Suzhou Yikang Environmental Testing Co., Ltd

Electronic Industry Cleanroom Testing Scheme

Cleanroom testing items: air exchange rate (wind speed), pressure difference, temperature, humidity, noise, illumination, cleanliness (dust particles)

Client Unit:***Electronics Company

List of Testing Instruments

1The air volume or wind speed test shall comply with the following regulations:

1 For a unidirectional flow clean room, the method of determining the air supply volume should be based on the average wind speed of the cross-section and the product of the cross-section, and the high-efficiency filter should be taken away300mmThe section perpendicular to the airflow is used as the test plane. The test plane should be divided into equal grids, each grid size should be600mm×600mmThe size of the end air filter should be measured at the center of the grid or not less than 3 Point. The testing time for each point should not be less than10sThe average, maximum, and minimum values should be recorded, and the arithmetic mean should be used as the average wind speed.

2 For non unidirectional flow cleanrooms, the testing time for each point should not be less than10s.

3 At each end of the air filter hood method, the supply air velocity is measured to determine the supply air volume. The number of measuring points at each testing location should not be less than 3 Point.

2 The static pressure difference test shall comply with the following regulations:

1 The determination of static pressure difference should be carried out when all doors are closed.

2 Various types of micro pressure gauges should be used for the instrument, and the sensitivity of the instrument should be less than1.0Pa.

3 When there are multiple clean rooms (zones) in a cleanroom, the pressure difference test between the innermost room and adjacent rooms should be started, and the test should be carried out in order outward.

4Take one point from each room for testing

3. The cleanliness testing should comply with the following regulations:

1 The sampling amount should be greater than1l/minOptical particle counters should be selected based on requirements such as particle size discrimination ability, applicable range of particle concentration, and counting efficiency. The instrument should have a valid calibration certificate.

2 The minimum number of sampling points should be calculated according to the following formula:

NL=√Ain the formula ——Minimum sampling points;

( A ) ——The area of a clean room or controlled clean area（m²）.

The sampling points should be evenly distributed throughout the entire area of the clean room (zone) and should be located at the height of the work area.

3 The sampling amount for each sampling point should be determined according to the following formula:

VS=[20/Cn,m]yes100

in the formula Vs ——The amount of each sample taken at each sampling point, inLIndicating that whenVsWhen large, sequential sampling method can be used. The minimum sampling time for each sampling point is1minThe sampling amount should be at least2l；

Cn,m——The limit value of the measured particle size for the cleanliness level of the clean room air being tested（p/m³）；

20 ——The number of particles that can be measured when setting the air cleanliness level limit for the measured particle size.

Calculation results of sampling volume for individual sampling points in clean rooms at all levels

1. Class 100 cleanroom (such as 1 Workshop2/3Laboratory)

˜≥0.5μmParticle sampling quantity：

· VS=[20/Cn,m]yes100=[20/3520] yes100=0.568L

· Due to the calculation results（0.568L）＜2L, must be taken according to mandatory requirements2L.

˜≥5μmParticle sampling quantity：

· VS=[20/Cn,m]yes100=[20/29] yes100=68.97L

• Actual execution standardsA single sampling point in a Class 100 cleanroom needs to be sampled according to≥68.97LSampling (considering both particle sizes), using100L/minCounter, sampling time1minute

2. Class 1000 cleanroom (such as 5 Workshop)

˜≥0.5μmParticle sampling quantity：

· VS=[20/Cn,m]yes100=[20/35200] yes100=0.0568L

· Due to the calculation results（0.0568L）＜2L, must be taken according to mandatory requirements2L.

˜≥5μmParticle sampling quantity：

· VS=[20/Cn,m]yes100=[20/293] yes100=6.83L

• Actual execution standardsA single sampling point in a Class 100 cleanroom needs to be sampled according to≥68.97LSampling (considering both particle sizes), using100L/minCounter, sampling time1minute

3.Class 10000 cleanroom

˜≥0.5μmParticle sampling quantity：

· VS=[20/Cn,m]yes100=[20/352000] yes100=0.00568L

· Due to the calculation results（0.00568L）＜2L, must be taken according to mandatory requirements2L.

˜≥5μmParticle sampling quantity：

· VS=[20/Cn,m]yes100=[20/2930] yes100=0.683L

• Actual execution standardsEach sampling point in a 10000 level clean room shall be uniformly sampled according to≥2LSampling, when using any flow counter, sampling time≥1min(such as100L/minCounter sampling test1Minutes)

4Sampling frequency

The sampling points shall not be less than2One, with a total sampling frequency of no less than5time

4The detection of temperature and relative humidity should comply with the following regulations:

1 The detection of temperature and relative humidity should be conducted in a clean room (area) with uniform airflow distribution, and should be arranged after the trial operation of the purification air conditioning system is qualified. The temperature and humidity detection should be carried out after the purification air conditioning system has been running and should be stable at least.

2 The relative humidity detection should divide the clean working area into equal area grids, and the maximum area of each grid should be100m²Each grid should have one measuring point, but each room should not have less than 2 A measuring point.

3 The detection detector should be installed at a working height within the clean room (area), and should be no less than the ceiling, walls, and floor of the clean room (area)300mmAnd the impact of possible heat sources in the clean room (area) should be considered.

4 The testing time should be at least1.0hAnd should at least6minconduct 1 Next time（30s）Reading and recording.

5.Illumination testing shall comply with the following regulations:

1 Portable automatic recording illuminance meters should be used for illuminance detection in clean rooms (areas).

2 Illumination detection should be carried out after the indoor temperature is stable and the light output of the light source is stable. The illumination detection of clean rooms (areas) should not include local lighting and backup lighting for production equipment, etc.

3 The illuminance detection point should be located at a working height, preferably above the ground0.85mShould be every25m²Set up a measuring point.

6Noise detection

E.6.1In general, only detection is allowedASound level noise, if necessary, a sound level meter with an octave band analyzer can be used, according to the center frequency 63、125、250、500、1000、2000、4000The8000HzOctave band detection, near the measuring point1mThere should be no reflectors inside. The minimum scale of the sound level meter should not be lower than0.2dB（A）.

E.6.2The height of the measuring point from the ground1.1mThe area is15m²The following clean rooms can only measure the center of the room 1 Point,15m²The above clean rooms except for the center 1 Outside the point, the diagonal should be measured again 4 Point, each from the side wall1mThe measuring points are oriented towards each corner.

E.6.3When it is a mixed flow clean room, the noise in the unidirectional flow area and non unidirectional flow area should be measured separately.

E.6.4When conditions permit, it is advisable to measure the background noise of the air conditioning purification system after it stops running, and the difference between indoor noise and background noise should be less than10dB（A）Correction should be made to the measured point values: difference（6～9）dB（A）Time reduction1dB（A）, difference（4～5）dB（A）Time reduction2dB（A）, difference3dB（A）Time reduction3dBThe difference is less than3dB（A）The measured value is invalid.

7Judgment criteria