How to perform performance testing on a clean workbench before use?

    Clean workbench is mainly used in microbiological experiments, biological product drug testing, and other operations in places with high requirements for environmental cleanliness and air cleanliness. A clean workbench is a piece of equipment with local purification functions that must undergo rigorous testing before use to ensure compliance with relevant cleanliness and safety standards. The following is a detailed introduction to mid-level purification.

    1. Preparation before testing:

(1) Ensure that the workbench is in good operating condition and has been thoroughly disinfected to ensure the hygiene and safety of the testing environment.

(2) Complying with the regulations, the number of testers shall not exceed two, and the clothes shall be changed by the prescribed procedures.

(3) The purification air conditioning system operates normally for more than 30 minutes to ensure that pollutants in the air can be effectively filtered and removed.

    2. Illumination:

(1) Testing requirements: The indoor temperature has stabilized and the light source output has stabilized before testing.

(2) Testing method: Test according to the illumination detection method specified in the "Standard Operating Procedures for Testing of Monitoring Items in Clean Rooms". Take three points at equal distances at a height of 0.3m from the table for testing, record the data, and calculate the average.

    3. Dust particles:

(1) Detection method: Use a CLJ-D dust particle counter to detect dust particles by the dust particle detection methods specified in the "Standard Operating Procedures for Detection of Monitoring Items in Clean Rooms".

(2) Determine the number of sampling points: 30 minutes after the equipment is turned on, set three test points 20cm away from the edge of the operating table and 10 to 15cm high from the surface, 25±5cm apart from left to right.

(3) Determine the sampling volume: Calculate according to the formula VS=20/Cn.m×1000, where VS represents the sampling volume of each sampling point, and Cn.m represents the concentration of the particle size considered for the air cleanliness level of the tested clean room. limit. For particles with a particle size of 0.5 μm, the sampling volume is 5.7L. For particles with a particle size of 5 μm, the sampling volume should be increased to ensure accuracy. This time, the sampling volume was determined to be 28L.

(4) Determine the number of sampling times: three measurements are required for each sampling point.

    4. Inspection of sedimentation bacteria:

(1) Determination method of sedimentation bacteria: Test according to the detection method of sedimentation bacteria specified in the "Standard Operating Procedures for Testing of Various Monitoring Items in Clean Rooms".

(2) Instruments and equipment used: autoclave, constant temperature incubator, petri dish (φ90mm×15mm borosilicate).

(3) Determine the sampling points and number of Petri dishes

(4) First, strictly sterilize the surface of the test equipment and Petri dishes.

(5) Due to the small area of the workbench, only two sampling points need to be selected, two trisection points distributed on the diagonal.

(6) Because the workbench is level 100, according to the minimum number of Petri dishes required for settling bacteria (φ90mm, settling for 0.5h), the number of Petri dishes at each sampling point should be 7, and a total of 14 Petri dishes need to be prepared.

(7) Take two ф90mm×15mm Petri dishes, inject 15ml of culture medium into each, place them at the measuring points respectively, open the lids and expose them for 30 minutes, cover the Petri dishes, and invert them.

(8) Cultivate in a constant temperature incubator at 30-35°C for 48 hours to count bacterial colonies with the naked eye, and record the number of colonies generated (CFU).

(9) Check with a 5 to 10 times magnifying glass to see if there are any omissions. If there are two or more overlapping colonies on the petri dish, two or more colonies will still be counted when distinguishing. Repeat the above operation 7 times.

    5. Determination of wind speed:

(1) Measurement method: Detect the wind speed according to the method specified in the "Standard Operating Procedures for Testing of Various Monitoring Items in Clean Rooms"

(2) Measuring point location: For rectangular air ducts, divide the measurement section into several small sections of equal size. Each section should be as close to a square as possible, with a side length not exceeding 200mm. Set the measuring point at the center of the small section. However, the number of measuring points in the entire section shall not be less than 9.

(3) Detection method: Use a hot bulb anemometer for measurement, and perform specific operating steps by the standard operating procedures of the hot bulb anemometer.

    6. Wind direction detection:

(1) Measurement method: Detect the wind direction according to the method specified in the "Standard Operating Procedures for Testing of Various Monitoring Items in Clean Rooms"

(1) Qualification standard: The airflow direction in the work area deviates from the specified direction by no more than 14°.

(2) Measuring point location: Measuring point A is located at the center of the longitudinal section of the operating table, and measuring point B is located at the center of a horizontal plane 0.5m away from the operating table.

(3) Detection method: Use the hanging wire method, that is, hang a single wire for observation, and compare it with the pre-drawn 14° angle, which must not be larger than the 14° angle.

    7. Noise detection:

(1) Arrangement of detection points: Since the area of the clean room is small, only one point needs to be selected for detection in the center of the workbench. A total of three measurements are taken and the average value is calculated.

(2) Testing method: Use a noise meter for measurement. The specific operating steps are carried out by the standard operating procedures of the noise meter.

    In addition to the tests mentioned above, the clean workbench also needs to be tested in many aspects such as protection and electrical safety. When using a clean workbench, you must strictly follow the prescribed usage methods and precautions, and perform routine maintenance to ensure that the clean workbench is always in good operating condition.