There’s only one solvent which the state of Oregon has seen fit to not to legislate at any level, thats CO2. We imagine it’s great peace of mind knowing that even if post-processing was disturbed that there is never any safety risk to consumers.
Now safety is important, but its not the only area where supercritical CO2 far outperforms traditional alternatives. The tunable properties of supercritical CO2 allow for the most selective extraction, meaning higher concentrations of active compounds and more precise fractionation. Beyond its standard competitors, CO2 is the laboratory standard for precise fractionation as evidenced in this article from the Journal of Separation Science.
As far as facility safety is concerned, you’d most likely use CO2 to put out the fires started by more dangerous hydrocarbon or alcohol liquid solvents. As with all compressed gasses, there are some physical risks which can be avoided by following these guidelines.