Hepa Filter Integrity Test

Usually, engineers in electronic component preparation factories or circuit board development will perform aging operations before the official use of electrochemical gas sensors.








So for us amateurs, we must be full of questions, what is electrochemical gas sensor aging? What is the purpose of aging?

I. What is aging test?

Commonly understood is the electrochemical gas sensor from the production to the factory to make factory inspection between the process of electricity called aging, in order to make the catalyst surface impurities reaction off, so that the zero point current down.

When not in use, there will be some other gases adsorbed on it, through aging can be reacted off, and work more stable.


When aging, the working electrode is controlled within the required bias pressure range relative to the reference electrode, so that the sensor can enter the ready working state.






2.Purpose of aging?

In the manufacturing process of the sensor, in order to better ensure the quality of the sensor products, after the completion of the production will simulate the actual use of the product environment to make it energized to test the performance and stability of the product.

For the aging of the sensor, it is not only necessary to provide the corresponding working environment, but also to record the current situation every once in a while, and constantly provide the trigger signal to make its action and monitor whether its output signal is normal.



The current popular sensor aging technology and method in China is to connect the sensor to power and load, and keep the sensor connected to power for a period of time, which can range from a few hours to a few days.

If the sensor does not fail during this period of time, the sensor passes the aging test.


Therefore, the sensor needs to go through a period of aging test before leaving the factory, so that some quality problems of the sensor can be exposed in the aging test.








For more gas industry news and science, please pay attention to Facebook "Beijing Zetron Technology Co., Ltd"  , if you want to buy gas sensors / gas analysis equipment, or consulting gas solutions, please contact us: 400 015 1600/156 9978 5629

With the development of China's environmental protection activities, China's environmental monitoring technology has also made great progress. The production of environmental monitoring instruments has reached a certain scale. At the same time, with the diversification of flammable gas detectors, other gas detection devices have also appeared on the market.



For example, the four-in-one gas detector guarantees people's work and life to a certain extent.



Four-in-one gas detector uses a special circuit to measure the detector current. After the combustible gas enters the circuit chamber, half of the gas is ignited enough to contain the combustion catalyst.



When the gas burns, the heat and power circuit passing through the current test area change. This change will activate the warning device.




Infrared combustible gas detector works completely differently. The gas entering the test chamber will generate radiation. In fact, upon reaching the gas, half of the gas entering the receiver returns to the transmitter.







The detector measures the intensity of the two beams to determine whether there is combustible gas. If they are the same, everything is fine, but changes in the beam intensity on the air side can cause problems.



Risk of toxic gas leakage in many industrial processing plants, such as chemical products, oil/gas, electricity, food and beverages, pharmaceuticals, pulp/paper and sewage treatment, usually including pipes, valves, tanks, burners, refrigerators, shunts, lighting systems , Aeration boxes and other equipment.



When the four-in-one gas detection instrument detects toxic gas, the gas detector should first pay attention to the inherent problem: adjust the concentration and other characteristics to a high concentration according to the chemical stability of the toxic gas.



The response time of the sample is usually very slow due to the inactive active traction force that depends on the airflow. The calibration of 4-gas detectors is usually very difficult, requiring the conversion of special parts and the expansion of operating modes, as well as flow calibration.



The meaning of flow diffusion implied by monitoring and calibration is not always a good record.



Then, if adjustment is required through the control panel, the calibration may become complicated, and the detection head of the remote diffusion gas detector may be affected by the gas. Some applications may generate interfering gases.



Sample extraction method can place the sensor upstream of the sensor by a chemical cleaning machine to absorb noise. After the surrounding pressure sensors are diffused, all gas sensors will measure the partial pressure, actively extract the sensor samples, and work at a slightly higher pressure.



Therefore, the output sensitivity of the sample stretcher is usually higher than the output sensitivity of the diffusion sensor. In gases with low toxicity, this may be an important regulatory level. But it has the characteristics of how much toxic gas is needed.

As the epidemic continues to develop, masks have become a necessity for our travels, and are indispensable to ward off bacterial viruses and microscopic particles from passing through the respiratory tract to the human body. Wearing a mask is to block airborne droplets with germs, and the requirements for material and filtration efficiency are particularly important.







