Report on the causes of, and circumstances attending, the explosion which occurred at Chanters Colliery, Lancashire, on 6th March, 1957.

8th October, 1957.

In accordance with your direction, given under the terms of Section 121 of the Mines and Quarries Act, 1954, I have the honour to submit my report on the causes of, and circumstances attending, the explosion which occurred at Chanters colliery, Lancashire, at 3.50 p.m. on 6th March, 1957, when four persons were killed outright and four others were so seriously burned that they died later.

On 25th July, 1957, Mr. R. M. Barlow, H.M. Coroner of the County of Lancaster, Bury District, held an adjourned Inquest at Tyldesley on the bodies of the eight victims of the explosion. A verdict of "Misadventure" was recorded in each case.

My investigations showed that the explosion was caused by an electric arc which was formed during an examination of the working of a switch to which power was still connected, when the top cover of the switch was twisted around and came into contact with a live busbar, in the presence of a body of inflammable gas.

Chanters colliery is situated within the township of Atherton, about ten miles to the west of Manchester. The downcast shaft, No. 1,14 feet in diameter, was sunk in 1850 and deepened to the Arley seam at the depth of 600 yards in 1901; the upcast, No. 2, 16 feet in diameter, was sunk to the Rams seam in 1876 and was finally deepened to the Arley in 1902.

The mine, has been extensively worked in the past and most of the best seams have been extracted. At present, the Five Quarters, Victoria, Haigh Yard and Plodder seams are being worked. The Haigh Yard and Plodder are wound at No. 1 shaft from the depth of 489 yards, approximately the level of the Haigh Yard seam, whilst the Five Quarters and Victoria are raised in skip plant at No. 2 shaft from the depth of 345 yards, a level intermediate between the Victoria and Plodder seams. The average daily saleable output for the mine is 1,870 tons, of which 75 tons is from the Plodder seam, the one in which the explosion occurred; the total number of persons employed is 1,318, of whom 1,043 work underground.

The owners of the colliery are the National Coal Board. The manager is Mr. G. F. Hiller and there are two under-managers, Mr. J. Haslam for No. 1 pit workings and Mr. J. Charlton for No. 2 pit. The electrical engineer for the mine is Mr. J. Benjamin.

The mine is in No. 2 (Wigan) Area of the North Western Division of the National Coal Board. Under Section 1 (1) of the Mines and Quarries Act, 1954, written instructions have been given to several persons by the National Coal Board for securing the fulfilment of the Board's statutory responsibilities. Among these are

There is no record of an explosion having occurred at the mine previously. None of the seams now being worked is particularly gassy, probably because the beds have been drained to some extent by the earlier workings. The limited experience so far obtained in the Plodder seam shows that it has a gas yield of approximately 110 cubic feet per ton of coal mined. Safety lamps, permitted explosives and electricity are in use throughout the mine. For general lighting purposes Oldham-Wheat G.W. electric cap lamps are provided; Prestwich Patent Protector Type 6 relighter lamps are used by deputies and senior officials and Protector MC 40 lamps are issued as gas detectors to certain appointed workmen. Although automatic gas detectors are not required to be provided by statute on any of the faces, some 20 Naylor Spiralarm Type M detectors are in use in No. 2 pit.

The fan at No. 2 shaft is an electrically driven double inlet Sirocco, 98 inches in diameter, revolving at the speed of 231 revolutions a minute and producing just less than 200,000 cubic feet of air per minute in the fan drift at a water gauge of 41 inches.

After having worked for well over 100 years, Chanters colliery, in common with a number of its neighbours, is approaching the end of its useful life. It is not unexpected that through the reorganisations which have affected the coalfield over the last decades, opportunity should have been taken to effect some concentration of the remaining workings of these collieries. The concentrations have usually been for the purposes of ventilation and have affected Chanters and its neighbours to a somewhat unusual extent.

Whenever a connection is made between two mines and part of the ventilation system is common to both, the two mines cannot be deemed to be separate mines without the permission of the Inspector of the Division and in accordance with such conditions as he may prescribe. Following the making of a new connection between Chanters and St. George's collieries in 1941, a new Instrument was drawn up by my predecessor, the late Mr. E. H. Frazer, O.B.E., on 1st August, 1941, under Section 25 (1) of the Coal Mines Act, 1911, which superseded some earlier Instruments of smaller scope, consenting to the five mines, viz. Nook, St. George's and Gin, Chanters, Bedford and Gibfield, being divided into five parts and being worked separately notwithstanding that each part did not have a separate system of ventilation. All these mines, with the exception of Gin pit, are still in operation and are still interconnected; coal is not now drawn at St. George's but it is continuing its life as one of the training pits for No. 1 (Manchester) Area. The connections between the mines which have a bearing on the explosion are shown on Plate I, the detached illustration in the pocket at the back of this Report.