BAT (best available technology)

BAT stands for Best Available Technology (also rendered Best Available Techniques). It is the principle that pollution control should be based on the most effective and advanced methods that are technically proven and economically practical for an industry — not the cheapest possible method, and not an unaffordable ideal, but the best workable standard. Regulators invoke BAT when setting consent conditions and when judging whether a plant's control measures are adequate.

The concept embeds a deliberate balance. "Best" means most effective at reducing pollution; "available" means commercially obtainable and demonstrated at scale, not experimental; and implicit is "economically achievable" for the sector. BAT evolves over time — as cleaner technologies mature and become affordable, the BAT benchmark rises, so a control system that was BAT a decade ago may no longer qualify.

For recyclers, BAT is the yardstick the SPCB may apply when prescribing or upgrading pollution-control requirements. For effluent, BAT might mean a properly engineered ETP with biological plus tertiary treatment, or zero liquid discharge in water-stressed areas. For air, it might mean a baghouse rather than a cyclone alone, alkaline scrubbing of acid gases, and afterburning of pyrolysis off-gas. For process, it points to inherently cleaner choices — the membrane cell over the mercury cell for caustic soda is a textbook BAT example.

The practical implication is to design and upgrade control systems to a recognised good-practice standard rather than the bare minimum, because BAT-based conditions can be imposed at consent renewal and BAT is the standard against which boards and the NGT judge whether an operator was negligent. Specifying BAT-grade controls also future-proofs a plant against tightening norms and reduces the risk of forced, costly retrofits later.