Hazard Complexity of rail infrastructure
Knowledge and understanding
|Complexity of rail infrastructure||
Understand all associated hazard knowledge
The hazards of attending rail-related incidents may be amplified by the complexity of the rail infrastructure. Fire and rescue services may have to access, bypass or deal with elements including:
- Large rail terminals and stations
- Depots or sidings
- Complex rail layouts or junctions, which may have:
- Rail lines that are used by more than one rail system
- Rail vehicles rapidly moving from one track to another
- Bidirectional rail vehicle movements
- Security features, such as fences and locked gates
- Level crossings
- Railway arches, bridges and viaducts
- The features of the operational railway, the area between the boundary fences, which comprises:
- The track – rails, points, fasteners, sleepers, ballast and subgrade
- Lineside structures including fences
- Power systems, including overhead line equipment (OLE) and conductor rail equipment (CRE)
There may be adjoining properties that may become involved in an emerging incident and neighbouring properties that may need to be considered for evacuation purposes. Larger train stations may have phased evacuation, depending on the nature of the incident or the means of alarm initiation. It is vitally important for personnel to fully understand the infrastructure risks and the principles of evacuation. See National Operational Guidance: Operations.
A station usually consists of one or more buildings for passengers, and possibly goods, and may be constructed over a number of levels. A 'terminal' or 'terminus' is a station at the end of a railway line.
Large train stations may have a number of rail companies operating in different areas, with varying emergency procedures. Railway stations will have public and non-public areas; the areas for providing public access will generally present limited hazards. Some facilities provided to keep the public safe can present a potential obstruction to a fire and rescue service, for example, platform edge doors or barriers. Methods of opening these facilities should be readily available to station staff.
Non-public areas can present additional hazards to those generally encountered in public areas, such as:
- Fast-moving rail traffic
- High voltage electrical equipment for train stations and infrastructure
- Power supply equipment
- Unusual direct access to the track
In addition to the hazards encountered on other parts of the railway, firefighters and station staff should also be aware of other factors that may have a bearing on incidents located on, or near, a railway station. Many railway premises are historic buildings and are likely to have heritage value.
Depots or sidings
Depots or sidings are short stretches of track that are connected to the main infrastructure. They may be provided for a number of purposes, such as:
- Parking or storing rail vehicles
- Loading and unloading
- Allowing rail vehicles to pass
- Storing of track welding powder
- Storing of detonators, which are used as warnings signals
Additional hazards that may be found in depots or sidings include:
- Rail vehicles may be located close to each other
- There may not be signals in use
- Goods on board rail vehicles may include hazardous materials
- It may be difficult to identify the responsible person as their control and ownership may be shared between several parties
Level crossings are railway lines crossed by a road or right of way, usually for road vehicles and pedestrians. Crossings are categorised into two main types:
- Active crossings, which give road vehicle users and pedestrians warning of a rail vehicle approaching with the use of gates, barriers, warning lights or alarms
- Passive crossings, which do not have a warning system for approaching rail vehicles; road vehicle users or pedestrians are responsible for checking that they can cross safely
Incidents involving level crossings include road vehicles or pedestrians being struck by rail vehicles.
For further information about level crossings, including information about each of the crossings in Great Britain, see the Network Rail website, Level crossing safety
Railway lines that run though major towns or cities are frequently elevated, with railway arches constructed beneath them. Railway arches are often adapted for uses, such as garages, storage, entertainment venues, offices and workshops.
Incidents in railway arches may impact on the rail infrastructure above; for example if they are involved in fire, the smoke may affect the movement of rail vehicles and the overhead line equipment (OLE).
Bridges and viaducts
There are a number of additional hazards to consider when dealing with rail-related incidents in the vicinity of bridges or viaducts, such as working at height, restricted safety areas and difficult access.
Access to rail-related incidents may be via the track side, which can include embankments or steep slopes. The track side may contain:
- Redundant railway material, such as sleepers, rails and clips
- Undergrowth, such as leaves, scrub and brambles
- Waste from fly tipping
These may present amplified slip, trip, fall and fire hazards. They may also hinder the access of personnel trying to reach the incident.
The track side may be damaged if there are large volumes of water, for example from flooding, fire water run-off or high volume pumping. This can result in weakened embankments or misaligned running rails.
A set of railway points is a mechanical installation enabling rail vehicles to be guided from one track to another. Points can be either mechanically or electrically moved from within a signal box or a control room and may be remotely operated.Even if traction power has been isolated, points can still move as they are powered by a separate electrical system and may still be operated from non-electric or diesel traction rail vehicles.
The operation of points can happen quickly and without warning; this could result in foot entrapment or injuries, with an increased risk of exposure to moving rail vehicles.
A single signalling centre can control many miles of track, and may be unaware of the presence of personnel near the points.
To avoid railway points becoming frozen and inoperable during cold weather, point heaters that are used. These are predominantly electrical, but older heaters use liquefied petroleum gas (LPG). The LPG cylinders would be housed in small wooden cabinets next to the track and the main heating assembly would be supplied with gas via a length of low pressure tubing. This arrangement may still be found on heritage or industrial railways.
In addition to the hazards associated with contemporary railways, heritage railways may have additional physical hazards including:
- Point operating rods which run adjacent to the tracks in the drainage cess and cross the tracks underneath the running rails.
- Semaphore signal operating wires, pulleys and rods which run adjacent to the track in the drainage cess on raised supports, and crossing the tracks underneath the running rails.