construction quality of ventilation and air conditioning works
JJF 1190 Calibration specification for airborne particle counter
JJG 172 Tilting tube micromanometers
JJG 875 Digital pressure gauges
3 Terms, definitions and abbreviations
3.1 Terms and definitions
For the purposes of this standard, the terms and definitions given in GB/T 13554 and the following apply.
3.1.1
penetration
ratio of the aerosol concentration after filtration of the filter element to the aerosol concentration before filtration when the filter element is tested
3.1.2
efficiency
ratio of the amount of aerosol filtered by the filter element to the amount of aerosol before filtration when the filter element is tested
3.1.3
rated air flowrate
technical parameter identifying the working capacity of a filter, indicating the maximum air volume flow per unit time to ensure the efficiency of the filter
Note: It is provided by filter manufacturer.
3.1.4
resistance
static pressure difference before and after the filter element under certain test wind speed or air flowrate. For the filter, it is the static pressure difference before and after the filter under rated air flowrate
3.1.5
filter medium
unfolded flat filter material for filtering aerosols
3.1.6
high efficiency particulate air filter; HEPA
air filter used for air filtration and tested by the counting method specified in this standard, and the filtration efficiency without static elimination treatment and after static elimination treatment under rated air flowrate is not less than 99.95%
3.1.7
ultra low penetration air filter; ULPA
air filter used for air filtration and tested by the counting method specified in this standard, and the filtration efficiency without static elimination treatment and after static elimination treatment under rated air flowrate is not less than 99.999%
3.1.8
HEPA filter medium
filter medium for making high efficiency particulate air filter
3.1.9
ULPA filter medium
filter medium for making ultra low penetration air filter
3.1.10
aerosol generator
device for generating standard aerosol for test
3.1.11
particle number concentration
number of particles in the measured particle size range per unit volume of gas (air)
3.1.12
particle size
nominal diameter of a particle measured by some measurement method (optical or aerodynamic equivalent test)
3.1.13
particle size efficiency
filtration efficiency of a filter element for particles of a certain particle size
3.1.14
most penetrating particle size; MPPS
particle size corresponding to the lowest point of the sizing efficiency curve of the tested filter element when the test is carried out according to the counting method specified in this standard
3.1.15
minimum filter efficiency
filtration efficiency of the tested filter element for the most penetrating particle size under given operating conditions, generally known as MPPS efficiency
3.1.16
median particle diameter
corresponding particle size value when the cumulative distribution of aerosol particle size accounts for 50% of the total amount, which is generally expressed by count median particle diameter and mass median particle diameter
3.1.17
sampling flow rate
volume flow rate of air sampled by the measuring element of the test instrument when measuring the particle concentration upstream or downstream of the filter element
3.1.18
sampling duration
effective time of air sampling upstream or downstream of the tested high efficiency particulate air filter element at the sampling volume flow rate
3.1.19
coincide error
error caused by the presence of multiple particles in the scattering cavity of a particle counter at a given time
Note: The coincide error will lead to low count concentration and high average particle size in the measurement results.
