As I understand your question, you are trying to show that you are not essential so that you can collect unemployment in a state that uses the federal list of critical occupations to determine eligibility.  

Have you applied and been turned down? Then the unemployment agency should be able to point you to a source that shows you are essential. Otherwise, finding a list of nonessential occupations is something like finding a list of nondeductible medical expenses, like pistachios you eat while waiting to see your doctor.

On the other hand, maybe you are concerned that some tax practitioners are collecting unemployment when in fact they are essential, because they support first responders, healthcare workers and employees at the wastewater department. Not to mention, they do a lot of data entry for the IRS, a law enforcement agency. That might apply to some people who know how to use lower case.