Cleanroom airtightness test specifications

Introduction

This specification aims to ensure the airtightness of Dust-free workshops (areas) and confirm whether there is contaminated air leaking into dust-free workshops (areas) from adjacent dust-free workshops (areas) or non-dust-free workshops (areas) through interfaces such as ceilings, partitions, doors and windows. This test is applicable to dust-free workshops (areas) from level 1 to level 5 to ensure the cleanliness of the production environment and product quality. The test methods mainly include photometer method and particle counter method.

Test methods

1. Particle counter method

When using the particle counter method for testing, the following steps should be followed:

a. Test environment preparation

• Measure the concentration of suspended particles in the external air of the area to be tested, which is required to be at least 10,000 times higher than the concentration in the dust-free workshop (area) and at least reach the particle size standard of 3.5×10^6/m³ to be tested.

• If the concentration of suspended particles in the external air is lower than this value, aerosol should be added to increase its concentration to ensure the effectiveness of the test.

b. Measurement operation

• The particle counter should be kept 5~10cm away from the joint seal or meshing surface to be tested in the clean room (area).

• When measuring, the scanning speed is set to 5cm/s.

• For the test at the open porch, the concentration of suspended particles in the air should be detected within 0.3~3.0m from the open door in the clean room (area).

2. Photometer method

When using the photometer method for testing, the following steps should be followed:

a. Test parameter setting

• Measure the concentration of suspended particles in the external air of the surface to be evaluated, and ensure that it is higher than the 0.1% load value set by the photometer.

• If the reading of the photometer at the 0.1% scale value exceeds 0.01%, it indicates that there is air leakage.

b. Test implementation

During the test, it is necessary to ensure that the calibration and settings of the photometer meet the relevant standards to ensure the accuracy and reliability of the measurement results.

Through the implementation of the above two test methods, the airtightness of the cleanroom (area) can be effectively evaluated, and potential air leakage problems can be discovered and dealt with in a timely manner to ensure that the air cleanliness of the cleanroom (area) meets industry standards. This is crucial to maintaining the safety of the production environment and product quality. 

All test results should be fully recorded and reviewed regularly to maintain effective management and control of the cleanroom (area).