3.1.20
monodisperse aerosol
aerosol with a geometric standard deviation of particle size is less than 1.15 (σg < 1.15) when described by distribution equation
3.1.21
quasi-monodisperse aerosol
aerosol with a geometric standard deviation of particle size is not less than 1.15 and not greater than 1.50 (1.15 ≤ σg ≤ 1.50) when described by distribution equation
3.1.22
polydisperse aerosol
aerosol with a geometric standard deviation of particle size is greater than 1.50 (σg>1.50) when described by distribution equation
3.1.23
sodium flame method
method for calculating the mass efficiency of filter elements by testing the mass concentration upstream and downstream of filter elements with sodium flame photometer in case of polydispersed NaCl aerosol. For filter medium and filter tests, the counting peak diameter of test aerosol particles is (0.09 ± 0.02) μm, and the geometric standard deviation of counting shall not be greater than 1.90
3.1.24
oil mist method
method for calculating the mass efficiency of the filter element by testing the mass concentration upstream and downstream of the filter element with an oil mist meter in case of polydispersed liquid aerosols with an average mass diameter of 0.28 μm to 0.34 μm
3.1.25
particle counting method with quasi-monodisperse aerosol
method for calculating the counting efficiency of the filter medium by testing the counting concentration upstream and downstream of the filter medium with condensation particle counter (CPC) or optical particle counter (OPC) in case of quasi-monodisperse aerosols (such as solid particle NaCl or liquid particle DEHS, etc.) with counting median diameter of particles of 0.10 μm to 0.30 μm and the geometric standard deviation of not greater than 1.50
3.1.26
particle counting method with monodisperse aerosol
method for calculating the counting efficiency of filter elements by testing the counting concentration upstream and downstream of filter elements with condensation particle counter (CPC) in case of monodisperse aerosol. Monodisperse aerosol can be generated by several methods, such as differential mobility analyser (DMA), diffusion battery, evaporation and condensation method, polystyrene latex spheres (PSL), etc.
3.1.27
particle counting method with polydisperse aerosol
method for calculating the counting efficiency of filter elements by testing the counting concentration upstream and downstream of filter elements with optical particle counter (OPC) in case of polydisperse aerosol
3.1.28
correlation ratio
ratio of particle concentrations in upstream and downstream sampling systems when the test system is not equipped with a tested filter and keeps a stable aerosol concentration
Note: When an optical particle counter (OPC) is used in the test system to test the aerosol concentration in the upstream and downstream of the tested filter in sequence, the correlation ratio indicates the difference between the upstream and downstream sampling systems due to the particle loss in the upstream and downstream sampling pipelines, the dilution ratio of the diluent (if the upstream sampling adopts the diluent) and the difference between the upstream and downstream sampling duration; when two optical particle counters (OPC) are used respectively in the test system to test the upstream and downstream aerosol concentration of the tested filter, the correlation ratio indicates the difference caused by the different sampling flow rate and counting efficiency of the upstream and downstream sampling counters.
3.2 Abbreviations
For the purposes of this document, the following abbreviations apply.
CPC: Condensation particle counter
DEHS: [sebacic acid-bis (2-ethyl-) ester (commonly known as di-ethyl-hexyl-sebacate)]
DMA: Differential mobility analyser
MPPS: Most penetrating particle size
OPC: Optical particle counter
PAO: Poly alpha olefin
PSL: Polystyrene latex spheres
HEPA: High efficiency particulate air filter
ULPA: Ultra low penetration air filter
Foreword i
1 Scope
2 Normative references
3 Terms, definitions and abbreviations
4 Selection of test methods
5 Performance device and test method of HEPA and ULPA
6 Performance test method of HEPA and ULPA filter mediums
Annex A (Normative) Structure and maintenance of filter performance test device by sodium flame method
Annex B (Informative) Structure diagram of components of filter and filter medium test devices by sodium flame method
Annex C (Normative) Structure and maintenance of filter test device by oil mist method
Annex D (Normative) Correction, calibration and maintenance of filter medium test device by oil mist method
Annex E (Normative) Vaporization-condensation oil mist generator in filter test device by oil mist method
Annex F (Normative) Oil mist meter
Annex G (Normative) Structure and maintenance of filter medium test device by sodium flame method
Annex H (Normative) Oil mist generator in the filter medium test device
1 Scope
This standard specifies the terms and definitions, symbols and abbreviations of HEPA and ULPA filter mediums and filter efficiency and resistance test, the selection of test methods, the performance test methods of HEPA and ULPA, and the performance test methods of HEPA and ULPA filter mediums.
This standard is applicable to the test of HEPA and ULPA filter mediums used to filter aerosols and the efficiency and resistance of filters, and may serve as a reference for the efficiency and resistance test of HEPA and ULPA filter mediums and filters.
