What are your options for using desiccators in a controlled environment like a cleanroom?
In our last article, we discussed the complications that come with using glass desiccators in the cleanroom. They can’t maintain proper levels of humidity, so they must be handled – causing disruption to the process and risking contamination. An alternative to using the glass is to incorporate desiccant-based dry cabinets.
Dry cabinets alternate between two desiccant modules that cycle in and out of the airflow unit. One provides moisture adsorption and the other undergoes regeneration through an integral heating module fan. In this way, the cabinet offers better storage capacity at controlled RH level.
This kind of system is perfect for long-term bulk storage of microelectronic components, moisture-sensitive optical devices, and other similar applications. The cabinets eliminate the need for manually removing and restoring saturated desiccant. The products are easily accessible, thereby not obstructing the process. The even set point control and low relative humidity monitoring offer benefits to this kind of system over the static, or glass jar system. However, the dry cabinet is more complex and expensive to own and operate.
For the most stringent cleanroom environments, the dry cabinet still poses some issues. Fans are used in these systems, which can cause particles to enter the airflow. HEPA filters can be added to capture the contaminants, but they also add an additional moisture load, which can compromise drying efficacy. The fans can also cause turbulence outside of the cabinet, disrupting the essential laminar airflow.
For cleanroom environments that need better contamination control than the two desiccators we’ve described, there is a third option. We will delve into that in our next article. For expert cleanroom certification and validation, contact Gerbig Engineering Company. We’ve been in the industry for thirty years helping companies with compliance as well as cleanroom construction. 888-628-0056; firstname.lastname@example.org