Even after its construction and commissioning, an installation requiring a permit must always be operated in compliance with the basic obligations under Section 5 BImSchG and the statutory orders based on Section 7 BImSchG, i.e. in particular in accordance with the state of the art. For this purpose, concretising official orders may be issued (cf. § 17 BImSchG).
Pursuant to § 3 para. 6 BImSchG, the "state of the art" is understood to mean the state of development of advanced processes, equipment and modes of operation by which
- emissions to air, water and soil are limited,
- plant safety and environmentally sound waste disposal are ensured, and/or
- otherwise avoid or reduce impacts on the environment.
For installations under the Industrial Emissions Directive, the so-called Best Available Techniques (BAT) are taken into account, the state of which is continuously updated and defined at European level. The aim of operating installations according to the state of the art is to achieve a generally high level of protection for the environment.
The competent authority (usually the district administrative authority) may also order the operator to have the type and extent of the emissions emitted by the installation and the immissions in the area affected by the installation determined by a notified body (§§ 26, 28 BImSchG). A prohibition of operation is possible, inter alia, if the operator does not comply with a condition, a subsequent order or a material requirement or if the permit is missing (§ 20 BImSchG). It should be noted that a granted permit may be revoked under certain conditions (§ 21 BImSchG).