2 Normative references
The following documents are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 1236 Industrial fans—Performance testing using standardized airways
GB/T 2624.2 Measurement of fluid flow by means of pressure differential devices inserted in circular cross-section conduits running full—Part 2: Orifice plates
GB/T 2624.3 Measurement of fluid flow by means of pressure differential devices inserted in circular cross-section conduits running full—Part 3: Nozzles and Venturi nozzles
GB 11120 Lubricating oils for turbines
GB/T 12564 Generic specification for photomultiplier tubes
GB/T 13554 High efficiency particulate air filter
GB/T 14295 Air filter
GB 50243 Code of acceptance for construction quality of ventilation and air conditioning works
JJF 1190 Calibration specification for airborne particle counter
JJG 172 Tilting tube micromanometers
JJG 875 Digital pressure gauges
3 Terms, definitions and abbreviations
3.1 Terms and definitions
For the purposes of this standard, the terms and definitions given in GB/T 13554 and the following apply.
3.1.1
penetration
ratio of the aerosol concentration after filtration of the filter element to the aerosol concentration before filtration when the filter element is tested
3.1.2
efficiency
ratio of the amount of aerosol filtered by the filter element to the amount of aerosol before filtration when the filter element is tested
3.1.3
rated air flowrate
technical parameter identifying the working capacity of a filter, indicating the maximum air volume flow per unit time to ensure the efficiency of the filter
Note: It is provided by filter manufacturer.
3.1.4
resistance
static pressure difference before and after the filter element under certain test wind speed or air flowrate. For the filter, it is the static pressure difference before and after the filter under rated air flowrate
3.1.5
filter medium
unfolded flat filter material for filtering aerosols
3.1.6
high efficiency particulate air filter; HEPA
air filter used for air filtration and tested by the counting method specified in this standard, and the filtration efficiency without static elimination treatment and after static elimination treatment under rated air flowrate is not less than 99.95%
3.1.7
ultra low penetration air filter; ULPA
air filter used for air filtration and tested by the counting method specified in this standard, and the filtration efficiency without static elimination treatment and after static elimination treatment under rated air flowrate is not less than 99.999%
3.1.8
HEPA filter medium
filter medium for making high efficiency particulate air filter
3.1.9
ULPA filter medium
filter medium for making ultra low penetration air filter
3.1.10
aerosol generator
device for generating standard aerosol for test
3.1.11
particle number concentration
number of particles in the measured particle size range per unit volume of gas (air)
3.1.12
particle size
nominal diameter of a particle measured by some measurement method (optical or aerodynamic equivalent test)
3.1.13
particle size efficiency
filtration efficiency of a filter element for particles of a certain particle size
3.1.14
most penetrating particle size; MPPS
particle size corresponding to the lowest point of the sizing efficiency curve of the tested filter element when the test is carried out according to the counting method specified in this standard
3.1.15
minimum filter efficiency
filtration efficiency of the tested filter element for the most penetrating particle size under given operating conditions, generally known as MPPS efficiency
3.1.16
median particle diameter
corresponding particle size value when the cumulative distribution of aerosol particle size accounts for 50% of the total amount, which is generally expressed by count median particle diameter and mass median particle diameter
3.1.17
sampling flow rate
volume flow rate of air sampled by the measuring element of the test instrument when measuring the particle concentration upstream or downstream of the filter element
3.1.18
sampling duration
effective time of air sampling upstream or downstream of the tested high efficiency particulate air filter element at the sampling volume flow rate
3.1.19
coincide error
error caused by the presence of multiple particles in the scattering cavity of a particle counter at a given time
Note: The coincide error will lead to low count concentration and high average particle size in the measurement results.