With the spread of foreign epidemics, the problem of insufficient supplies for epidemic prevention in various countries is very prominent. As a major manufacturing country, China has become the first choice for countries to purchase epidemic prevention materials. The "mask filtration efficiency tester", which is the most in demand nowadays, is used to test the protection effect and filtration efficiency of daily protective masks and respirators against particulate matter, and is also called particulate matter protection effect and filtration efficiency tester, particulate matter filtration efficiency tester, etc.







Here, We uses professional equipment to show you how to test the high efficiency filtration of particulate matter.








Aerosol photometer





Aerosol photometer is a front scattering linear photometer. It is composed of vacuum pump, light scattering chamber, photomultiplier tube, signal processing converter and microprocessor. Its working principle is: the airflow is extracted to the light scattering chamber by the vacuum pump, and the particulate matter inside will scatter the light to the photomultiplier tube, in which the light is converted into an electrical signal, and then after a series of digital analysis and processing, it will become the reading on the screen.



PM-350 aerosol photometer for pharmaceutical and food production enterprises is used for on-site leak detection after the installation of high efficiency filters and their systems, mainly to check small pinholes and other damages in the filter material, such as frame seals, gasket seals and leaky seams on the filter frame. The purpose of leak detection is to detect the defects in the high efficiency filter itself and installation in time by checking the sealing of the high efficiency filter and its connection parts with the installation frame, etc., and take corresponding remedial measures to ensure the cleanliness of the area.







PM-350 aerosol photometer can automatically switch upstream and downstream aerosol concentrations to determine whether the filter has leaks. The portable scanning probe enables the operator to quickly and accurately identify leak points in remote locations and determine other leak ratios, and the display panel will show an alarm when the alarm boundary is exceeded.





Aerosol generator

The aerosol photometer is used in conjunction with an aerosol generator for leak detection of high efficiency filters. In fact, in many practical tests, an aerosol generator is required to continuously and steadily produce aerosol particles of adjustable concentration with a fixed particle size distribution. Aerosols are mainly designed with special nozzles. Compressed air is blown through a circular slot into the atomized liquid. The shearing force between the nozzle and the liquid is fully dispersed in the so-called annular gap, forming tiny aerosol particles with a large inertial collider volume. When the aerosol particles return to the liquid container, the output particle size is mainly distributed between 0.1 and 10 microns. It is suitable for leak detection of clean rooms and high efficiency filters in medical device inspection institutions, disease prevention and control centers, hospitals, pharmaceutical companies, and high efficiency over device manufacturers.







The AG-1800 aerosol generator can produce aerosol particles with a wide range of diameter distributions, providing enough particles to measure high efficiency filter systems when used with a photometer (flow rate range from 1.500-65,000 cubic feet per minute). Easy to operate, stable performance, suitable for certification, HEPA performance testing and installation.

About high efficiency filter leak detection: For food and drug manufacturers, high efficiency filter leak detection refers to the on-site leak detection after the installation of high efficiency filter and its system, mainly to check the small pinholes and other damages in the filter material, such as frame seal, gasket seal and leaky seams on the filter frame. The purpose of leak detection is to check the sealing of the high efficiency filter and its connection parts with the installation frame, find the defects in the high efficiency filter itself and in the installation in time, and take corresponding remedial measures to ensure the cleanliness of the area. Whether there is leakage. The purpose of dust generation is that the dust concentration upstream of the high efficiency filter is low, so if a particle counter is used to detect the leak without dust generation, it is difficult to detect the leak, and additional dust generation is needed to obviously and easily detect the leak.











Standards






FED-STD-209E, Par. 50 Federal Standard (Cleanroom and Workstation Requirements)



AACC, CS- 1T American Association for Contamination Control (Standard for High Efficiency Filters)



AACC, CS-2T American Society for Contamination Control (Laminar Flow Clean Air Installation)



AACC, CS-6T American Society for Contamination Control (Clean Room Testing and Certification)



IES, RP-CC-001-3 Institute of Environmental Science (High Efficiency Filters)



IES, RP-CC-002-86 Association for Environmental Science (Recommended Approach for Laminar Flow Clean Air Installations)



IES, RP-CC-001-2 Environmental Science Society (Test Clean Room)



NSF, STD No.49- 1992 National Sanitation Foundation (Secondary Laminar Flow Biological Safety Cabinet)



ANSI, N101.1-1972 American National Standards Institute (Efficiency testing of air cleaning systems with filters)



ANSI/ASME, N5101.198 American National Standards Institute/American Society of Mechanical Engineers (Testing of Nuclear Air Cleaning Systems) NEBB National Environmental Balance Agency (Standard for Clean Room Certification Test Procedures)













