Desiccators in cleanrooms are usually glass jars used to store pre-dried samples of hygroscopic chemical reagent. They’re sometimes also used to cool substances that were heated in a beaker. In a laboratory, they are very useful, but in a cleanroom, they can be a contamination hazard.
One of the primary issues with glass desiccators is that cleanrooms usually require very precise humidity controls. The devices manufactured in semiconductor, medical device, and pharmaceutical cleanrooms are moisture-sensitive devices (MSDs). The desiccators cannot maintain these extremely low levels of relative humidity.
Desiccators create a drying effect through adsorption using a desiccant powder like calcium chloride or silica gel on the bottom. The sample sits on a small platform, and the jar is sealed using silicone grease. Once this system reaches its saturation point, it can’t provide moisture protection. Saturation is visible when the powder changes … Read More »
Years ago, “Millennial” seemed like a dirty word. As they began infiltrating our workforce, generations above them judged harshly, finding them entitled and lacking a work ethic. Now that they are fully immersed in our working culture, we have found that they bring opportunities for growth and evolution. However, the youngest of this generation are getting their first jobs out of college, and their worlds are very different from those of us who have been working for fifteen years or more. The question is how do we train these young people?
It’s important to recognize that Millennials do have different needs when it comes to learning a job. Their reality has always included advanced technology. They have access to an infinite amount of information. They learn and process information differently than generations before, so if you current training strategy has been … Read More »
If you’re looking to avoid evaporation as a drying technique in a cleanroom, you may be interested in the Marangoni System.
When water evaporates, because it is leaving as a gas, it leaves behind water spots. In a controlled environment, this is something to avoid; the water spots are basically made of contaminants. In order to remove water, then, some people consider the fascinating Marangoni System.
James Thomson found that gradients in surface tension arise from concentration differences in solution. After that, Carlo Giuseppe Matteo Marangoni found that liquid will flow along a gas-liquid or a liquid-liquid interface from areas of low surface tension to high. These two combined discoveries led to the Marangoni System.
The Marangoni effect is stimulated by anything that reduces surface tension. A cleanroom dryer would use a DI water bath with a headspace of IPA in nitrogen. IPA … Read More »
Whether you’re renovating or building a cleanroom, there are numerous factors that come into play. Without the right planning and preparation, your cleanroom build can be a headache at best and a disaster at worst. The purpose of your cleanroom and your unique facility are individual to you, so do your homework. Here is a quick list of do’s and do not’s.
You Should Definitely:
Know the purpose and functions of the space. Clearly establish this by using a recognized standard like ISO 14644. You want to set the class of cleanliness and criteria like humidity setpoints and temperature.
Have clearly identified requirements for maintaining your operations during construction.
Create requirements for vibration performance.
Make sure you have adequate space for mechanical systems by checking vertical clearance. Also check the vertical clearance for moving equipment – do you need to use elevators?
Check that there is … Read More »