St Pancras International is a key London interchange and the very definition of a ‘destination station’. Managed by Network Rail High Speed Ltd this buzzing regional, national and international travel hub has been part of Britain's railway heritage for the better part of 150 years.
St Pancras International is a key London interchange and the very definition of a ‘destination station’. Managed by Network Rail High Speed Ltd this buzzing regional, national and international travel hub has been part of Britain's railway heritage for the better part of 150 years.
Designed by William Barlow in 1863, it gained instant fame for its “Barlow Shed” train shed arch that spans 73 metres and is over 30 metres high at its apex; at the time, the largest enclosed space in the world. The Grade 1 listed red brick Gothic landmark façade fronting the station was the result of an architectural competition in 1865 and became the Midland Grand Hotel. In 1935, the hotel was closed and the building became railway offices, renamed as the St Pancras Chambers. .
Following a site safety upgrade, the Eurostar terminus at St Pancras International in London bristles with the latest high-performance fire detection and alarm technology, including no fewer than 5,000 Hochiki ESP – Enhanced System Protocol – analogue addressable devices, installed throughout the site. A variety of Hochiki devices were selected, each chosen for its proven ability to combat fire risks in the huge multi-activity station. They included optical smoke sensors for back office and main passenger concourse areas; multi-sensors for more challenging environments such as plant rooms and workshops; heat detectors in kitchens and toilets; audio visual devices and base sounder beacons.
They are all automatically re-calibrated every 24 hours to compensate for any environmental contamination and to ensure that they continue to operate reliably at the specified sensitivity. Indeed, a key factor cited by the installer for the decision to opt for the Hochiki solution was the flexibility of the devices to be compatible with other products already installed. For example, Hochiki's ESP protocol devices are configured to share system information and event details on a highly fault-tolerant secure network.
With huge numbers of people converging on the station's platforms at peak travel times and the travelling public's ever-present concerns regarding terrorist activities, ensuring the minimum disruption from false alarms was a paramount consideration. In the event of a confirmed fire, the system directly controls and monitors the station's voice evacuation system, which is audible in all the station's public areas. However, in places where high levels of ambient noise may make it difficult to hear voice alarms, such as toilets, Hochiki beacons were also fitted.
Famous for helping to reduce false alarms, Hochiki's ESP protocol uses a combination of sophisticated algorithms that reduce data corruption. Additionally, with parity and checksum error detection principles applied to every set of data, unwanted external “noise”, such as EMC interference is eliminated.
Hochiki optical smoke sensors are designed for both efficient detection and the virtual elimination of false alarms. The sensor's chamber incorporates uniquely angled baffles which allow air and smoke to circulate within the chamber but reduce the ambient light entering the chamber, thus improving the response of the optical elements. The sophistication of the sensing elements in the chamber enables it to also sense a wider range of fire types, so providing a more balanced response to different types of smoke particles. This is a Hochiki-developed technology that the company calls its “high-performance chamber”.
The main control panel was designed and engineered to meet High Speed 1 requirements. It incorporated 196 fire zone indicators and several firefighters' control switches to allow the plant to be managed anywhere in the network via Hochiki loop output relays. A repeater panel, with an emergency fire telephone, was incorporated into the system for use by the fire brigade should an emergency condition occur within the main control suite.
