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GB/T 6165-2021: Test method of the performance of high efficiency particulate air filter - Efficiency and resistance
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Test method of the performance of high efficiency particulate air filter - Efficiency and resistance
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Test method of the performance of high efficiency particulate air filter -- Efficiency and resistance
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Methods for testing the performance of high efficiency particulate air filter--Penetration and resistance
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Basic data | Standard ID | GB/T 6165-2021 (GB/T6165-2021) | | Description (Translated English) | Test method of the performance of high efficiency particulate air filter - Efficiency and resistance | | Sector / Industry | National Standard (Recommended) | | Classification of Chinese Standard | Q76 | | Word Count Estimation | 52,590 | | Issuing agency(ies) | State Administration for Market Regulation, China National Standardization Administration | GB/T 6165-2021: Test method of the performance of high efficiency particulate air filter - Efficiency and resistance
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(High efficiency air filter performance test method efficiency and resistance)
ICS 91.140.30
Q76
National Standards of People's Republic of China
Replace GB/T 6165-2008
High efficiency air filter performance test method
Efficiency and resistance
Released on 2021-04-30
2021-11-01 implementation
State Administration of Market Supervision and Administration
Issued by the National Standardization Management Committee
Table of contents
Foreword Ⅲ
1 Scope 1
2 Normative references 1
3 Terms and definitions, abbreviations 1
4 Choice of test method 4
5 Performance devices and test methods of high-efficiency and ultra-high-efficiency air filters 4
6 Test methods for performance of high-efficiency and ultra-efficient filter media 17
Appendix A (Normative Appendix) The structure and maintenance of the sodium flame filter performance test device 28
Appendix B (informative appendix) Sodium flame method filter and filter material test device component structure diagram 33
Appendix C (Normative Appendix) Construction and Maintenance of Oil Mist Filter Test Device 36
Appendix D (Normative Appendix) Proofreading, Calibration and Maintenance of Oil Mist Filter Test Device 39
Appendix E (Normative Appendix) Vaporization-condensation type oil mist generator in the oil mist filter test device 41
Appendix F (Normative Appendix) Oil mist meter 44
Appendix G (Normative Appendix) Structure and Maintenance of Sodium Flame Filter Material Test Device 45
Appendix H (Normative Appendix) Oil mist generator in filter material test device 47
High efficiency air filter performance test method
Efficiency and resistance
1 Scope
This standard specifies the terms, definitions, symbols and abbreviations for high-efficiency, ultra-high-efficiency filter media and filter efficiency and resistance testing, and the test method
Selection, high-efficiency and ultra-efficient air filter performance test methods, high-efficiency and ultra-efficient filter material performance test methods, etc.
This standard applies to the detection of efficiency and resistance of high-efficiency and ultra-high-efficiency filter materials and filters used in filtering aerosols. Sub-high efficiency filter material and
The efficiency and resistance of the filter can be tested by reference.
2 Normative references
The following documents are indispensable for the application of this document. For dated reference documents, only the dated version applies to this article
Pieces. For undated reference documents, the latest version (including all amendments) is applicable to this document.
GB/T 1236 Standardized air duct performance test for industrial ventilators
GB/T 2624.2 Use a differential pressure device installed in a circular cross-section pipe to measure the flow of fluid in a full pipe. Part 2.Orifice plate
GB/T 2624.3 Use a differential pressure device installed in a circular cross-section pipe to measure the flow of fluid in a full pipe. Part 3.Nozzle and Venturi
Inside nozzle
GB 11120 turbine oil
GB/T 12564 General Specification for Photomultiplier Tubes
GB/T 13554 high efficiency air filter
GB/T 14295 air filter
GB 50243 Code for acceptance of construction quality of ventilation and air-conditioning engineering
JJF1190 Dust Particle Counter Calibration Specification
JJG172 Inclined Micro Manometer
JJG875 Digital Pressure Gauge Verification Regulation
3 Terms and definitions, abbreviations
3.1 Terms and definitions
The following terms and definitions defined in GB/T 13554 apply to this document.
3.1.1
Penetration
When testing the filter element, the ratio of the aerosol concentration after the filter element is filtered to the aerosol concentration before the filter.
3.1.2
Efficiency
When testing the filter element, the ratio of the amount of aerosol filtered by the filter element to the amount of aerosol before filtration.
