Objetivo Traditionally underground communications have employed a dedicated cable medium. However in emergency incidents these systems are susceptible to damage, particularly from falls of ground. Damage to the cable can result in loss of communication and this is particularly onerous where miners are trapped behind falls in single entry situations. Such an incident has recently been recorded at High Moor Colliery where contact was lost in exactly the aforementioned circumstances. Here a high integrity means of communication would have been of significant value. The trend towards increased use of retreat working and the adoption of single entry production faces reinforces the potential benefits of such a system,. The aim of this project is to develop and fully qualify the suitability of a communication system for both mines rescue use and normal day-to-day communications requirements.Previous studies infer that in order to provide reliable voice communications over long distances and, in particular, through falls of ground, low or medium frequency (< 2 MHz) inductively coupled radio provides the best option. Guided medium frequency (MF) communication systems employing the inductive radio principle have been widely used outside the UK. These systems generally require dedicated guide conductors. For rescue purposes it would be necessary to rely upon the existing mine wiring and metallic infrastructure since these are more likely to remain substantially intact after an incident. Being able to use existing cables additionally confers flexibility in normal use.The uniqueness of MF communications is that a galvanically continuous assembly of wiring is not required. There exists a local coupling between cables and other conductors. An induced signal on one type of conductor will parasitically couple to all others even if breaks or earth terminations exist in the ensemble. Furthermore, MF electromagnetic waves have been shown to be capable of propagating useful distance within a conductor-free coal seam. In general propagation occurs via either a coal seam waveguide mode or electromagnetic coupling into and out of mine wiring, or both; this is thought to offer potentially side coverage and high integrity.The programme of work will be split between equipment development and underground evaluation. The major activities will encompass:i) undertaking an update survey of developments in other communication technologies to confirm whether MF inductive communications remains the optimum technology (eg low bandwidth, long distance communication is possible with ELF/VLF); ii) development and engineering of either a medium frequency communication set or any viable alternative identified (i) above. Here, existing proprietary equipment or developments will be assessed for their suitability;iii) examination and development of high efficiency aerials and couplers;iv) assessment of propagation involving several sites with differing conductor arrangements, conductor free zones, and through simulated falls of ground;v) qualification of the system performance expected in any arbitrary site;vi) assessment of networked communications and alternative applications such as shaft communications and low speed data telemetry. Programa(s) ECSC-WORKSAFE C - First joint research programme (ECSC) "Safety in the European Coal and Steel Community industries", 1989-1993 Tema(s) 2.4 - Monitoring, telemetry, data presentation, remote control, automation and communication Convocatoria de propuestas Data not available Régimen de financiación Data not available Coordinador British Coal plc Aportación de la UE Sin datos Dirección Eastwood Hall NG16 3EB Eastwood Reino Unido Ver en el mapa Coste total Sin datos
