The UK National and underground rail infrastructure is vital to the UK economy, writes Neil Foster of OPTEX

The Government plans to stimulate economic growth across Britain through projects such as the Elizabeth Line and HS2 which will add over 300 miles of track to our national rail network.

Every part of rail and underground infrastructure, whether it’s the station hall, concourse, roof, or platform of 2,500 stations, or the 20,000 miles of tracks with 30,000 bridges, viaducts and tunnels, and 6,000 level crossings, or the train depots and sidings, each element has its own individual security challenges to overcome.

Each aspect needs careful consideration and it’s a mammoth task, but new technologies are greasing the wheels of today’s network security and helping to keep passengers, members of the public, and rail workers safe.

Office of Rail and Road Safety figures for April 2021 to March 2022 show 11 passenger and public fatalities on stations, the London underground and tramlines.

On the main line, there were two workforce deaths and 15 members of the public who died trespassing or running the gauntlet on a level crossing. 

The UK does have one of the best safety records in Europe but how can new technologies help to drive down those numbers?

Detecting Safer Crossings

Network rail has closed over 1,250 level crossings in recent years. Yet the number of injuries and near misses has risen. In 2022, eight deaths were recorded (up from five in the previous year), and the number of pedestrians nearly hit by trains at level crossings reached the highest level in almost a decade. 

Level-crossing barriers can provide an obstacle for pedestrians or cyclists, who may struggle to navigate through the space with pushchairs or bicycles.

Some pedestrians though, appear less attentive, ignoring barriers, distracted by mobile phones, or taking pictures.

Cyclists, motorcyclists, and pedestrians also try dashing across as the barriers close only to get trapped in the wake of an oncoming train, like the 67-year-old BMW driver and his passenger in Hertfordshire last December. 

A signaller managed to raise the barrier to avoid a disaster. If a train collides with an obstacle such as a car or bike abandoned on a level crossing it can cause major disruption, delays and costs for rail companies.

OPTEX LiDAR

New advanced detection capabilities, such as OPTEX’s LiDAR sensors, can improve safety for level crossing users, operators, network rail and rail companies.

Any individual or object trapped between the barriers, or children fooling around on the crossing can be detected.

When the level crossing is active, it signals the LIDAR sensors, and the laser sensor scans the crossing.

If it’s clear, the signal turns green, and the train passes through safely. If not, the barriers are raised to let the vehicle or pedestrian leave the area before allowing the train to pass. If the vehicles stall or people are stranded on the tracks, the train driver can be warned, and the train automatically stopped until the obstruction is cleared. Network Rail has installed OPTEX’s REDSCAN LiDAR technology at more than 400 level-crossings from Scotland to the South Coast.

Dynamically Filtering Out Trespassers

Tunnels are another spot for trouble on the train tracks. Railway or subway tunnels are enclosed, dark, and often humid. Trespassing inside a tunnel increases the chances that a train will hit a pedestrian because they aren’t visible and are in a confined space with nowhere to escape. 

Accurately detecting a person entering such a dark and challenging environment is difficult enough, but it is even more complex when trains are using the tunnels at the same time. New innovative laser sensors are not affected by humidity or lighting conditions. 

Equipped with intelligent sensing analytics, the technology auto-learns changes of the environment to adapt to these conditions and to alert the system if its ability to detect is affected, for instance, due to a soiled lens.

Advanced intelligent detection sensors, such as REDSCAN Pro, are equipped with dynamic event filtering.

The system can monitor a tunnel entrance and raise the alarm based on the size of object detected or the sequence at two separate predetermined zones; the first zone is across the tunnel up to human height or 2m, and the second higher zone above human height or 2m.

When an object is detected entering the tunnel in the first zone at the first height, the system is primed; it takes a second reading milliseconds later. If the second reading is in the second zone at a greater height, the system stands down – it’s a train.

The first reading was just the bull nose; the second is the body of the train. If the second reading is void or is again in zone one at human height, it is a person (or possibly a deer), and both the control centre and train driver are alerted, so the train can be slowed or stopped to avoid an accident.

Trespassing inside a railway tunnel or along the train tracks takes a significant toll on the railways.  Network Rail spent £2 million last year removing graffiti from infrastructure sites across the country. In the southeast alone, 450 locations had to be cleaned up.

Over a thousand trespassing incidents were recorded last year, causing 50,000 train delays at a cost of £3.5m.

The authorities are using drones fitted with thermal imaging cameras and high-quality zoom capability to find trespassers to reduce delays and the potential injury or death. 

Depots need security to lessen the risk of trespassers and trains stabled there or in sidings are at risk from graffiti or arson. 

Depots contain valuable equipment making them prime targets for theft and criminal activity. They’re often large which makes location of intruders a real challenge. The sooner an intruder is located, the faster the situation can be dealt with.

Narrowing down an intrusion area is mainly achieved by creating detection zones that work with camera pre-sets to help security teams confirm and track possible trespassers.

Pinpoint Accuracy

At large valuable sites, and particularly in large perimeters, point detection technologies can enable a faster and more precise detection of intruders, guiding cameras to focus on the right location or area.