Protecting the environment is a regional competence in Belgium. The legal basis for fighting the environmental pollution from industrial installations in Flanders is regulated in title I and II of VLAREM. Both are implementing orders of the environmental pollution decree of 28 June 1985.

VLAREM decides that the operator, being a normal, careful person, uses the best available techniques at any time in order to protect people and the environment. This both for the choice of emission treatment options as for the choise of prevention measures (adapted production techniques- and methods, controlling raw materials and so on). This obligation concerns changes in installations as well as activities that acquire no permit. Complying with conditions of VLAREM and/or of the environmental permit are expected to agree (chapter 4.1.2 of title II of VLAREM).

VLAREM also determines that the emission limit values, the parameters and the equivalent technical measures should be based on the best available techniques without imposing a certain technique or technology. Technical characteristics, the geographical situation and the local environmental circumstances of the concerned installation should be taken into account. If, in order to reach environmental quality goals, more severe conditions are needed than those achievable with BAT, additional conditions may be imposed (art. 30 bis of title I of VLAREM).