Detection is an important project after the construction of purification project. In the process of testing various indicators of purification project, some of the cleanliness tests are not qualified, some of them are part of the factory building, and some of the whole project. If the test is not qualified, although both parties through rectification, debugging, clearance and so on. Hard work to meet the requirements of the project, but it wastes a lot of manpower and material resources. Not only has it delayed the construction period of the whole project, but most importantly, it has delayed the process of GMP certification, which is not worth the money. In fact, some reasons and defects can be completely avoided before testing. According to Edward's years of experience in purification, the main reasons for the unqualified cleanliness of purification engineering are as follows:
1. The design of purification workshop is unreasonable.
This phenomenon is relatively rare, mainly in the construction of some small clean rooms with low purification level requirements. Nowadays, the competition for purification is fierce. In order to get the project, some construction units have offered lower quotations in the bidding. In the later stage of the construction of the purification project, some units do not understand the practical situation, cut corners and use air-conditioning and ventilation compressor units with lower power, so that the supply air power does not match the purification area, resulting in unqualified cleanliness.
2. Replace high-end products with low-end products
In the application of clean room high-efficiency filters, the state stipulates that three-stage filtration of primary, intermediate and high-efficiency filters should be adopted for air purification treatment with cleanliness of 100,000 or more. In the verification process, the author found that a large-scale purification project used sub-high efficiency air filter instead of high efficiency air filter at the purification level of l0000, which resulted in unqualified cleanliness. Finally, the high efficiency filter was replaced to meet the requirements of GMP certification.
3. Poor design and commissioning of return air duct or return air outlet
In terms of design, sometimes due to space constraints, it is not possible to use "top-feeding side return" or insufficient number of return air outlets. After removing the design reasons, the adjustment of return air outlet is also an important part of engineering. If the debugging is not good, the resistance of the return air outlet is too large, and the return air volume is less than the supply air volume, the cleanliness will also be unqualified. In addition, in the construction, the height of the return air outlet from the ground also has an impact on the cleanliness.
4. Clean air conditioning system is not cleaned up
During the construction of the purification project, the whole purification air conditioning system, especially the air supply and return pipes, is not completed at one time. The construction personnel and the working environment will cause the pollution of ventilation pipes and filters. If it is not clean, it will directly affect the test results of the purification project. The improvement measures are to clean the pipeline while it is being constructed. After the pipeline is completely cleaned before it, it can be sealed with plastic film to avoid environmental pollution.
5. Clean workshop is not thoroughly cleaned
There is no doubt that the purification workshop must be thoroughly cleaned before testing in order to carry out testing. The final cleaning personnel are required to wear clean work clothes for cleaning in order to eliminate the human pollution caused by cleaning personnel. Water, pure water, organic solvents and neutral detergents can be used as cleaning agents.