The purpose of a cleanroom is to control an environment by limiting the presence of sub-micron particles and adjusting insufficient environmental conditions. There are many different levels of controlled cleanroom environments and this is what separates one from the other. That being said, there are many different hidden sources for cleanroom contamination.
Paper, pencils and retractable pens. A major cause of particle contamination is writing utensils and supplies. There are special cleanroom writing materials that are recommended. If there is a chance that non-approved paper or writing utensils have been used, it must be closed.
Processing equipment and tools. It is vital that all equipment that is brought into the cleanroom is examined thoroughly and properly cleaned. There are specialised cleaning methods that are used for difficult access surfaces. It’s important to assess all equipment and develop a plan to minimise the impact it will have on the cleanliness of your environment.
Cleaning products. Regular household or industrial cleaning products are not acceptable for cleanroom maintenance. Non-particulating wipes and mops must be used for all cleanroom-cleaning needs. There are special cleaning products that can be purchased for specific cleanroom use. Cleanroom vacuums must have a classification rating equal to or better than the cleanroom it is used in.
Labels and tape. Many labels are made from paper with adhesives. When using these tapes they tend to leave residue behind. Be sure to purchase your cleanroom tapes from a certified cleanroom consumable supplier.
Inappropriate cleanroom garments, gowning protocol, inadequate gowning for a particular class or infrequent change out intervals of suits, smocks or other garments and floor mats. This is estimated to be 80% of where cleanroom contamination comes from. Most airborne particles migrate out of their cleanroom garments.
Raw material and product. Before any raw materials or products are brought into the cleanroom it must be cleaned properly. The degree of cleaning depends on the class of the cleanroom, the destination of the raw material and the possibility of any cross contamination to other processes.
Cleanroom contamination is no joke and shouldn’t be taken lightly. For those who work in cleanrooms, they understand the importance of keeping any kind of contamination out of the room. There are times when things get contaminated and you need to find the source. There are many different reasons that a cleanroom could be contaminated but hopefully, this list can help you narrow it down and prevent it in the future.