3.1.3
Rated airflow rate
The technical parameters that identify the working capacity of the filter indicate the maximum air volume flow per unit time that guarantees the efficiency of the filter.
Note. Provided by the filter manufacturer.
3.1.4
Resistance
Under certain test wind speed or air volume conditions, the static pressure difference before and after the filter element. For the filter, it is before and after the filter at the rated air volume
The static pressure difference.
3.1.5
Filtermedium
Unfolded flat filter material used to filter aerosols.
3.1.6
High efficiency air filter highefficiencyparticulateairfilter;HEPA
For air filtration and use the counting method specified in this standard for testing, the filtration efficiency and
Air filters whose filtration efficiency after antistatic treatment is not less than 99.95%.
3.1.7
Ultra high efficiency air filter ultralowpenetrationairfilter; ULPA
For air filtration and use the counting method specified in this standard for testing, the filtration efficiency and
Air filters whose filtration efficiency after antistatic treatment is not less than 99.999%.
3.1.8
High efficiency filter medium HEPAfiltermedium
Used to make the filter material of high efficiency air filter.
3.1.9
ULPAfiltermedium
Used to make the filter material of ultra-high efficiency air filter.
3.1.10
Aerosolgenerator
A device used to produce standard aerosols for testing.
3.1.11
Particle count concentration particlenumberconcentration
The number of particles within the range of the measured particle size per unit volume of gas (air).
3.1.12
Particlesize
The nominal diameter of the particle measured by a certain method (optical or aerodynamic equivalent test).
3.1.13
Diameter counting efficiency particlessizeefficiency
The filtration efficiency of the filter element for particles of a certain size.
3.1.14
Most penetrating particle size; MPPS
When the test is carried out according to the counting method specified in this standard, the particle size corresponding to the lowest point of the diameter measurement efficiency curve of the tested filter element.
3.1.15
Minimumfilterefficiency
Under given operating conditions, the filtration efficiency of the tested filter element for the most easily permeable particle size particles is generally called MPPS efficiency.
3.1.16
Median particle diameter
When the cumulative distribution of aerosol particle size accounts for 50% of the total, the corresponding particle size is usually expressed by counting median diameter and mass median diameter.
3.1.17
Samplingflowrate
When the detection instrument measures the particle concentration upstream or downstream of the filter element, it measures the air volume flow rate sampled by the element.
3.1.18
Samplingduration
Under the sampling volume flow, the effective time of air sampling upstream or downstream of the tested high efficiency air filter element.
3.1.19
Coincidence error
In a given time, the error caused by the scattering cavity of the particle counter contains multiple particles.
Note. The coincidence error will lead to low count concentration and high average particle size in the measurement results.
3.1.20
Monodisperse aerosol monodisperseaerosol
When described by the distribution equation, the geometric standard deviation of the particle size is less than 1.15 (σg< 1.15).
3.1.21
Quasi-monodisperse aerosol quasi-monodisperseaerosol
When described by the distribution equation, the geometric standard deviation of the particle size is greater than or equal to 1.15 and less than or equal to 1.50, that is (1.15≤σg≤1.50)
Aerosol.
3.1.22
Polydisperseaerosol
When described by the distribution equation, the geometric standard deviation of the particle size is greater than 1.50 (σg >1.50).
3.1.23
Sodium flame method
A polydisperse NaCl aerosol is generated, and the mass concentration of the upstream and downstream of the filter element is detected with a sodium flame photometer, and the quality of the filter element is calculated
effectiveness. For the filter material and filter test, the peak diameter of the test aerosol particles is (0.09±0.02) μm, and the counting geometry standard is (0.09±0.02) μm.
The standard deviation is not more than 1.90.
3.1.24
Oilmistmethod
A polydisperse liquid aerosol occurs, and the average particle diameter is 0.28μm~0.34μm. Use an oil mist meter to detect the upper and lower parts of the filter element.
The mass concentration of the swimming pool is used to calculate the mass efficiency of the filter element.
