Safety Precautions
Read Up
Before building a supercritical dryer you should familiarize yourself with how the process of supercritical drying works (duh). You can read all about it on How is Aerogel Made? and Supercritical Drying under the Learn category.
Safety First
Now that you’ve read up on supercritical drying, you know that to do supercritical drying with CO2 requires pressures of >1071 psi and temperatures >87.7°F. In fact, in the process we’ll teach you on Aerogel.org, you will go as high as pressures of 1500 psi and temperatures of 140°F in your manuclave. Even though CO2 is non-flammable, a manuclaveful of gas at those pressures and temperatures stores a lot of energy! If you were to discharge all that pressure at once you could seriously hurt yourself and your manuclave could easily rocket itself and/or debris across a room with dangerous force.
So to be safe, make sure you:
- Work in a well-ventilated, well-lit workspace
- Wear safety glasses at all times
- Don’t wear open-toed shoes or sandals
- Read and follow the directions here carefully
- Don’t substitute unrated or lower-rated parts for properly-rated parts (i.e., pipe fittings rate for lower pressures or temperatures than recommended)
- Don’t cut corners
- Don’t rush or jury-rig something to get it done faster or cheaper
- Don’t leave something out thinking you can get away with it
- Stop and ask for help if you get to a point where you’re uncertain about something
- Have someone check in on you while you’re working
And, furthermore:
- Always, always, always include both a thermometer and pressure gauge on any pressure vessel you build, especially for supercritical drying
- DO NOT ATTEMPT TO WELD STAINLESS STEEL yourself, even if you have welded before-the stainless steels needed for a manuclave require special training and equipment to weld properly and an amateur weld will cause the pressure vessel to fail catastrophically
Okie doke! Now let’s get started!