As used in this part:

(a) Manufacturer means any person who re-refines or otherwise processes used oil to remove physical or chemical impurities acquired through use or who blends such re-refined or otherwise processed used oil with new oil or additives.

(b) New oil means any synthetic oil or oil that has been refined from crude oil and which has not been used and may or may not contain additives. Such term does not include used oil or recycled oil.

(c) Processed used oil means re-refined or otherwise processed used oil or blend of oil, consisting of such re-refined or otherwise processed used oil and new oil or additives.

(d) Recycled oil means processed used oil that the manufacturer has determined, pursuant to section 311.4 of this part, is substantially equivalent to new oil for use as engine oil.

(e) Used oil means any synthetic oil or oil that has been refined from crude oil, which has been used and, as a result of such use, has been contaminated by physical or chemical impurities.

(f) Re-refined oil means used oil from which physical and chemical contaminants acquired through use have been removed.