Under Section 2 of the Air (Prevention and Control of Pollution) Act, 1981, Occupier means any person who has control over any industrial plant, and includes the owner or operator of the plant.

The occupier is responsible for ensuring that the industrial plant does not emit air pollutants in excess of the standards prescribed by the State Pollution Control Board (SPCB). The occupier must obtain prior consent from the SPCB before establishing or operating an industrial plant in an air pollution control area (Section 21), and must furnish information about any accident or pollution to the SPCB (Section 23).