The nuisance caused by smoke from a domestic property or non-dark smoke from an industrial or trade premises would be considered a statutory nuisance by the Environmental Health Section.
There may also be implications under waste management regulations if the material being burnt is waste and you may also wish to contact Natural Resources Wales on 0300 065 3000 (Monday to Friday, 9am to 5pm).
The Clean Air Act 1993 makes it an offence to emit dark smoke from the chimney of any building. If found guilty of such an offence, the occupier of a dwelling could be liable to a fine of up to £1,000, or £5,000 in the case of a person having possession of a furnace of a boiler or industrial plant.
In addition, it is also an offence to cause dark smoke to be emitted from any industrial or trade premises. This provision relates to smoke from Bonfires. Trade premises can include farms and demolition sites.
These offences are subject to certain exemptions and do not apply to an activity which has a permit under regulations under section 2 of the Pollution Prevention and Control Act 1999.
Similar provisions relate to railway engines and water going vessels.
Any person who causes or permits the emission and is found guilty of an offence, could be liable to a fine of up to £20,000.
The council may consider that an offence of dark smoke has been committed if it finds evidence of plastic, tyres or chipboard in the remains of a bonfire. Cable burning is a specific offence under section 33 of the Act and is subject to a fine of up to £5,000.
How to measure dark smoke
Dark smoke can be measured using the Ringelmann Chart.
A Court may be satisfied that smoke is or is not dark smoke even if there has been no comparison with a Ringelmann Chart.