Items supplied outside the clean room and their packaging
If the supplier of the item knows little about the clean room requirements, or does not care at all, then the item it supplies may have been severely contaminated when it enters the clean room. In some cases, this may be an important cause of pollution. Therefore, some measures should be taken to solve such problems.
1. External supplies should be produced in a clean environment
The items supplied to the clean room must be produced in a clean environment, and the cleanliness standard should be the same as the clean room supplied by the product. If the externally supplied items cannot reach an appropriate level of cleanliness when they are delivered, they must be cleaned in a clean room, but this may be less effective. More and more companies are manufacturing and supplying parts and components required for clean room production in a clean environment. Clean room managers should emphasize to the company's purchasing department that they must pay attention to the production environment of clean room suppliers. We should try our best to choose clean room supplies that are of high quality and low price and are produced in a corresponding clean environment to ensure the cleanliness of the company's clean room and reduce the cost of cleaning external supplies.
It is necessary to visit and inspect the production facilities of suppliers and inspect their production environment. Manufacturers of external supplies may not be familiar with clean room technology. Therefore, some simple suggestions and improvements to their production process may produce good results. Even if the manufacturer does not have a clean production environment, as long as there is a higher level of clean management conditions, the use of gloves, rags, and lint-free clothing for clean rooms can greatly improve the quality of the products.
2. The packaging materials of external supplies should pay attention to the storage and packaging of the product. If the processed product is packaged in a suitable clean packaging method immediately after being removed from the production equipment, the impact of the poor surrounding production environment on the product can be minimized. The packaging methods and packaging materials for external supplies must consider the cleanliness level of the clean room supplied. The dimensions and appearance of the packaging should meet the requirements for pollution prevention during storage, transportation, and unpacking. The main requirements for packaging materials are: The following points. 1) Non-polluting of packaging materials: the packaging materials themselves are required to not produce particles, fibers, polluting gases and steam, etc., not to be obviously charged with static electricity, and not to chemically react with the packaging; 2) The packaging materials must be clean Materials that meet the required cleanliness of the packaging items; 3) Strength and durability of the materials: The packaging materials should withstand the effects of temperature and humidity, external forces, and ultraviolet rays, so as to ensure the required tightness and avoid damage during transportation and storage. The pollution brings the pollution into the clean room.
Good packaging for supplies outside the dust-free environment can not only avoid product damage during transportation, but also minimize product contamination from the external environment. Commonly used plastic materials are plastic films or prefabricated packaging plastics. Compared with many other materials, plastic materials have less particle, fiber, and chemical pollution. The size of plastic pollution depends on the type of plastic used, manufacturing method and packaging method. Therefore, the suitability of the plastic packaging used should also be tested. Some plastics generate static electricity, which may damage the product. If anti-static plastic is used, it has less adsorption effect on particles and fibers, so it is also cleaner. If molecular pollution needs to be controlled, some plastic packaging materials (such as PVC packaging materials) may not be applicable.
3. The packaging method of externally supplied items should also consider the need for several layers of packaging. If the articles used in the clean room are multi-layered packaging, they can be opened one layer at a time and gradually disassembled during the transportation to the clean room, which can ensure that the articles are clean when they are delivered to the clean room. Vacuuming the outer packaging with a vacuum cleaner and wiping with a damp cloth helps to keep it clean, especially at the beginning of shipping the product to the clean room. As the product gradually enters the clean room, the outer packaging becomes cleaner and cleaner. Relatively speaking, the cleaning of the outer packaging becomes less necessary.
There are various correct ways to pack items. Different items, different uses, different designs of material transfer airlocks, etc. make the packaging methods very different. Therefore, the management personnel of the clean room must specify the applicable packaging materials, and stipulate the procedures for cleaning the packaging and opening each layer of the package when the required items enter the clean room.