There are several important things to consider when transferring materials into a controlled environment. Consumables and equipment can introduce unwanted contaminants, especially if they are not specifically designed for cleanroom use. In many cases, the items can be wiped down, prepared, and/or repackaged to make them suitable for cleanroom use.
- Cardboard and wood is not allowed because these materials can shed particulate and even introduce mold into the environment. Items such as gloves packaged in cardboard should be removed from the box before they are brought in.
- Some cleanroom guidelines require bags and containers be wiped down with 70% isopropyl alcohol.
- If carts are used, make sure they are properly wiped down and disinfected (including the wheels) before entering clean areas.
When transferring materials into the cleanroom, the main goal is to reduce any possibility of contamination. There are a variety of ways to achieve this. Some of the methods include using multiple bags, disinfecting the materials in several stages, and sterilization once in the cleanroom.
Multiple Cleanroom Bag Method
Using this method, multiple cleanroom bags are used to protect materials as they transition into the clean area. For multiple-level classification areas, a single outer bag is removed at each step. Once the item reaches the final destination, the final bag should be removed. This method reduces the likelihood that contaminants from lower-level classifications areas will be tracked into the processing area.
Cobalt Blue Sterile Wipes are double-bagged and ready for the multiple bag method
The disinfection method entails spraying or wiping materials and/or packaging with a suitable disinfectant before they are transferred to the final processing area. Benefits of this method include greater control of disinfectants used and the amount dispensed. Typically, the materials are wiped using traditional cleanroom wiping techniques – wiping in one direction using parallel, overlapping strokes starting from the cleanest area and wiping towards the least clean area. It should be noted that some cleanroom procedures implement the disinfection method in addition to the multiple bag method.
Related Topic: Disinfecting Wiping Methods
Direct Sterilization Method
Last is the direct sterilization method. This method is the most efficient, but it comes with a price. It requires a unit such as a pass-through autoclave which provides a sterile path in and out of cleanroom environments. Materials are placed into one side of the autoclave and the sterilization cycle begins. Common cycles typically include a combination of vacuum, steam, and cooling – depending on the material placed into the autoclave.