According to the Swiss Association of Public Transport, there is nowhere in the world where the rail network is so intensively used as Switzerland. At an average of 93 trains per day per kilometre of track there’s no doubt that this is probably the case.  However as train travel continues to increase in the UK, some might argue that some of our main routes are close to capacity and not far behind in terms of train density.

With high train density comes the challenge of maintaining the track and gaining safe access without disrupting trains. It might be no surprise then that ATWS is widely used in Switzerland. Automatic Track Warning Systems (ATWS) use train detection devices fixed to the track and deliver a warning to workers through a series of lights and sounders.  Providing track access to maintenance personnel, there can be as many as 100 ATWS systems in use at the same time on the Swiss rail network.

With a rail network 10 times the size of the Swiss, one might expect there to be similar numbers in use in the UK, however it’s likely that less than 5 ATWS systems are operating at the same time in this country. So why isn’t ATWS more widely used in the UK?

 ‘It’s a lot to do with a perception that ATWS is expensive and an inconsistent implementation of RiMini’ commented Chris Foreman, General Manager of Schweizer Electronic Ltd, ‘although ATWS is taught as part of Personal Track Safety (PTS), there’s not enough understanding of what it does and its cost benefits compared to traditional forms of track worker protection’.

The high cost of line blockages compared to using an ATWS

The cost savings of ATWS can be dramatic when you compare the true cost of using ATWS compared to blocking a line outside a white period. White periods are specific times during the week when no trains are scheduled, and track is available for maintenance work. It is widely reported that if Network Rail blocks a line for maintenance work during a scheduled train service it pays fines to the train operating companies for delays or cancellations. These potential costs however rarely seem to be taken into account when comparing the costs of using ATWS as an alternative.

Short and unreliable possessions reduce productivity

Carrying out maintenance work on the busiest lines under possession is likely to get more difficult as steps taken to implement a 7 day railway continue, particularly when you consider that an extended timetable means more trains with correspondingly more maintenance work, but shorter possession availability to achieve it.  ‘Some delivery units already experience short and unreliable line blockages which impacts on productivity’ said Chris Foreman ‘in addition some contractors have told us that although they pay their track workers for a full shift, they may only get a few hours of productive time on the track. What’s frustrating is that the contractor can see the benefits of using an ATWS system but hasn’t the motivation to use it when the network are happy to pay for the cost inefficiencies’.

A lookout is likely to make a mistake every 1000 actions

Perhaps more concerning than the wasted productivity opportunities, are instances where ATWS has not been fully evaluated as an option before reverting to lookouts. With more stringent legislation, you might expect delivery units to be more conscious of proving that appropriate steps have been taken to minimise risks. ‘ATWS providers still come across instances where ATWS could have provided a cost effective form of work protection, taking less than 25% of the total project time to install it ’, continued Chris Foreman ‘but for whatever reason an ATWS system was not even considered. An ATWS system rated at SIL3 (Safety Integrity Level 3) only theoretically fails once every 10,000 years, or practically never, whereas a lookout rated at SIL0 is likely to make a mistake every 1000 actions’.

With such compelling reasons to use it, how can ATWS providers help the rail industry increase the usage of ATWS and benefit from its safety and productivity improvements? ‘It’s probably just as simple as giving an ATWS provider a chance to quote’ claimed Chris Foreman ‘we believe that most delivery units that trial ATWS will not want to revert back to the traditional ways of warning track workers. At the moment, most use of ATWS in the UK is concentrated to localised areas of the rail network that tried it and now adopt it for much of their works. With CP5 and future rail maintenance budgets under continued pressure, ATWS could help make significant savings, while maintaining high levels of safety’.

With increasing passenger numbers and capacity constraints on the UK’s main routes, some renewals and enhancement projects are suffering with lack of sufficient track access to carry out work activities. Whilst running a Seven Day railway benefits both rail passengers and freight operators, the challenge for the rail industry is a difficult one. More trains, means more maintenance, which in turn means more pressure for line blockages, which disrupts train services itself.

This ‘Catch-22’ situation is felt most by the rail construction and delivery units who can struggle to get a possession on some of the main routes. ‘We are seeing increasing numbers of clients with this type of problem’ says Chris Foreman, General Manager of Schweizer Electronic UK. ‘Clients are under increasing pressure to bring jobs in on budget, but are finding it very difficult when access is limited on complex track. Access arrangements can have a major impact on the cost of delivery’.

Where access is granted, there can be other problems in that short and unreliable possessions impact on productivity. Contractors might get a short possession but still have to pay their track workers for a full shift, even if they only get a few hours of productive time on the track. What’s more, with increased pressure to hand back possessions on time; this access can sometimes be cut short in order to accommodate train services. 

What’s the answer for track access?

Approved by Network Rail, a possible solution is Automatic Track Warning Systems (ATWS). These systems use train detection devices to warn workers and machinery of approaching trains through a series of lights and horns. It’s possible to set up an ATWS on a complex layout within a relatively short space of time. Since track workers are only interrupted by train movements and warnings, ATWS can provide more productive time on the track.

Although regulations regarding Adjacent Open Line (AOL) working have become more stringent recently, there are still suitable sites where ATWS system together with a fence can allow heavy machinery to continue to work next to an AOL. This means that a route can be kept open, avoiding excessive fines on the busiest routes.

Determining worksite suitability for ATWS

‘You’d be surprised how many sites are suitable for ATWS’ says Chris Foreman, ‘giving Schweizer or one of our approved partners a call is the first step to determining suitability. Generally we can tell quite quickly if it’s possible to carry out activities with an ATWS’. As a Safe System of Work, ATWS sites are planned, installed and operated by competent personal.

With most use of ATWS currently concentrated to a few areas of the UK rail network, and with track access and rail maintenance budgets under continued pressure, ATWS could provide the solution that rail construction and delivery units are seeking in order to create safe access, while making significant savings in productivity and reducing passenger disruption.

Schweizer Electronic provides automated warning systems specifically for protecting people and equipment on running rail. Formed in Switzerland in 1964, Schweizer’s core technology is its MINIMEL95 system, a combination of rail-based sensors, a central data processor and a series of warning devices, which offer highly reliable automated protection to work sites.