In the publication, Cannock Chase Coalfield and its Coal Mines, produced by the CCMHS around 2006 (page 160) there is a reference to an accident at Walsall Wood Colliery in March of 1890, which involved injuries and a fatality. There is a youth referred to as the cause.
If you look at the Inquest the youth, Bradbury, was in no way to blame....A discussion of this accident can be seen here on Brownhills Bob's Blog...
http://brownhillsbob.com/2014/04/27/vapour-trials/