HomeSPONSORED FEATUREReducing risks in depots

Reducing risks in depots

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At the end of this month, industry regulator, the Office of Rail and Road (ORR), will publish its final thoughts on how Network Rail should allocate its budget over the next five years, during Control Period 6.

June’s draft determination focused heavily on worker protection, advising an extra £80 million should be spent on installing additional safety measures, from a recommended total renewals budget of £18 billion.

This was followed swiftly in July by the ORR’s annual health and safety report, which revealed “continuing significant failures, particularly in regards to exposure to OLE and third rail” are still occurring on our railways.

So, the gauntlet has been thrown down. How does the industry reduce the risk of serious injuries, or on occasions, worse? Despite recent upgrades, the majority of the existing rail network is ageing. What can be done, practically and cost-effectively, without ripping it up and starting again?

Britain’s railways remain the safest in Europe, but high voltage equipment, heavy machinery and moving vehicles make maintenance depots, in particular, potentially risky places to work. When coupled with an inconsistent approach to staff safety, and some facilities still relying on poor, ad hoc risk control arrangements, it is undeniable that more can be done.

The ORR has noted this year that technological developments offer great opportunities to improve safety, yet it believes such innovations should be introduced in a way that takes account of human interaction.

This philosophy is at the core of Zonegreen’s working practices and the Sheffield-based depot safety specialist continues to develop highly sophisticated systems that protect personnel, without impeding depot operations or productivity.

Protection via prevention

Perhaps best known for its market leading Depot Personnel Protection System (DPPS™), which is installed extensively across the UK, Australasia and the Middle East, Zonegreen is also a leading expert in interlocking, combining intuitive functionality with easy to use controls to improve worker safety.

The firm provides advanced interlocking systems for new build and existing facilities that prevent personnel and equipment entering dangerous areas and coming into contact with live third rails or overhead lines.

It has developed a safe system of work that absolutely prevents access to high level platforms by means of a fully guarded stairway and interlocked gate, which can only be opened with a key that is released from a control panel when the OLE is isolated. The sequence of unlocking and removing keys, which in turn allows other keys to be released, ensures prohibition of access to areas unless they are safely isolated and earthed. It is also possible to monitor the position of the gate locks to ensure that they are all closed and locked prior to enabling the reenergisation of the OLE.

In addition, a series of green lights can be provided that illuminate when roads are isolated, earthed and interlocked, providing a visual indication that it is safe to work.

Interlocking is far superior to ‘permit to work’ systems that rely entirely on everyone operating within the area of risk to follow procedure continually. One lapse of concentration is all it takes to place a member of staff in danger, so taking away the margin for human error can, potentially, save lives.

Further refinements can be included within an interlocked OLE system to protect third party depot equipment. For example, to eliminate hazards from trains with two pantographs or multiple pick up shoes and to ensure the safe placing and removal of earth loops. In the past, failure to remove earth loops has caused numerous incidents, subsequent injury to workers and damage to equipment.

Depot installations that have the potential to come into contact with a live OLE, such as cranes, pressure washers and mobile gantries, can also be interlocked to prohibit their operation in potentially unsafe conditions.

Staff working on high-level access gantries are not only exposed to the dangers of OLE, but are also at risk of falls from height. A relatively new innovation in the improvement of depot safety is GapSafe – an inflatable bladder that closes the space between a maintenance platform and train. It prevents personnel, tools and equipment from dropping between the train and the maintenance platform, eliminating injury to workers and damage to plant and equipment.

Unlike traditional fall arrest systems or fall prevention flaps, GapSafe fills spaces of varying sizes quickly, without causing damage to the train or maintenance platform. Interfacing Zonegreen’s interlocking technology with the bladders allows them to inflate automatically when the first gantry gate is unlocked. This ensures that staff are in a position of safety whilst setting up a safe system of work, eliminates human error and protects personnel working at height. When the OLE is isolated, the gantry gates are unlocked and GapSafe is in place, the aforementioned green beacons illuminate above the respective road to indicate it is completely safe to enter.

Christian Fletcher, Zonegreen’s technical director, said: “Our interlocking is so flexible it can be adapted to all sorts of third-party depot equipment. The interface with the GapSafe bladders is the perfect example of how advanced technologies can be used together to provide a fully integrated, fully automated safety system.”

Third rail risks

The prevalence of third rail electrification in the South East is greater than in any other area of the country. In this day and age, the concept that bare, 750V live conductors run through our places of work at ground level is hard to comprehend, yet these are exactly the dangers facing depot operatives in this region on a daily basis.

Traditional safety measures, for example, the use of protection boards and written procedures, are still commonplace. However, these manual systems are open to human error and can lead to fatalities, resulting in untold grief for family and colleagues and huge fines for employers.

Zonegreen is leading a two-pronged attack on the risks associated with third rail, via its interlocking and Points Converter systems.

Interlocking is applied in much the same way as it is to OLE equipment, but at low level. Areas of risk are fenced off and access is controlled via secure gates, which cannot be opened until the third rail has been isolated.

This type of system is particularly beneficial on stabling roads, where operations such as cleaning and sanding are completed. Workers are often required to access the six-foot space alongside the third rail, putting them at considerable risk.

Points Converter is an innovative method of automating manual points that has been designed to increase safety in rail depots and can be used to reduce the dangers associated with the third rail. Fitted retrospectively to existing manual hand points, they can be controlled either by key switches located in a position of safety, by remote handsets or by a central computer system. This allows the point to be operated remotely, without putting people in harm’s way.

Using Points Converter removes the need for shunters to traverse potentially long distances to reach manual points, at all times of the day and night. In areas where there could be poor lighting, ballast and uneven surfaces, the dangers of contact with the third rail are heightened and ever present.

It is a low-cost, easy to use system that maintains the integrity of the underlying hand point and requires only minimal civil works and changes to operating procedures. Routes can be pre-set through multiple points that can be reconfigured or upgraded at any time, and it incorporates an event logging facility that enables the depot manager to keep a record of all points operations.

The future

Whilst many UK depots, particularly those associated with the Thameslink, IEP and Crossrail projects, already benefit from Zonegreen’s technology, there is still room for improvement, as indicated by the ORR’s health and safety report.

Clearly the human grief and suffering caused by workplace fatalities is unquantifiable, but it is also difficult to obtain precise estimates of the financial costs. When legal proceedings, medical charges, damage to equipment, loss of production and insurance are taken into account, a figure of anywhere between £2 and £7 million is not unreasonable. This would be crippling for all but a few large organisations, so it is vital everything possible must be done to reduce worker risk.

Christian Fletcher added: “The safest way to protect personnel is to keep them out of dangerous areas. It is vital, therefore, to have properly engineered systems that can not only play a major role in staff safety, but also have the ability to improve efficiency. By applying its expertise, experience and adaptable technology to the issue, Zonegreen is helping to prevent personal injury and the associated costly damages.

“At the moment, the rail industry still has an inconsistent approach to keeping workers safe. Until the failings of manual systems are addressed across all rail depots, the potential for loss of life remains all too real. Our user-friendly DPPS™ can be developed to encompass both electronic and mechanical interlocking, providing proven protection against the risks identified.”

Read more: Depot control for the 21st century


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