Labeled. Equipment is labeled if there is attached to it a label, symbol, or other identifying mark of a nationally recognized testing laboratory:
(1) That makes periodic inspections of the production of such equipment, and
(2) Whose labeling indicates compliance with nationally recognized standards or tests to determine safe use in a specified manner.
29 CFR § 1910.399
Acceptable. An installation or equipment is acceptable to the Assistant Secretary of Labor, and approved within the meaning of this subpart S: