It is from USA, international applied, used inChina.
Test dust source is manmade dust included the big grain size, high concentration and road dust. Dust’s main component is the dust which is filtered and in the specified area, it can be mixed the specified amount fine carbon black and short fiber, or only mixed the carbon black. Most of dust for testing which is used in different country was bought the Arizona Road Dust from the desert zone of Arizona inUSA. Chinese standard is specified to use the dust from some village in loess plateau, the test amount is dust weight.
Air filter is installed the standard test wind tunnel, the wind ward send out the dust continuously. At set intervals, it tested the dust weight on the air filter or the dust collection amount of air filter, and get the filter efficiency at this stage. The final weighted efficiency is the weighted average value of the dust amount of sending out at the different stage’s efficiency.
Arrestance’s termination test condition: when the promissory final resistance value or efficiency value dramatic declined. The so-called “promissory” means that the promise between the customer and tester, or the rule of tester himself. Obviously, the termination condition is different; the weighted efficiency value is different.
When the test is stopped, the weight of filter held the dust is called dust holding capacity.
It is fromUSA, international applied except forChina.
Test plat from and the manmade dust and Arrestance is the same. The dust amount is the light amount of the sampling site of high-efficiency filter paper.
After each section of sending out dust test, it measured the light amount of sampling site of high efficiency Filter paper in the normal condition(do not send out dust), it can be calculated the so-called “filter efficiency” as per the specified calculate method by comparing the difference of the light amount of filter paper. The final colorimetric efficiency is the weighted average value of the dust amount of sending out at the different stage’s efficiency.
The condition of termination test is similar to the Arrestance’s condition: when the promissory final resistance value or efficiency value dramatic declined.
Dust-sopt is used in the high efficiency air filter fro general ventilation. Most of air filter used in the air conditioner is this kind of filter.
Dust-sopt is the most universal test method for the general ventilation air filter in the foreign country fro more than 30 years.
But dust sopt method is very complex, so it is being instead of particle counting method.
Strict dust-sopt method is destructive test; it cannot be test method of daily products. But, the factory can measured the initial colorimetric efficiency (the initial colorimetric efficiency is much lower than the average colorimetric efficiency), it can be judged the stability of product performance.
It never used this dust-sopt method inChina, there is no the related test platform.
The related standard：USA ANSI/ASHRAE 52.1-1992，European CEN779，China GB12218-89.
Atmospheric dust amount counting Method
Dust source is the atmospheric dust in the atmosphere. The amount is equal or larger than the all quantity of particle matter in some grain size. The instrument is the optics particle counter or laser particle counter. The efficiency value is new filter’s initial efficiency.
Atmospheric particle counter method is used in the filter for general ventilation. The efficiency value is only on behalf of the new filter’s performance.
Chinese filter efficiency classification is based on the atmospheric particle counter method. it is earlier than European andUSA.
But the atmospheric particle counter method is rough, the related department is thinking about to amend the standard now.
Particle counter method is applied in European, trial implementation in USA.
Test platform is the similar to the Arrestance and dust-sopt, high concentration manmade dust is similar to the Arrestance and dust-sopt. The dust quantity is quantity of the minute grain size of particle matter; the instrument is laser particle matter counter.
After each section of sending out dust test, it is measured the quantity, and calculate the filter’s efficiency for the different grain size PM. When it reached the condition of termination test, calculating the instantaneous efficiency in different stage is as per the weighted average of the amount of sending out dust in different stage.
It is used the manmade dust is generally specified multi disperse phase liquid drop when doing the counting measurement, sometimes, it is also used the same quantity Latex ball as the demarcate counter specified the standard PM.
Counter efficiency is not only a single value, but is a filter curve of following the different grain size. European test indicated the counter efficiency value at the 0.45μm is similar to the efficiency value of colorimetric method.USAstandard used the efficiency of different grain size range separately as different class filter.
Strict counter efficiency is got from destructive test. Manufacturers test the initial counter efficiency to judge the stability of the products performance usually.
The efficiency of counter method is being instead of colorimetric method.