Product Information 



1.Aerosol photometer PM-350














【Feature】



* The host adopts 5-inch color touch screen, easy to operate and faster data processing



* Intuitive display of leakage rate and pump sampling speed and other data



* Portable scanning probe, 3.5-inch color display, one-touch operation, synchronous display with the host interface, convenient for users to observe the test results



* Automatic switching upstream and downstream



* To ensure reliable and stable data, imported air pump and light source are used



 



【Parameter】







Data display range 





0.0001%-100.0% Multi-color LCD display







Dynamic range





0mg/m3～120mg/m3







Accuracy





1%（ 0.01% to 100%）







Flow control





1cfm（28.3L/min）±10%







Alarm 





When the preset limit value is exceeded, 2 modes of audible and visual alarm can be selected







Aerosol type





 PAO, DOP, DEHS and other multi-dispersion







Standards





NSF49、IEST、ISO14644、EN61010-1：2010、EN61326-1:2006







Power





AC 220V  50/60Hz







Dimension





258cm（L）x178cm（W）x360cm（H）







Weight





9.8kg














2. Aerosol generator HRF-4B (cold)



 



【Features】

* Laskin Nozzle dust production method



* Adjustable manually



* Large capacity loading dust production



【Parameter】








Airborne suspended particle output 





range 50 - 8,100 cubic feet per minute (1.4 - 229 m3min)







Suspended Particle Concentration 





100 µg/L at 810 cfm flow rate







Suspended Particle Concentration 





10 µg/L at 8100 cfm flow rate







Generation type





1 to 7 Laskin nozzles







Compressed air





3 to 18 cubic feet per minute at 20 psi flow







Particle generation





PAO、DOP、polydispersed







Type





 Multiple particle diameters (cold)







Dimensions





25cm（L）X 28cm（W）X23cm（H）












3. Aerosol generator HRF-5C (Hot)





 



【Feature】

HRF-5C is a more user-friendly enhanced aerosol generator, its oil circuit insurance supply system and thermal cut function in the current market belongs to the higher grade of the security system, suitable for certification, HEPA performance test and installation. Need to use inert gas, suitable for AC220v±10%50HZ power supply.



 



【Parameter】








Usable flow rate range 





1,500-65,000cfm(42-1,839.5m3/min)







Occurrence concentration





10ug/L：flow rate65,000cfm( at approx 1839.5m3/min)







100ug/L：flow rate 6,500cfm(at approx183.95m3/min)







Particle generation





PAO、DOP、polydispersed







Generation method 





Heating generation







Compressed gas (inert) 





Nitrogen,Argon,Carbon Dioxide或Helium (50psi))







Power supply





AC220～240VAC,50/60HZ







Dimension





280×390×300mm







Weight





14kg








When applying a pressure of 20psi (0.14Mpa) Note: DOP is not recommended



 



4.Aerosol generator performance comparison table









Model





HRF-4B





HRF-5C







Picture











 













 








Principle





Cold generation





Hot generation







Gas source 





Compressed air 





Inert gas







Gas source pressure 





0.4-0.8mpa





50psi







Dust





PAO





PAO







Power





No





AC220～240VAC,50/60HZ








Note: Heating occurs when oily particles are heated and evaporated and then blown into the system air inlet by inert gas, suitable for the end of the whole air conditioning system for high efficiency filter detection, the advantage is that the whole system only needs a place to produce dust , after the filter upstream concentration is stable, you can test the filters one by one, reducing the time of frequent change of dust production points and debugging dust concentration, also saves the PAO oil for debugging. The disadvantage is that there should be a long section of mixed cold generation ten times the diameter of the air duct, which is not suitable for local FFU units without air supply duct at the top, and not suitable for single biosafety cabinets and clean benches.



Cold generation is made of compressed air and pressurized PAO oil, which is sprayed by Laskin nozzles, and the working number of nozzles is used to adjust the size of dust concentration, which is suitable for local FFU units and clean benches of biosafety cabinets without air supply ducts. There is no thermal occurrence of the convenience, there are also air conditioning systems because of the inconvenience of segmentation detection, and can not use this type of dust generation small amount of dust generation instrument.

