Grassmoor Colliery Explosion, 1933

Firedamp exploded on a ninety-yard conveyor face in the Deep Hard seam at Grassmoor's No. 8 pit just before two on a Sunday morning, killing fourteen of the eighteen men at work there. The source of ignition was never established, an electric cap-lamp headpiece being the likeliest suggestion, and a public inquiry was held under the Coal Mines Act.

Cause

An explosion of firedamp on a conveyor face in the Deep Hard seam. The cause of ignition was never established with certainty; the Durham Mining Museum's summary records it as uncertain and possibly an electric cap-lamp headpiece.

Contributing factors

The coal had been undercut during the afternoon shift on the Saturday, and the men were extending the packs and moving the conveyor pans forward when the gas fired. Nothing was found about the drilling machine that could have caused ignition; no shots had been fired and there was no evidence of smoking or matches, and no evidence that a pick or other tool striking the ironstone balls in the soft bind roof had ever made a spark.

What happened

Just before two o'clock on the morning of Sunday 19 November 1933 firedamp exploded in the Deep Hard seam at the No. 8 pit of Grassmoor Colliery, on a conveyor face about ninety yards long. Eighteen men were working on the face. Fourteen were killed. The coal had been undercut on the Saturday afternoon shift and the men were extending the packs and moving the conveyor pans forward at the time.

Rescue & recovery

His Majesty's Inspectors of Mines began investigating the same day. Prince George, who was staying at Chatsworth, came to the district to convey the sympathy of the King and Queen to the families of the dead.

Investigation & inquiry

The Secretary for Mines, Ernest Brown, made a statement to the House of Commons on 22 November 1933 in answer to a private notice question from Mr Conant, and announced that a public inquiry would be held by the Chief Inspector of Mines under section 83 of the Coal Mines Act 1911. Members pressed him on whether the lamps in use had been oil or electric and on whether the time had come for miners to be given an automatic gas alarm; he would not be drawn before the circumstances had been examined. The inquiry opened in the council chamber of the Stephenson Memorial Hall, Chesterfield, on 13 December and finished on 16 December, and Sir Henry Walker, HM Chief Inspector of Mines, presented his report in March 1934.

Legal & regulatory aftermath

No prosecution is recorded in the sources read. The inquiry could not fix the source of ignition.

Changes to practice & legislation

The exchange in the Commons two days after the explosion turned immediately on lamps and on whether miners should be given automatic gas alarms, which is where the argument about detecting firedamp stood in the 1930s.

Memorials & commemoration

None found.

Recorded claims

Individual factual claims, each attached to the source(s) that support it below. Where sources disagree, both are kept.

• An explosion occurred in the Deep Hard seam at No. 8 pit just before two o'clock on the morning of Sunday 19 November 1933, on a conveyor face about 90 yards long; of the 18 men at work on the face, 14 were killed and 4 injured. ¹
• A local history of the colliery gives eight men injured rather than the four reported to the Commons. (disputed) ²
• The cause of ignition was uncertain, the Durham Mining Museum recording it as possibly an electric cap-lamp headpiece. (uncertain) ³
• The Secretary for Mines announced on 22 November 1933 that a public inquiry would be held by the Chief Inspector of Mines under section 83 of the Coal Mines Act 1911. ¹
• Prince George, staying at Chatsworth at the time, came to the district to convey the sympathy of the King and Queen to the families of the victims. ²

Related terminology

Mining terms this disaster is structurally linked to, with the nature of the relationship.

• Coal (contextual relationship)
  Named twice in this record, first in the contributing factors: “The coal had been undercut during the afternoon shift on the Saturday, and…”
• Coal Mines Act 1911 (contextual relationship)
  Named in this record’s investigation: “…be held by the Chief Inspector of Mines under section 83 of the Coal Mines Act 1911. Members pressed him on whether the lamps in use had been oil or…”
• Colliery (contextual relationship)
  Named in this record’s narrative: “…exploded in the Deep Hard seam at the No. 8 pit of Grassmoor Colliery, on a conveyor face about ninety yards long. Eighteen men were…”
• Firedamp (direct cause)
  Firedamp exploded on the conveyor face in the Deep Hard seam; what lit it was never established.
• HM Chief Inspector of Mines (rescue/recovery concept)
  The public inquiry was held by the Chief Inspector of Mines under section 83 of the Coal Mines Act 1911, and Sir Henry Walker reported in March 1934.

Sources

1. (primary) Grassmoor Colliery Disaster: statement by the Secretary for Mines, House of Commons, 22 November 1933 (Hansard, HC Deb vol 283 cc85-6) — UK Parliament
2. (secondary) Grassmoor Collieries (oldminer.co.uk) — oldminer.co.uk (Andrew Bridgewater)
3. (secondary) Durham Mining Museum: Grassmoor Colliery — Durham Mining Museum

Record created: 9 September 2026 · Last researched: 9 September 2026