Air

SEPA is responsible for implementing the following directives in Scotland:

• Large Combustion Plants 
  Setting out a monitoring plan for all plants greater than 50MW capacity and emission limits for sulphur dioxide (SO2) and oxides of nitrogen (NOx).
  
  
• Sulphur Content
  Limiting the concentration of sulphur compounds allowed in diesel fuel and gas oils, in order to reduce air pollution.
  
  
• Combating Air Pollution from Industrial Plants
  This directive follows the ‘best available technology not entailing excessive costs’ (BATNEEC) principle in relation to major industrial plant (eg asbestos, glass fibre manufacturers, steel plants, power stations) and the intention that pollution should be minimised for a specific range of substances (eg hydrocarbons, heavy metals, chlorine).
  
  
• Municipal Waste-Incineration Plants 
  Providing limit values for gaseous temperatures and dust content and carbon monoxide concentrations in the emission.
  
  
• Sulphur Dioxide and Suspended Particulates
  Prescribing sampling and analysis methodologies and limits and values for atmospheric concentrations. Similar requirements are made under the Nitrogen Dioxide, Ozone and Lead directives.
  
  
• Petrol Vapour Recovery
  Requiring all new and existing petrol filling stations to minimise the vapours escaping during handling of vehicle fuels.
  

The World Health Organization (WHO) also publishes guideline values for acceptable atmospheric concentrations of ozone, radon, lead, nitrogen dioxide, sulphur dioxide, and particulates.