First, the instrument used: dust particle counter

Second, the principle of leak detection: This experiment applies the principle of light scattering, the counter uses the principle of photomultiplier tube to accept the light reflected by the dust particles to determine its size and quantity, and scientific analysis.

Third, the requirements of the experiment

1. Status: It needs to be tested in a static environment, and the relevant personnel cannot exceed 2 people;

2, pressure difference: for different cleanliness, the static pressure difference is generally 5Pa, the static pressure difference between the clean area and the non-clean area is 10Pa;

3. Environment: The surrounding temperature should be controlled between 18--26 °C, and the relative humidity should be controlled between 45--65%.

     Fourth, the experimental method:

1. The instrument counter is wiped with water and 75% alcohol and then irradiated with ultraviolet light for about 30 minutes, and then passed into the clean area;

2. The counter is placed horizontally on the table, and the plastic tube port for measurement is connected to the nozzle of the filtering device;

3. When the power is turned on, the device will automatically start detecting;

4. Observe the displayed data;

5. Turn off the power in time after the test is completed.

V. Conclusion of the experiment:

Through the above experiments, we can see which primary filter has leakage, need to be plugged or replaced, and must be re-tested after repair or replacement of these equipment. Under normal use, it is generally necessary to perform at least one test every year to see if the performance of the device has changed.