3.1.25
Quasi-monodisperse aerosol counting method particlecountingmethodwithquasi-monodisperseaerosol
Quasi-monodisperse aerosols (such as solid particles NaCl or liquid particles DEHS, etc.) occur, and the median diameter of the particles is 0.10 μm~
Between 0.30μm, the geometric standard deviation is not more than 1.50, use condensation nucleus particle counter (CPC) or optical particle counter (OPC) to detect
Calculate the counting efficiency of the filter material by counting the concentration of the upstream and downstream of the filter material.
3.1.26
Monodisperse aerosol counting method particlecountingmethodwithmonodisperseaerosol
Monodisperse aerosol is generated, and the condensation nucleus particle counter (CPC) is used to detect the counting concentration of the upstream and downstream of the filter element, and calculate the filter element
Counting efficiency of pieces. There are many ways to generate monodisperse aerosols, such as differential electromigration analyzer (DMA), diffusion battery pack, evaporation
Condensation method, polystyrene latex ball (PSL), etc.
3.1.27
Polydisperse aerosol counting method particlecountingmethodwithpolydisperseaerosol
Polydisperse aerosols (such as solid particles of NaCl or liquid particles of DEHS, etc.) have been detected using an optical particle counter (OPC)
The counting concentration of the upstream and downstream of the filter element is used to calculate the counting efficiency of the filter element.
3.1.28
Correlation coefficient
The ratio of the particle concentration in the upstream and downstream sampling systems when the test system is not equipped with the tested filter and maintains a stable aerosol concentration.
Note. When the test system uses an optical particle counter (OPC) to detect the upstream and downstream aerosol concentrations of the tested filter in turn, the correlation coefficient table
Shows that due to the particle loss of the upstream and downstream sampling pipelines, the dilution ratio of the diluter (if the upstream sampling adopts a diluter), and the difference between the upstream and downstream sampling time
The difference between the upstream and downstream sampling systems caused by the test system; when the test system samples two optical particle counters (OPC) respectively for the upstream and downstream gas dissolution of the tested filter
When the glue concentration is detected, the correlation coefficient represents the difference caused by the sampling flow rate and counting efficiency of the upstream and downstream sampling counters.
3.2 Abbreviations
The following abbreviations apply to this document.
4 Choice of test method
4.1 This standard gives three test methods. counting method, sodium flame method, and oil mist method. The reference method is counting method.
4.2 For high-efficiency air filters and filter materials, any of the three methods can be used for efficiency testing according to requirements, but they should be noted at the same time.
State the test methods and test results. In the production and testing of high-efficiency filter media, it is advisable to use sodium flame under the conditions of a clear comparison with the benchmark method.
Fast test methods such as method and quasi-monodisperse aerosol counting method.
4.3 For ultra-high efficiency air filters and filter materials, the counting method should be used for efficiency testing. In the production and testing of ultra-high efficiency filter materials, it is appropriate to
Under the condition of a clear comparison with the benchmark method, rapid test methods such as the quasi-monodisperse aerosol counting method are used.
4.4 For filters and filter media with MPPS not greater than 0.1μm, the benchmark method is the monodisperse aerosol counting method. Filter out in this category
In the factory inspection, the counting method can be used to test the particles in the range of 0.1μm~0.2μm under the condition of clear comparison with the reference method.
And according to the comparison with the benchmark method to revise the test results.
5 Performance devices and test methods of high-efficiency and ultra-high-efficiency air filters
5.1 Requirements for test equipment
5.1.1 Fan
5.1.1.1 Air volume
The air volume should be calculated as 1.3 times the maximum air volume of the tested filter.
5.1.1.2 Wind pressure
The wind pressure should include at least the sum of the following items.
a) Air duct resistance (taken as 1.2 times the calculated resistance);
b) The resistance of the air inlet filter (taken as 2 times the initial resistance);
c) The maximum resistance of the tested filter;
d) Resistance of the air volume measuring device;
e) For the sodium flame method test device, the positive pressure value required for sampling after the filter should be considered (not less than 600Pa).
5.1.1.3 Air volume stability
During the test, the air volume of the test device should be stable within ±2% of the set value.
5.1.2 Air duct
5.1.2.1 Materials
The sodium flame method test device should be made of polyvinyl chloride plastic or other corrosion-resistant materials from the spray box to the buffer box; the other of the sodium flame method test device
Stainless steel air ducts should be used for the remaining part and other test devices. The wall thickness of the duct should not be less than 1mm. When necessary, the air duct should be grounded and
Rot treatment.
