BAT meaning in Governmental ?

The best available technology or best available techniques (BAT) is the technology approved by legislators or regulators for meeting output standards for a particular process, such as pollution abatement or pasteurization. Similar terms are best practicable means or best practicable environmental option. BAT is a moving target on practices, since developing societal values and advancing techniques may change what is currently regarded as "reasonably achievable", "best practicable" and "best available".

A literal understanding will connect it with a "spare no expense" doctrine which prescribes the acquisition of the best state of the art technology available, without regard for traditional cost-benefit analysis. In practical use, the cost aspect is also taken into account. See also discussions on the topic of the precautionary principle which, along with considerations of best available technologies and cost-benefit analyses, is also involved in discussions leading to formulation of environmental policies and regulations (or opposition to same).