Acetylene Lamp

A portable lamp burning acetylene gas, generated inside the lamp by dripping water onto calcium carbide, giving a bright, unenclosed flame; used underground as an alternative to candles and oil-wick lamps, but -- unlike a safety lamp -- with no wire gauze or other means of containing its flame.

Historical usage

Used underground at Wernbwll Colliery, Penclawdd, as the mine's standard naked-light source (alongside some candles) until a firedamp explosion in September 1928 led to Special Regulations requiring flame safety lamps in prescribed places in addition to the acetylene lamps already in general use. The official report into the mine's second, fatal explosion, in November 1929, concluded that the flame of an open acetylene lamp had ignited the firedamp that killed seven men.

How it worked

The lamp's two chambers were filled separately: water in an upper chamber, calcium carbide in a lower one. A controllable drip fed water onto the carbide, producing acetylene gas as the two reacted; the gas was piped to a burner and lit with a match or a built-in striker, and a reflector behind the flame directed the light. More water dripped onto the carbide produced more gas and a bigger flame.

Why it was used

An acetylene lamp burned cleaner and brighter (some four to six candlepower) than the candles and oil-wick lamps it replaced, and produced less carbon monoxide and consumed less oxygen than either. Where a mine's officials judged firedamp risk low enough not to require enclosed safety lamps throughout, the acetylene lamp's open flame was cheaper to run and gave far better light than an enclosed safety lamp could.

Risks & limitations

Because its flame was unenclosed, an acetylene lamp could ignite firedamp directly, as the official inquiry into the 1929 Wernbwll Colliery explosion concluded had happened there. A typical cap lamp ran for only about four hours before needing a carbide refill, its burner tip was prone to clogging, and its flame could be blown out by a concussive blast or a draught. Acetylene lamps were mostly superseded by electric cap lamps from around 1918 and had been almost entirely replaced in general use by the 1930s, though the open acetylene lamp documented at Wernbwll in 1929 shows naked lights of this kind remaining in ordinary underground use well after that date, in mines whose officials judged the firedamp risk low.

Regional variation

The Smithsonian sources used here describe American design and manufacturing history; British sources consistently call the lamp an 'acetylene lamp' rather than the more common American term, 'carbide lamp', kept here as an alias.

Related terminology

Safety Lamp

Mines associated with this term

Included only where MineArchive's own research gives a reasonable evidential basis — not every mine where this might plausibly apply.

• Clydach Merthyr Colliery — Swansea (well documented example)
  Named in this record’s summary: “…with five to six hundred men. Almost free of gas, it was worked with carbide lamps and had boilers and a smithy underground; coal stopped in 1961, and…”
• Louisa Colliery — County Durham (well documented example)
  Named in this record’s history: “…it, the Louisa, William and Morrison North. A fire caused by an acetylene lamp in the Low Main seam in 1929 forced the sealing of about 100 acres…”
• Oakerdykes Pit — Falkirk (well documented example)
  Named 3 times in this record, first in the summary: “…for over forty years. Too small to be nationalised, it was lit by carbide lamps in a seam free of gas, and closed in August 1978 when one of the…”

Disasters associated with this term

Included only where MineArchive's own research gives a reasonable evidential basis, with the nature of the relationship stated — not every disaster where this term might plausibly apply.

• Wernbwll Colliery explosion, 1929 (direct cause)
  The official inquiry concluded the flame of an open acetylene lamp ignited the firedamp that caused the explosion.
• Louisa Colliery explosion, 1947 (contextual relationship)
  Named in this record’s narrative: “…a serious fire in the Low Main seam in 1929 had been caused by an acetylene lamp. The 4th North District, where the explosion happened, lay within…”

Sources

1. (primary) Wernbwll Colliery Disaster Report (H.M. Inspector of Mines) — Durham Mining Museum (official inquiry report)
2. (secondary) Carbide Lamps (Mining Lights and Hats) — Smithsonian Institution
3. (secondary) Miner's Carbide Lamp — Smithsonian National Museum of American History
4. (secondary) Wernbwll Colliery Explosion - Penclawdd - 1929 — Northern Mine Research Society

Record created: 14 September 2026 · Last researched: 14 September 2026