MineArchiveMaerdy Colliery explosion, 1885
An explosion in the North West dip workings at Maerdy Colliery on 23 December 1885 killed around 76-81 men, with roughly 750-961 men underground at the time.
| Date | 23 December 1885 |
|---|---|
| Mine | Maerdy Colliery |
| Region | Rhondda Cynon Taf |
| Type | Explosion |
| Fatalities | 76 (NMRS's dedicated accident page records 76 deaths (70 dead at the scene, 6 rescued alive but died later of injuries) and 7 injured survivors; Wikipedia separately gives 81 deaths (63 from suffocation, 18 from burns and blast violence). Victims ranged in age from 12 to 66. Both figures are recorded rather than reconciled.) |
| Context | During active mining |
Cause
Two competing contemporary theories were advanced: a naked-flame 'comet' lamp igniting coal dust raised by a blown-out shot in a stone heading, or firedamp accumulated in a cavity above masonry arches ignited when a mason raised a naked lamp into the gas. The inquest jury found insufficient evidence to settle which was correct, though the investigating barrister concluded that whatever the ignition source, the profusion of coal dust in the workings was what actually propagated the explosion.
What happened
The explosion struck around 2:40pm on 23 December 1885 in the North West dip workings.
Rescue & recovery
The mine's ventilation fan kept running throughout, allowing an immediate rescue effort; the agent and manager descended promptly and ventilation and afterdamp clearance was restored within about three hours.
Investigation & inquiry
Barrister A. G. C. Liddell's inquiry found poor compliance with the Coal Mines Regulation Act 1872 — no visible barometers at the mine entrance, naked-flame lamp stations throughout the workings, and inadequate coal-dust watering.
Legal & regulatory aftermath
The jury's recommendations led toward mandatory systematic dust-watering and shot-firing regulation, and included a call for safety instruction for schoolchildren in colliery districts.
What's uncertain
Points where sources disagree or the record could not be settled; both accounts are kept. All open questions in the archive.
- NMRS's dedicated accident page gives 76 deaths; Wikipedia separately gives 81. Both figures are recorded rather than reconciled. (disputed) 1,2
Recorded claims
Individual factual claims, each attached to the source(s) that support it below. Where sources disagree, both are kept.
- NMRS's dedicated accident page gives 76 deaths; Wikipedia separately gives 81. Both figures are recorded rather than reconciled. (disputed) 1,2
Related terminology
Mining terms this disaster is structurally linked to, with the nature of the relationship.
- Afterdamp (contextual relationship)
Named in this record’s rescue and recovery: “…effort; the agent and manager descended promptly and ventilation and afterdamp clearance was restored within about three hours.” - Coal (contextual relationship)
Named twice in this record, first in the cause: “…theories were advanced: a naked-flame 'comet' lamp igniting coal dust raised by a blown-out shot in a stone heading, or firedamp…” - Firedamp (contextual relationship)
Named in this record’s cause: “…igniting coal dust raised by a blown-out shot in a stone heading, or firedamp accumulated in a cavity above masonry arches ignited when a mason…” - Naked Light (contextual relationship)
Named twice in this record, first in the cause: “Two competing contemporary theories were advanced: a naked-flame 'comet' lamp igniting coal dust raised by a blown-out shot in a…” - Shot-firing (contextual relationship)
Named in this record’s aftermath: “…recommendations led toward mandatory systematic dust-watering and shot-firing regulation, and included a call for safety instruction for…”
Sources
- (secondary) Mardy Colliery — Wikipedia
- (secondary) Mardy Colliery Explosion — Rhondda Valley — 1885 — Northern Mine Research Society
Record created: 26 August 2026 · Last researched: 26 August 2026