Infraco Sub-Surface Ltd. - 2002/2003
In 2002/2003, we were commissioned by Infraco SSL to perform a detailed survey of underground stations and to recommend how this technology could be best employed in this difficult environment.
Between July and December 2002 Doug Edworthy, supported by members of the Comms Delivery Team, took measurements of magnetic noise in all public areas of the seven sample stations in 'traffic hours' (to ensure most electrical equipment would be in use). The noise measurements were followed during 'engineering hours' (at night, when the trains cease to run) with installations of temporary AFILS to assess the effects of building construction.
Doug Edworthy taking field-strength measurements at a trial AFILS installation
Recording measurements at a trial AFILS installation
The results of the surveys and tests were collated and analysed by D.G.Edworthy Associates and presented to members of Infraco SSL's Comms Delivery team, and representatives from Chief Engineer Directorate of LUL. The results made it clear that the full requirements for AFILS of the PPP contract could not be met in all areas, and that a pragmatic approach was required in order to provide hearing-aid users with a beneficial service. The results also provided technical justification for not installing AFILS in every public area.
The Chief Engineer felt that the results of the survey were so important that a further presentation was commissioned in order to give those responsible for setting LUL policy a wider appreciation of the technical limitations of AFILS in this environment. This presentation was held in April 2003 and was attended by representatives of LUL's Chief Engineer Directorate, Marketing and Planning, PPP Contracts, Kings Cross Redevelopment Project, Metronet-Rail SSL and also from Transport for London. Those attending judged the presentation to be of a very high standard, commenting "A very professional presentation. A valuable use of 1 1/2 hours." and "For the target audience it was excellent!".