use of the Blue M Stabiltherm model 200A

I am the questioner, but I thougfht of something and I would like to get feedback/opinions. I know that Handbook of Chem physics used to show standard humidity conditions by enclosing particular materials in a jar to get to a specific RH. Any opinion on if I make such a jar, or series of jars and put my pharmaceutical stability samples (in their proper packaging) into the jars, and put them into the oven. That should give me the temperature control and the specified relative humidity. Any comments? Thanks pharmtechdon

We make humidity chambers similar to the Blue-M. How much patience do you have? High humidity (90%+) is relatively easy by adding a heated water pan in the chamber (or external steam generator), with a sensor and heater control. The sealed jar requires you start with a known amount of water, but I'm not familiar with this method, except that it exists. I suspect the amount of water is very small, which is a challenge. Some lab company sells 'bell jar' humidity test systems, you could study them. But 60% is somewhere in the middle, and is best with dehumidification capability. It is a big DIY project, and lots of time tinkering to get control to work properly. And picking humidity sensors is no walk in the park. In either case, you may also be fighting the chamber's main cooling system, which may be pulling moisture out of the air when you don't want it to, depending on how it is designed. So, unless Blue-M has this designed for RH control with an easy add-on package, I would advise against spending your time and money on DIY. Good luck!

Thanks for the response. I don't have that much patience for this particular project. I will pass on your suggestions. Don