30 YEAR SECRET REPORT INTO MOURA No 4 Chapter 4 IGNITION SOURCE FOR THE MOURA EXPLOSION
CHAPTER 4
IGNITION SOURCE FOR THE MOURA EXPLOSION
By
- Golledge, I. Roberts
4.1 Fire or Spontaneous Combustion
4.1.1 Roadways and Cut- Throughs
A fire occurred in 24 c/t between No.2 Transformer Road and No. 3 Belt Road but was considered to be the result of the explosion. The belt road was inspected by Mr Bayles and Mr Foden prior to the explosion, however, no evidence Of a fire was noted.
4.1.2 Goaf Area
Carbon monoxide levels recorded on the continuous monitoring system in the Main Pips Section return airways were low prior to the explosion and there was no evidence of any build up of carbon monoxide due to a spontaneous heating.
4.2 Electrical Apparatus and Cables
4.2.1 Apparatus
A Comprehensive examination of all electrical apparatus underground was carried out by Electrical Inspector of Coal Mines Mr A. McMaster with the ass istan ce of Senior Inspector Electrical Testing Mr T.G. Hislop (SIMTARS).
The underground telephone system voltage and currents were tested and found to be within the required values. The high voltage protection system . was also found to be satisfactory. An in-situ examination was made of the substation and the fault protection system was later checked’ at the surface, together with the faces of doors and other fittings. No faults were found. The remote control for the belt conveyor was removed for subsequent intrinsic safety testing at SIMTARS and was found to be operating safely. All electrical enclosures in the section were carefully examined to check on the gap at the flameproof flange and for any signs of any internal ignition within the enclosure. For each enclosure the gap was well below the maximum allowed in the relevant Australian Standard.
