The discovery of previously undetected amounts of asbestos has once again delayed the reopening of the Tyne Pedestrian and Cyclist Tunnels, originally due to be completed by August 2014. The tunnels, which connect Howdon and Jarrow, were closed in May 2013 following the initial discovery of asbestos and are now unlikely to re-open before summer 2017.

The Grade II-listed tunnels – the first ever to combine pedestrians and cyclists – were opened in 1951 during a period when Britain’s increased annual imports of asbestos had reached around 123,500 tons. Despite a growing asbestos awareness to the potential fatal health risks, use of the mineral fibres as a low-cost source of insulation and fire-proofing led to widespread industrial applications in building, construction, shipbuilding and manufacturing.

Problem was “worse than anticipated”

Renovation of the Tyne tunnels includes the replacement of two wooden-tread escalators, which were once among the longest in the world. Building contractors had begun removing asbestos from the lining in the escalator shafts and lower halls in May 2013 when they declared that the problem was “worse than anticipated” and expected that the tunnel would not be fully cleared of asbestos until February 2015.

However, the work continued to overrun when the contractor went into administration in March 2015, and a subsequent inspection of the tunnels led to the discovery of further asbestos. The principal engineers now expect the total removal or encapsulation of the remaining asbestos to begin in early 2016 and the tunnels finally re-opened in the summer of 2017 – three years after the original completion date.

Standard practice to house pipes below ground level

It is not uncommon for an initial discovery of asbestos to lead to further hidden quantities being uncovered. Cases are regularly reported where a very small amount or asbestos dust was detected in one area of a building, such as a stockroom, which led to further fibres being found in corridors, stairwells and most noticeably, in boiler rooms.

Public buildings, such as schools, hospitals and council offices are often connected by open or covered walkways and tunnels lined with hidden asbestos cement materials. It was often standard practice to also house pipes below ground level, which would run along the interior or exterior walls of service / pedestrian tunnels and walkways.

The professional construction industry estimate that any structure, particularly in the public sector, built or renovated up until the end of the twentieth century is liable to contain between 5 per cent and 30 per cent of asbestos-containing materials. Tunnels for pedestrian and cyclists are not the only structures which can present a potential risk.

Asbestos was present everywhere across the entire network

In May 2009, three years after construction on the central section of Crossrail tunnel network began, it was reported that asbestos was present everywhere across the entire London Underground network. Specific problem spots were said to be located at the eastern end of the Central line, running along the tunnel walls from Mile End station.

Plans to remove asbestos containing materials by the introduction of a train specially designed to remove dust were announced by Transport for London in 2014. But even after the asbestos has been removed or “encapsulated”, one third of the network could still be affected by an “asbestos, noise shelf and contaminated ballast”, which is mostly found on the Central, Jubilee and Northern Lines.

A survey ten years earlier into the likely health effects of Underground tunnel dust had concluded that levels were ‘highly unlikely’ to cause serious damage to human health and were below limits set by the Health and Safety Executive (HSE). However, air quality controllers have called for more up to date analysis.

Call for the total removal of all asbestos from the public domain

The existence of asbestos containing materials in constructions used in an endless number of applications continues more than thirty years after the first asbestos ban was introduced. The undoubted problems of potential exposure that the hazardous material can present at any stage in renovations or demolition underline the growing EU and international call for the total removal of all asbestos from the public domain over the next twenty years.

The All-Party Parliamentary Group on Occupational Safety and Health has also recently released a new report, which emphasises the need for a realistic timetable for the removal of asbestos from every single workplace in Britain by 2035.

The Health and Safety Executive (HSE) have reported at least 2,000 cases of mesothelioma are diagnosed every year in the UK and a further 45,000 deaths from the fatal asbestos-related cancer can be expected by 2050.