Press release

Report 01/2020: Serious operational irregularity at Balham

RAIB has today released its report into a serious operational irregularity at Balham, 20 April 2019.

Photograph showing trackwork looking south west of Balham station

Trackwork looking south-west of Balham station


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At around 19:05 hrs on Saturday 20 April 2019, a tamper, a self-propelled piece of on- track machinery, made an unsignalled and unauthorised move of about 600 metres, passing over Balham Junction, and entering platform 3 at Balham station, south London. The tamper could potentially have collided with a passenger train, which had travelled over the same junction in the opposite direction around 75 seconds earlier. The tamper stopped in the station, when the on-board crew realised that it was in the wrong place. There was no damage or personal injury.

The incident happened at the boundary of an engineering possession, where lines were closed for maintenance purposes. The plans for train movements out of the possession required the tamper, which had been working on the down line, to be crossed over to the adjacent up line while it was still inside the area under possession, and leave the possession on the up line. The crossing over move did not take place, and the tamper left the possession on the wrong line.

This happened because the person in charge of the possession (PICOP) provided incomplete information about the position of the tamper; the tamper driver and conductor driver did not query the instructions provided by the PICOP; and two signallers did not query the instructions provided by another PICOP. The standard of safety critical communications was poor throughout, resulting in no party having a clear understanding of the location of the tamper or the actions to be taken, and Network Rail’s management of the PICOP role has been ineffective. Underlying factors were that the labour supplier which employed the PICOPs had not effectively managed its own policy on monitoring safety critical communications, and that Network Rail’s strategy for improving and maintaining the standard of safety critical communications within the rail industry has been ineffective, and has not changed the work force culture or secured the adoption of good practice in respect of communications with and between signallers and other operations staff.


RAIB has made four recommendations, all addressed to Network Rail. The first calls for a review of the company’s strategy for safety critical communications involving its staff and contractors, to address underlying cultural factors and embed the use of standard communication protocols within the railway industry. The second covers a review of the process of handovers between signallers, during and at the end of shifts, to produce a structure which will give the incoming signaller full awareness of all relevant information about the location and intended movement of trains. The third recommendation relates to the provision of a suitable working environment for PICOPs, and the fourth to a review of that role, including the competency requirements and ongoing professional management of PICOPs. Two learning points relate to the need to test staff involved in safety incidents for drugs and alcohol, and the importance of not using mobile phones while driving road vehicles.

Simon French, Chief Inspector of Rail Accidents said:

Yet again we have investigated an incident in which a poor standard of communications played a crucial part. In this case, the way in which the key individuals talked to each other resulted in a misunderstanding. The consequences of the misunderstanding were that a very large item of yellow plant, a tamping machine, came out of an area where it had been working, onto a line where a passenger train had passed in the opposite direction only a short time before.

The role of person in charge of a possession (PICOP) is an important one. The PICOP controls the movement of trains into, within and out of engineering possessions. There were ten trains working in the possession near Balham, and giving their drivers clear and correct instructions is a vital job. It is not something that should be done from a kitchen table, or while driving a car. PICOPs need to be given adequate facilities for their work, and should make proper use of them.

Our investigation found a culture of poor communications among staff involved with engineering work. People were embarrassed to use the proper protocols when passing messages to colleagues. The aviation industry confronted this problem head-on many years ago, and now any pilot or air traffic controller who does not use the correct form of words and phrases would instantly stand out as less than competent. We found that, while train drivers and signallers have generally achieved a good standard of safety critical communications in recent years, the same cannot be said for engineering operations staff, even when talking to signallers. We are challenging the railway industry to come into line with aviation, and embed the same standards among its people.

In this case several of the people involved did not challenge information or instructions which were confusing, inconsistent with what they had just been told by someone else, or contrary to rules. This is not the first time this has led to trouble, and the consequences can be disastrous. In the collision between two engineering trains in a possession at Logan in 2015, a locomotive and eighteen wagons were derailed and damaged. That accident also arose from a misunderstanding created by poor communications report 13/2016, and we have investigated other collisions in possessions at Badminton report 30/2007, Leigh on Sea report 24/2009, Arley report 12/2013 and Kitchen Hill bulletin B1/2014.

These are all areas in which the industry has previously made efforts to improve, but for whatever reason, lasting change has not happened. I hope that this time implementation of our recommendations will make a real difference.

Notes to editors

  1. The sole purpose of RAIB investigations is to prevent future accidents and incidents and improve railway safety. RAIB does not establish blame, liability or carry out prosecutions.
  2. RAIB operates, as far as possible, in an open and transparent manner. While our investigations are completely independent of the railway industry, we do maintain close liaison with railway companies and if we discover matters that may affect the safety of the railway, we make sure that information about them is circulated to the right people as soon as possible, and certainly long before publication of our final report.
  3. For media enquiries, please call 01932 440015.

Newsdate: 3 February 2020

Published 3 February 2020