For food and drug manufacturers, leak detection refers to the on-site leak detection of high efficiency filters and their systems after installation, mainly to check small pinholes and other damages in the filter material, such as frame seals, gasket seals and leaky seams on the filter frame. The purpose of leak detection is to check the tightness of the HEPA filter and its connection with the installation frame, to detect any defects in the HEPA filter itself and in the installation, and to take corresponding remedial measures to ensure the cleanliness of the area. Whether there is a leak. The purpose of dust generation is to detect leaks without dust generation, as the concentration of dust particles upstream of the HEPA filter is low and it is difficult to detect leaks with a particle counter.





What are the standards for leak detection of HEPA filters?

 

FED-STD-209E, Par.50 Federal Standard (Cleanroom and Workstation Requirements)

AACC, CS-1T American Association for Contamination Control (Standard for High Efficiency Filters)

AACC, CS-2T American Society for Contaminant Control (Laminar Flow Clean Air Units)

AACC, CS-6T American Society for Contamination Control (Clean Room Testing and Certification)

IES , RP-CC-001-3 Institute of Environmental Science (High Efficiency Filters)

IES , RP-CC-002-86 Association for Environmental Science (Recommended Practices for Laminar Flow Clean Air Installations)

IES , RP-CC-001-2 Environmental Science Association (Test Clean Rooms)

NSF, STD No. 49- 1992 National Sanitation Foundation (Secondary Laminar Flow Biological Safety Cabinets)

ANSI, N101. 1-1972 American National Standards Institute (Efficiency Testing of Air Cleaning Systems with Filters)


ANSI/ASME, N5101. 198 American National Standards Institute/American Society of Mechanical Engineers (Testing of Nuclear Air Cleaning Systems) NEBB National Environmental Balance Agency (Standard for Clean Room Certification Test Procedures)








I. Aerosol photometer PM-350



1. 5-inch colour touch screen in the main unit, easy to operate and faster data processing

2. Portable scanning probe, 3.5 inch colour display, one key operation, synchronous display with the host interface, convenient for users to observe the test results

3 Automatic upstream and downstream switching

4. To ensure reliable and stable data, imported air pump and light source are used










Data display range


0.0001%-100.0% Multi-colour LCD display




Dynamic range


0mg/ m3 to 120mg/m3




Accuracy



1% of reading (0.01% to 100%)






Repeatability


0.5% of reading (0.01% - to 100%)




Flow control


1cfm (28.3L/min) ±10%




Automatic zeroing


Automatic zero value establishment




Alarm


2 modes of audible and visual alarm when preset limit values are exceeded




Report


Continuous mode, storage mode (up to 6000 data sets), print mode




Aerosol types


PAO, DOP, DEHS, etc. multi-dispersion




Standards met


NSF49, IEST, ISO14644.






EN61010-1:2010, EN61326-1:2006




Power source


AC 220V 50/60Hz




Dimensions


258 (L) x 178 (W) x 360 (D)




Weight


9.8kg (body), 10.3kg (body, scanning probe)









II. Aerosol Generator HRF-5C

The HRF-5C is an enhanced aerosol generator offering greater convenience to the user, with an oil circuit insurance supply system and thermal cut-out function that is in a higher class of safety systems on the market today, suitable for certification, HEPA performance testing and installation. Inert gas required, suitable for AC220v±10%50HZ power supply.











Available flow ranges


1,500-65,000cfm (42-1,839.5m3/min)




Occurrence concentration


10ug/L: flow rate 65,000cfm (at approx. 1839.5m3/min)






100ug/L: flow rate 6,500cfm (at approx. 183.95m3/min)




Particle generation


PAO, DOP, polydispersed




Generation method


Heat generation




Compressed gas (inert)


Nitrogen, Argon, Carbon Dioxide or Helium (50psi))




Power supply


AC220-240VAC,50/60HZ




External dimensions


Approx. 280 x 390 x 300mm




Weight


Approx. 14kg






III. HRF-4B aerosol generator 


HRF-4B aerosol generator by Laskin Nozzle dust production method, manually adjustable and has a large capacity loading dust production.













Output range


50 - 8,100 cubic feet per minute






(1.4 - 229m3min)




Suspended Particle Concentration


100 µg/l at 810 cubic feet per minute flow rate




Suspended Particle Concentration


10 ug/l at 8100 cfm




Type of generation


1 to 7 Laskin nozzles




Compressed air


3 to 18 cubic feet per minute at 20 psi




Particle generation


PAO, DOP, polydispersed




Gas types


Multiple particle diameters (cold)




Dimensions


(25cm L X 28cm W X 23cm H)




Weight


 7.4KG




Power supply


 Not required