Floating roof
Floating roof means a roof that floats on the surface of the liquid in a storage vessel. A floating roof substantially covers the stored liquid surface (but is not necessarily in contact with the entire surface), and is comprised of a deck, a rim seal, and miscellaneous deck fittings.
Source
40 CFR § 63.1061
Scoping language
All terms used in this subpart shall have the meaning given them in the Act and in this section.