5.1.2.2 Dimensions of the front and rear pipe sections of the air volume measuring device
When a standard orifice plate is used, the size of the front and rear pipe sections should be designed in accordance with the relevant requirements of GB/T 2624.2; when the standard nozzle is used
At the time, the front and rear pipe section dimensions should be designed in accordance with the relevant requirements of GB/T 2624.3.
5.1.2.3 Angle of the test filter connecting pipe
The included angle of the diffusion section of the test filter connecting pipe should not be greater than 14°, and the included angle of the convergent section should not be greater than 30°, and should meet GB/T 1236
Related requirements.
5.1.2.4 Air duct tightness
The production, installation and inspection of the air duct in the test device shall meet the relevant requirements of GB 50243 for medium pressure systems, and the joints of the air duct shall be adopted
welding. The air duct tightness should be suppressed and leak tested under a pressure of 2kPa, and the air leakage should not be greater than 1.64m3/(h·m2).
5.1.3 Air inlet filter
5.1.3.1 Pre-filter
The pre-filter should meet the relevant requirements of GB/T 14295 medium-efficiency filter.
5.1.3.2 High efficiency air filter
The high efficiency air filter should meet the relevant requirements of GB/T 13554.When a heater is provided upstream of the filter, the temperature resistance of the filter should not be low
At 60°C.
5.1.4 Wind speed uniformity of upstream sampling section
Adjust the operating air volume of the test device to the maximum test air volume, and the cross section of the sampling point upstream of the test air duct is according to Figure 1 according to the cross-sectional area of the air duct.
The average distribution shown is 9 measuring points, and the wind speed is tested separately. The deviation between the actual wind speed of each measuring point and the average value of each measuring point should not be large.
Less than 10%.
Fig.1 Schematic diagram of measuring point arrangement for wind speed and aerosol concentration uniformity of upstream sampling section
5.1.5 The uniformity of aerosol concentration in the upstream sampling section
Adjust the operating air volume of the test device to the maximum test air volume, start the aerosol generator and maintain stable operation, and sample upstream of the test air duct
According to the cross-sectional area of the air duct, 9 measuring points are evenly distributed as shown in Figure 1 to test the aerosol concentration. The measured aerosol concentration is measured at each measuring point.
The deviation between the glue concentration and the average value of each measuring point should not be more than 10%.
5.1.6 Stability of upstream aerosol concentration
Adjust the operating air volume of the test device to the maximum test air volume, start the aerosol generator and maintain stable operation, and sample upstream of the test air duct
Sampling is performed at the point, and the fluctuation of the measured aerosol mass concentration or the count concentration within a given particle size range within 30 minutes should not exceed 10%.
5.1.7 General test equipment requirements
The air volume test device can use standard orifice plates or nozzles, and is designed and installed in accordance with the relevant requirements of GB/T 2624.2 and GB/T 2624.3.
Installation, use and calibration, and should meet the following requirements.
a) The pressure test device used for the filter resistance and the pressure difference measurement of the flow measurement device, the accuracy should not be less than 2Pa, and should be based on the selected
Depending on the pressure test device, the verification and calibration shall be carried out regularly according to the relevant requirements of JJG172 or JJG875.
b) The counter should be periodically verified and calibrated according to the relevant requirements of JJF1190.The photoelectric measuring instrument in the sodium flame photometer should be
According to the relevant requirements of GB/T 12564, the stability test and calibration are carried out regularly. The oil mist meter should be carried out in accordance with the requirements of 5.4.3.1.1.4
Calibration.
5.1.8 Upstream and downstream sampling correlation coefficient
When the aerosol generator is working stably, the filter is not installed in the test section, and the diluter is not installed in the upstream sampling section, the correlation coefficient of each particle size block
It should be 1.00 ± 0.03.After installing the diluter in the upstream sampling section, the correlation coefficient of each particle size block should be tested and confirmed regularly.
5.1.9 Resistance standard
5.1.9.1 Use orifice plates with known resistance (or other resistance standards) to conduct periodic tests according to 5.2.4.2.4.
