Future EU air legislation
Historically, environmental legislation has been driven by either ‘available technology’ or ‘environmental quality’. In the former approach, available technology is applied to progressively reduce emissions of the pollutants of concern. It implies that a common solution is required within the geographical scope of the legislation (e.g. the EU). The process involves an assessment of the capability of available abatement technologies to derive an emission limit which is then enshrined in legislation. In effect this emission limit becomes a surrogate for the chosen technology or technologies. Since, in this case, the only definition of ‘clean’ is zero emissions, progressive updates of the legislation, with tougher emission limits, are made at regular intervals to reflect the developments in available technology. Concepts like the application of Best Available Techniques, sometimes embracing the notion of ‘Not Entailing Excessive Costs’, are derived from this approach.