Objective: to detect the quality of high efficiency filter accurately, so as to avoid the leakage of high efficiency filter and affect the production. Methods: the high efficiency filter was detected by dust particle counting. Results: if the suspended particles at each point exceed the required range of clean area, leakage will occur, and it is necessary to plug or replace the leakage.

Conclusion: the method is simple and accurate.

Keywords clean area; suspended particles; high efficiency filter noise

Classification no. of Zhonghuan: r914.2 document identification code: a Article No.: 1006-288202-111-02 In the clean room, high efficiency filter is the key equipment to realize high cleanliness air purification. Therefore, after the installation or replacement of high efficiency filter, the installation and connection of filter must be checked to ensure that the cleanliness of the clean room meets the requirements. The maximum allowable number of suspended particles in the 100 degree cleanliness state is ≥ 0.5 μ m3500.

1 instrument Dust particle counter Wujiang Weifeng purification equipment Co., Ltd. clj-e laser light source

2 experimental principle The light reflected by dust particles is measured by photomultiplier tube in counting and measuring by light scattering principle. The accumulated and digital display are analyzed. 3. Experimental methods

3.1 environmental conditions: temperature control is 18-26 ℃; relative humidity is controlled at 45-65%

3.2 test status: static test, indoor test personnel shall not be more than 2.

3.3 pressure difference: for different cleanliness rooms in the room, the static pressure difference is ≥ 5pa, the static pressure difference between clean area and non clean area is ≥ 10Pa; the room with large dust content in the process shall be kept with relative negative pressure.

3.4 test method

3.4.1 dust particle counter shall be wiped with water for injection and 75% alcohol for disinfection, and then transmitted to the clean area after ultraviolet irradiation for 30 minutes.

3.4.2 place the dust particle counter horizontally on the table. The measuring plastic pipe port is connected to the connector of the filter.

3.4.3 turn on the power supply. After the instrument has self inspection and options, pull the measuring plastic pipe off the rear panel. Port is placed where measurement is required

3.4.4 when testing, the sampling head is 2-4cm away from the high-efficiency filter, and it is scanned slowly along the inner border and middle of the high-efficiency filter. At least 5 points are tested for each high-efficiency filter, and the displayed data is observed. After the test, connect the sampling plastic pipe port to the rear panel of dust particle counter for self inspection. Then turn off the power.

The results of high efficiency filter in 100 clean area measured by dust particle counter??????????????? 4 Conclusion The above measurement shows that the high efficiency filter has leakage. Leakage plugging or replacement is required, and the filter must be retested after repair or replacement. Under normal conditions, the high efficiency filter leakage detection test shall be conducted at least once a year to see if there is any change. It is an important part of cleanliness test. ? references [1] GMP revised 1998 [s] [2] I n 7-5025-4171-3 guidelines for drug production and validation (m) chemical industry press 2003