5.1.9.2 The resistance standard should be properly stored and kept when not in use to prevent damage.
5.1.9.3 The test of resistance standard parts shall meet the following requirements.
a) At least 4 air volume status points should be selected for testing within the air volume range of the test device.
b) During each test, the deviation between the resistance test results at each air volume state point and the calibration value should not be more than 3%. If the resistance standard
If the deviation between the test resistance value and the calibration value is greater than 3%, the necessary measures should be taken for the tightness of the pipeline, the pressure gauge of the flow test device, etc.
Inspection, maintenance and calibration.
c) The resistance standard and the reference test device can be used for comparison verification test.
5.1.10 Reference filter
5.1.10.1 The test device should prepare a reference filter with a known efficiency, and perform regular efficiency tests according to the methods specified in 5.2, 5.3 or 5.4.
5.1.10.2 At least two reference filters should be prepared, of which one is the main reference filter and the other is the backup. Reference filter selection
The filter material should not use materials that are difficult to maintain stable filtration efficiency for a long time. The reference filter should be properly stored and kept when not in use to prevent
damaged.
5.1.10.3 The use of the reference filter shall meet the following requirements.
a) The deviation between the efficiency test value of the reference filter and the mantissa of the calibration value (the first non-9 value of the efficiency value) should not exceed ±5.
b) The main reference filter should be selected first during each test. If the deviation between the efficiency test value of the main reference filter and the calibration value exceeds the value of a)
If required, the spare reference filter should be tested. If the standby reference filter efficiency test value meets the requirements of this standard, it shall be
Replace the main reference filter.
c) If the deviation between the efficiency test value and the calibration value of the main reference filter and the backup reference filter exceeds the requirements of a), the test equipment should be tested.
Set up sampling system, aerosol test device, etc. for necessary inspection, calibration and maintenance.
5.1.11 Calibration of test device
The calibration cycle and requirements of the test device are shown in Table 1.
Table 1 Calibration cycle and requirements of test equipment
5.2 Counting method
5.2.1 Test principle
Use an aerosol generator to generate aerosols that meet the test requirements, and use OPC to analyze the 0.1μm~0.3μm particles upstream and downstream of the tested filter.
The particles within the diameter range are detected, and the diameter counting efficiency is calculated. When measuring the upstream aerosol concentration, if the upstream aerosol concentration exceeds the upper OPC
Limit the concentration, the sampling air should be diluted to reduce the coincidence error of OPC counting. The dilution of the sampled air can be achieved by the diluter, or
Realized by the difference of upstream and downstream OPC sampling flow.
5.2.2 Test method
The monodisperse aerosol counting method or the polydisperse aerosol counting method can be selected for efficiency testing. The air duct system of the two methods is the same, only
The aerosol generator and the corresponding detection device are different. When the monodisperse aerosol counting method is used for the test, such as the filter
The filter material has been tested by the monodisperse aerosol counting method and its MPPS has been obtained, then the monodisperse aerosol meter selected in the filter test
The median diameter of the number should be within ±10% of its MPPS. Otherwise, the filter manufacturer should negotiate with the user to determine the test aerosol count
Value diameter range.
5.2.3 Test device
5.2.3.1 Counting method filter performance detection test device is mainly composed of aerosol generator, air duct system, aerosol sampling and detection device group
Schematic diagram of the test device is shown in Figure 2.The test device is allowed to be different, but it should meet the requirements of 5.1, and the test results of the same filter
Should be consistent with the standard test device.
5.2.3.2 The measuring device should use OPC, and the OPC particle size test range should include at least three gears of 0.1μm, 0.2μm, and 0.3μm.
5.2.4 Filter detection
5.2.4.1 Operating parameters
5.2.4.1.1 Test air
An electric heater should be installed in the air duct system to ensure that the temperature in the system is within the range of (23 ± 5) ℃ and the relative humidity is not greater than 75%.
5.2.4.1.2 Test aerosol
The test aerosol should use oily liquid aerosols such as DEHS and PAO generated by spraying. When solid aerosols are used for testing
At the time, the necessary electrostatic neutralization treatment should be carried out, and the reference filter should be used to verify the consistency of the test results with the oily liquid aerosol.
5.2.4.1.3 Spray air pressure
The pressure of the clean compressed air entering the nebulizer should meet the requirements of the aerosol generator.
5.2.4.1.4 Spray air volume
Under the specified pressure, the amount of compressed air entering each sprayer should be constant.
