Guidance

Coal seams with a history of spontaneous combustion

Published 23 March 2015

The following tables presents a list of coal seams which have been known to suffer from occurrences of spontaneous combustion and are consequently regarded as at ‘high risk’ of succumbing to spontaneous combustion when being entered, worked or disturbed.

Coal seams which are excluded from the table should not be regarded as free from risk of spontaneous combustion as the majority of coal seams could suffer from spontaneous combustion depending upon the method of them being entered, worked or disturbed.

Please be aware that some areas may have localised names for these seams.

1. Coal Seams in England with a history of spontaneous combustion

Seam Location	Coal Seam
Cannock	Bass, EightFoot, Shallow
Cumberland	Where roof coal is left
Durham (South)	Maudlin, Seam
Lancashire	Where roof coal is left, Higher, Florida, Lower Florida, Trencherbone
Leicestershire	Lount Seam, Excelsior, New Main
Derbyshire (North)	Deep Soft, Top Hard
Derbyshire (South)	Main Coal
Northumberland	High Main, Main
Nottinghamshire	Blackshale, Top Hard, Top Soft, Parkgate, Low Main
Staffordshire (North)	Great Row, Spencroft, Cannel Row, Moss, Cockshead, Ten Feet
Staffordshire (South)	Staffordshire thick coal
Warwickshire	Warwickshire thick coal
Yorkshire	Barnsley, Top Soft, Day Bed, Dunsil, Beeston, Stanley Main, Shafton, High Hazel, Thorncliffe, Parkgate, Silkstone

2. Coal Seams in Scotland with a history of spontaneous combustion

Seam Location	Coal Seam
Ayrshire	Big Drum Seam, Coral Seam, Gas Water, Main Coal, Major Seam, Patna, Seven Foot Coal, Thick, Wee Drum
Scotland (North)	Dysart Main
Scotland (South)	Stairhead, Corbie, The Kelty Main (Kinrod), Free Craighead (Quarrelton Thick Coal)

3. Coal Seams in Wales with a history of spontaneous combustion

Seam Location	Coal Seam
North Wales	Where roof coal is left

4. Coal seams with high risk spontaneous combustion based on cross over temperature values

The following table presents a list of coal seams which laboratory tests indicated were at high or medium risk of spontaneous combustion. The designation of high or moderate risk is based wholly on cross-over temperature (COT) tests^{[footnote 1]}.

It must be emphasised that, unlike the list of seams prone to spontaneous combustion based on mining history (above), this list is largely based on small samples from seams. Where there are multiple samples the number is shown in brackets following the risk level. This second list should therefore be treated as having less weight than the first list, although still having a significant value.

Coal seams which are excluded from the table should not be regarded as free from risk of spontaneous combustion as the majority of coal seams could suffer from spontaneous combustion depending upon the method of them being entered, worked or disturbed.

Seam Location	Coal Seam	Spontaneous Combustion Risk
South Yorkshire	Two Foot	High
South Yorkshire	Best	High
South Yorkshire	Clod	High (3)
South Yorkshire	Little Flint	High/Medium (3)
South Yorkshire	Lower Clunch	High (2)
South Yorkshire	Lower New Mine	High/Medium (2)
South Yorkshire	Randle	High (2)
South Yorkshire	Two Foot (Residual Coal)	High (2)
South Yorkshire	Upper Clunch	High (3)

1. COT tests gradually heat coal in the presence of air until the temperature becomes self sustaining and the lower temperature that this occurs, the greater the risk of spontaneous combustion. Coal samples with COT’s of below 170°C are designated high risk and those up to 200°C medium risk. ↩