What is the difference between the "General" and "One-Time" approval?

General or laboratory approval is generally for identical mass produced equipment with a one-year approval time, after which a re-evaluation would be required for another one-year period, if the applicant would like to maintain approval.

One-Time approval is for field installed product(s) at a specific location. The approval for the product is limited to the location in which it's installed, but no annual renewal is required, as is the case of general approval.