5.2.4.1.5 Upstream aerosol dilution
When OPC measures the aerosol concentration, in most cases, the original aerosol should be diluted, and the dilution factor should be 10 times to 1000 times.
Within the range, the specific value depends on the initial aerosol concentration and the measuring equipment used. It should be ensured that the test aerosol concentration does not exceed the OPC
Maximum saturation concentration.
5.2.4.1.6 Aerosol sampling volume
The aerosol sampling volume is determined by the OPC sampling volume and sampling time, and the downstream aerosol counting concentration should be guaranteed to be statistically significant.
5.2.4.2 Test procedure
5.2.4.2.1 Operation preparation
5.2.4.2.1.1 When the aerosol generator is turned on and there is no test filter in the test device, the upstream and downstream aerosols should be measured respectively.
Count the concentration and calculate the correlation coefficient of upstream and downstream sampling.
5.2.4.2.1.2 Visually inspect the filter material in the tested filter for defects, cracks and holes; check the joints of the filter frame corners
And whether there is a seal between the frame and the filter material, whether there is a gap, whether there is any abnormality in the structure. Filters that pass the visual inspection can be used as
For testing.
5.2.4.2.1.3 Fasten the tested filter on the test section according to the airflow direction indicated by the arrow.
5.2.4.2.2 System startup
5.2.4.2.2.1 Start the fan, adjust the frequency converter of the fan and the valve at the end of the air duct, so that the air volume of the air duct system reaches the test air volume.
5.2.4.2.2.2 The temperature in the regulation system is within the range of (23±5)℃, and the relative humidity is not more than 75%.
5.2.4.2.3 Preliminary inspection
When the aerosol generator and the tested filter are in place, the downstream aerosol count concentration should be tested and the background concentration should be checked.
5.2.4.2.4 Resistance detection
Use a micromanometer to test the resistance of the filter section under the test air volume, and subtract the air resistance of the test section to obtain the filter resistance.
5.2.4.2.5 Start the aerosol generator
Start the aerosol generator, adjust the parameters of the aerosol generator according to the product manual and keep it stable.
5.2.4.2.6 Filter efficiency test
The filter efficiency test should meet the following requirements.
a) The test aerosol should be evenly mixed with the test air. In order to determine the particle size efficiency, 0.1μm~0.2μm and
Perform at least 3 tests on the two-stop particle size range of 0.2μm~0.3μm, and calculate the average value and the filtering efficiency with 95% confidence.
The lower limit of the rate, choose its lower value as the counting method test efficiency of the tested filter.
b) When performing efficiency testing, two OPCs can be used to measure at the same time, or one OPC can be used to separate the upstream and downstream of the tested filter.
Don't measure. When the second measurement method is used, the OPC should be cleaned before each downstream aerosol concentration detection, so as to
Before starting to measure the downstream concentration, the OPC count concentration has dropped to a level that can reliably determine the downstream aerosol concentration.
c) To ensure that the test results have good repeatability and statistical significance, the total number of downstream particles detected in each efficiency test cycle
Should not be less than 100 capsules.
5.2.4.2.7 Other parameter detection
During the test, the temperature, humidity, static pressure in the air duct where the filter under test is located and the temperature, humidity, and atmospheric pressure of the environment should be measured at the same time.
5.2.5 Filter efficiency calculation
5.2.5.1 According to the OPC measurement results of the number of particles before and after the filter, the filtration efficiency E of the tested filter should be calculated according to formula (1).
E Take the first digit after the last 9 as a significant digit, and the second digit will be rounded off. For example, the measured value E=
99.976%, E=99.98% after revision.
E = 1-
A2-A0
RA1 ×100% (1)
Where.
E ---The filter efficiency of the tested filter;
A2---The concentration of downstream aerosol particles, in units of particles per cubic meter (particles/m3);
A0-the background concentration of downstream aerosol particles, in units of particles per cubic meter (particles/m3);
A1---Upstream aerosol particle concentration, in units of particles per cubic meter (particles/m3);
R ---Correlation coefficient.
5.2.5.2 The lower limit efficiency of the 95% confidence interval, E95%, min should be calculated according to formula (2).
E95%, min = 1-
A2,95%max-A0
RA1,95%min ×100% (2)
Where.
E95%, min --- the lower limit efficiency of the 95% confidence interval;
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