3.1.20
monodisperse aerosol
aerosol with a geometric standard deviation of particle size is less than 1.15 (σg < 1.15) when described by distribution equation
3.1.21
quasi-monodisperse aerosol
aerosol with a geometric standard deviation of particle size is not less than 1.15 and not greater than 1.50 (1.15 ≤ σg ≤ 1.50) when described by distribution equation
3.1.22
polydisperse aerosol
aerosol with a geometric standard deviation of particle size is greater than 1.50 (σg>1.50) when described by distribution equation
3.1.23
sodium flame method
method for calculating the mass efficiency of filter elements by testing the mass concentration upstream and downstream of filter elements with sodium flame photometer in case of polydispersed NaCl aerosol. For filter medium and filter tests, the counting peak diameter of test aerosol particles is (0.09 ± 0.02) μm, and the geometric standard deviation of counting shall not be greater than 1.90
3.1.24
oil mist method
method for calculating the mass efficiency of the filter element by testing the mass concentration upstream and downstream of the filter element with an oil mist meter in case of polydispersed liquid aerosols with an average mass diameter of 0.28 μm to 0.34 μm
3.1.25
particle counting method with quasi-monodisperse aerosol
method for calculating the counting efficiency of the filter medium by testing the counting concentration upstream and downstream of the filter medium with condensation particle counter (CPC) or optical particle counter (OPC) in case of quasi-monodisperse aerosols (such as solid particle NaCl or liquid particle DEHS, etc.) with counting median diameter of particles of 0.10 μm to 0.30 μm and the geometric standard deviation of not greater than 1.50
3.1.26
particle counting method with monodisperse aerosol
method for calculating the counting efficiency of filter elements by testing the counting concentration upstream and downstream of filter elements with condensation particle counter (CPC) in case of monodisperse aerosol. Monodisperse aerosol can be generated by several methods, such as differential mobility analyser (DMA), diffusion battery, evaporation and condensation method, polystyrene latex spheres (PSL), etc.
3.1.27
particle counting method with polydisperse aerosol
method for calculating the counting efficiency of filter elements by testing the counting concentration upstream and downstream of filter elements with optical particle counter (OPC) in case of polydisperse aerosol
3.1.28
correlation ratio
ratio of particle concentrations in upstream and downstream sampling systems when the test system is not equipped with a tested filter and keeps a stable aerosol concentration
Note: When an optical particle counter (OPC) is used in the test system to test the aerosol concentration in the upstream and downstream of the tested filter in sequence, the correlation ratio indicates the difference between the upstream and downstream sampling systems due to the particle loss in the upstream and downstream sampling pipelines, the dilution ratio of the diluent (if the upstream sampling adopts the diluent) and the difference between the upstream and downstream sampling duration; when two optical particle counters (OPC) are used respectively in the test system to test the upstream and downstream aerosol concentration of the tested filter, the correlation ratio indicates the difference caused by the different sampling flow rate and counting efficiency of the upstream and downstream sampling counters.
3.2 Abbreviations
For the purposes of this document, the following abbreviations apply.
CPC: Condensation particle counter
DEHS: [sebacic acid-bis (2-ethyl-) ester (commonly known as di-ethyl-hexyl-sebacate)]
DMA: Differential mobility analyser
MPPS: Most penetrating particle size
OPC: Optical particle counter
PAO: Poly alpha olefin
PSL: Polystyrene latex spheres
HEPA: High efficiency particulate air filter
ULPA: Ultra low penetration air filter
Contents of GB/T 6165-2021
Foreword i
1 Scope
2 Normative references
3 Terms, definitions and abbreviations
4 Selection of test methods
5 Performance device and test method of HEPA and ULPA
6 Performance test method of HEPA and ULPA filter mediums
Annex A (Normative) Structure and maintenance of filter performance test device by sodium flame method
Annex B (Informative) Structure diagram of components of filter and filter medium test devices by sodium flame method
Annex C (Normative) Structure and maintenance of filter test device by oil mist method
Annex D (Normative) Correction, calibration and maintenance of filter medium test device by oil mist method
Annex E (Normative) Vaporization-condensation oil mist generator in filter test device by oil mist method
Annex F (Normative) Oil mist meter
Annex G (Normative) Structure and maintenance of filter medium test device by sodium flame method
Annex H (Normative) Oil mist generator in the filter medium test device