The Clean Air Act 1993 introduced a wide range of new regulations to include the control of smoke emissions, the height of chimneys and the content and composition of motor fuels. Under certain conditions we must approve chimney height.

Dark Smoke

It is an offence to cause or permit the emission of dark smoke from a chimney or flue at industrial or trade premises. This also applies to burning materials on a site that you own or a site where you are working such as a building or demolition site, or land used for commercial agriculture or horticulture.

We do not have to witness the emission of dark smoke to take action; evidence of the burning of materials that potentially give rise to dark smoke is sufficient. This way the law aims to stop people creating dark smoke at night and using the lack of visual evidence as a defence.

Smoke Control Areas

These are intended to control pollution in areas where the predominant fuel used for domestic heating is coal. There are currently no smoke control areas in Mid Devon.

Chimney Heights

The control of chimney heights enables us to take into account a number of relevant factors in determining the height of a chimney. Under section 14 of the Clean Air Act 1993, unless the height of the chimney has been approved by the local authority and any conditions attached to approval adhered to, it is an offence to cause, or knowingly permit a boiler/furnace to be used to:

  • burn pulverised fuel;
  • burn at a rate of 45.4 kg or more an hour, any other solid matter; or
  • burn at a rate equivalent to 366.4 kW or more, any liquid or gaseous matter


An application for chimney height approval must contain adequate information to enable the necessary calculations to be carried out. See Industrial Chimney Height Approval Form to download an approval form.

We must consider any application for approval for chimney height for a furnace and give a written decision within 28 days of receipt, unless it is agreed in writing between us and the applicant that a longer period is allowed. If we fail to deal with the application within this time period, then approval without qualification is given.

Please note that any new boiler may require planning permission and you should submit a planning application alongside your application for chimney height. Please see our Planning webpages for more information on planning applications.

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