R307-206-2. Definitions

  (1) The following additional definitions apply to R307-206:

  "Abrasive Blasting" means the operation of cleaning or preparing a surface by forcibly propelling a stream of abrasive material against the surface.

  "Abrasive Blasting Equipment" means any equipment utilized in abrasive blasting operations.

  "Confined Blasting" means any abrasive blasting conducted in an enclosure which significantly restricts air pollutants from being emitted to the ambient atmosphere, including but not limited to shrouds, tanks, drydocks, buildings and structures.

  "Multiple Nozzles" means a group of two or more nozzles being used for abrasive cleaning of the same surface in such close proximity that their separate plumes are indistinguishable.

  "Unconfined Blasting" means any abrasive blasting which is not confined blasting as defined above.