We can easily make things too complex to really care or we can get down to what works. The chart above makes this all sound really difficult so I like to get down to asking what works. Since the above post mentions Cole-Parmer and that silicone is the worst tubing to use, I wanted to do a bit more checking as the above info is complex but leaves out some things that I feel matter. Like what temperature and what pressure. Those have always seemed to be the primary questions on choosing tubing as I rarely work with any serious chemical hazards.
So if you want to get some simple info that is reasonably easy to read, I suggest trying this.
Go to the Cole-Parmer site:
Chemical Compatibility Database from Cole-Parmer
Scroll down to get the rating for silicone as it is the material mentioned as the worst. Then scroll down to set it for using either CO2 dry or wet or check both as the rating comes back the same.
Click "results" and you may find the same as I did. The rating for the worst tubing (silicone) is this:
B = Good -- Minor Effect,
slight corrosion or
We can make life hard or we can make it simple. For me, if the worst is still rated GOOD, I think I can live with using most any of the better rated types! But then it is still just a matter of personal choice as to which you want to use but I recommend using what is cheap and easy until I get better information.
As to the question of what is low or high pressure it is all depending on who and what we are talking about. Steam lines may be a couple thousand PSI but for me, if it reads on the low pressure gauge, I'm for calling it low?