Non-enclosed process
Non-enclosed process means any equipment system (such as an open-top reactor, storage tank, or mixing vessel) in which a chemical substance is manufactured, processed, or otherwise used where significant direct contact of the bulk chemical substance and the workplace air may occur.
Source
40 CFR § 721.3
Scoping language
The definitions in section 3 of the Act, 15 U.S.C. 2602, and 720.3 of this chapter apply to this part. In addition, the following definitions apply to this part: