Duncan Explosion 1977

07/02/1977 - Duncan Colliery - Explosion / Methane Explosion

At approximately 9:02 am on Monday, 7th of February 1977 a small weak methane explosion occurred near a development face at Duncan Colliery, near Cornwall, Tasmania. The methane accummulated near the development face over a long weekend due to inadequate ventilation and booster fans which had been turned off due to being too noisy.

The accumulation of methane was not detected by the deputy:

  • Who had been allocated other work which forced him to rush his inspection,
  • Suffered from a lack of training resulting in the deputy not appreciating the gravity of the situation,
  • He had a lack of practical experience (and may have left the cap on the methanometer),
  • Had a lack of knowledge of the properties of methane,
  • May have missed the accumulation of gas due to a relatively small quanity.

Cigarettes and matches were being carried by the deceased persons. A spent match head was found at the source of the explosion.

This accident claimed the lives of 3 people.


  • To elininate fire risk rubbish, waste and inflammable matertal to be removed fron the mine.
  • No person other than a competent person appointed by the Manager in writing shall operate mechanical ventilating equipment at the mine.
  • Where a build up of methane occurs all productive work will cease if the percentage in the general body of air exceeds 1.25% CH4. Power is to be shut off and all men withdrawn if the % exceeds 2.5%.
  • Everyone who works underground in the mine must ahve knowledge of the properties of methane gas and the safey measures to take in dealing with it.
  • A barometer is required to be provided at the entrance to the mine and barometric pressure readings are to be recorded at teh commencement of each shift.