Test Before Touch for overhead line equipment

An essential requirement of any electrical system is a means of safely and efficiently disconnecting the system to allow maintenance work to take place, and not to create danger and the risk of injury.

Regulation 4 of The Electricity at Work Regulations 1989, requires that every work activity, including maintenance of a system and work near a system, shall be carried out in such a manner as not to give rise, so far as is reasonably practicable, to danger and the risk of injury. Regulation 14c also requires that no person shall be engaged in any work activity on or so near any live conductor where danger may arise unless suitable precautions are taken to prevent injury.

As a result of too many incidents of workers suffering life changing injuries due to inadvertent contact with Live Overhead Line Equipment (OLE), and the Office of Rail and Road (ORR) issuing an improvement notice (for non-compliance with regulation 14c), Network Rail are introducing a new standard “Test Before Touch for Overhead Line Equipment – NR/L3/ELP/27720”.

It was identified that Test Before Touch for OLE was not being carried out consistently and that life changing injuries would have been avoided if Test Before Touch had been carried out. The new standard was issued on the 3 September 2022 with a compliance date of 4 January 2023, and it formalises and improves on the existing guidance on the Test Before Touch Lifesaving Rule for OLE.

Consultation

Development of the new standard was undertaken after much consultation with the regions of Network Rail and learning from other railway infrastructure managers. Network Rail also talked to other industries which have similar electrical infrastructure, dangers, and risk of injury. An important aspect of any new safety process is that it must be practical and not too onerous to apply, otherwise there is a risk that it will not be implemented correctly. This was a key objective when developing the new standard.  

The authority to work on OLE is contained with the Overhead Line Permit to Work, known as a Form C and also referred to as the Overhead Line Permit (OLP). Undertaking a Test Before Touch action, or set of actions, using Live Line Indicators (LLIs) is the important final step in the OHL isolation process. It demonstrates to the Controller Of Site Safety – COSS(OLP) – and members of the working party that the OLE is de-energised at the location of the test, and this helps to confirm that the working party members are within the safe working limits of the OLP.

The standard provides information to enable Test Before Touch actions to be identified, implemented, witnessed, and recorded in a consistent manner. NR/L3/ELP/27720 only applies to OLE infrastructure, covering planned work, short notice work, and work following an emergency switch off.

A very important definition in the standard is that ‘touch’ or ‘touching a conductor’ is a task where it is planned for a person, tool, or item of equipment/plant to come within 600mm (2 feet) of an exposed conductor. If there is any uncertainty whether a task or task delivery method will result in an exposed conductor being touched, or coming within 600mm (2 feet), it must be assumed that this will happen and the standard followed.

A Test Before Touch action, or set of actions, will be implemented whenever an OLP is briefed and issued to a COSS (OLP) by a Nominated Person. A Nominated Person is someone who has been trained and certified competent to use LLIs and fully understand the dangers of working on and around the overhead line system. To ensure there is flexibility in order to facilitate all types of work on OLE, one of four methods of Test Before Touch will be selected by those responsible for planning the implementation of isolation(s) and associated OLP(s), and in each case the standard says how the method will be recorded and briefed.

Method 1: Dynamic decision making for Test Before Touch actions.

This method requires an Equipment Competent Person (ECP) to be part of the working party. The ECP determines and directs the Test Before Touch actions. This method is most likely to be selected for tasks and delivery methods such as high-level intrusive OLE maintenance, height and stagger adjustments, and OLE refurbishment / renewal.

Method 2: Pre-planned and pre-documented Test Before Touch actions.

This requires the Test Before Touch actions to be pre-planned, documented and subsequently endorsed by a person holding Nominated Person competence. It is most likely to be selected where there is no ECP in the working party, for tasks such as bridge examinations and station canopy repairs.

Method 3: A pre-planned and pre-documented reduced set of Test Before Touch actions.

This uses a risk-based approach to identifying a reduced set of Test Before Touch actions which are pre-planned, documented, and endorsed by two persons holding Nominated Person competence. This is most likely to be selected where the requirements of the other methods cannot be complied with, or are too demanding when considering the task and task delivery methods and the nature of the electrification network covered by the OLP. This could be, for example, a station with multiple platforms and lines and significant numbers of discrete in-line OLE features.

Method 4: A Test Before Touch action prior to every occasion where it is planned to touch a conductor.

This requires a Test Before Touch action to be carried out prior to every occasion where it is planned to touch a conductor. There is no requirement to pre-plan or pre-document the location of the Test Before Touch actions. This method is most likely to be selected in a post Emergency Switch Off scenario or other urgent situation where there is no ECP in the working party. It might also be used where the planned arrangements for methods 1-3 cannot be sustained.

The implementation of the new Test Before Touch standard has been supported by an impressive set of briefings, presentations, posters, videos, and social media posts; including a video to remind anyone how to use the standard if they have not had the need to use the process for some time.

Martin O’Conner, Network Rail technical head for contact systems said: “It is really important for everyone to remember that the Overhead Line Permit (OLP) is the point of reference for electrical safety for the COSS (OLP) and members of the working party. The Test before Touch actions process and form is an additional measure and control against inadvertent contact with energised live OLE, and no matter which Test Before Touch method is selected the COSS (OLP), or any other member of their working party, can request a Test Before Touch action.

“If there is ever any doubt when it comes to electrical safety, please ‘Choose to Challenge’ and raise your concerns. It may save your life or that of your colleague.” Changes to the Earthing Strategy for OHL are also planned by Network Rail, including the concept of Optimised Earthing based on local worksite earths. These changes are dependent on trials which are being undertaken on the Wales and Western Region to inform the next steps. Rail Engineer looks forward to reporting on these further measures once implemented, to further improve electrical safety when working on OLE.