Pipeline Inspection

Within the early eighties and speaking normally, the only internal pipeline inspection was either carried out by the sewer inspection businesses, who will be inspecting primarily dry sewer pipe（Underground Sewer Pipe） sections over quick distances; normally not exceeding 150m and who would cease in the event the pipe became surcharged to the point exactly where the camera would grow to be submerged and also the oil sector help companies who would run 'intelligent pigs' even though the oil pipes to assess weld integrity, pipe wall thickness and condition in an effort to assess pipeline longevity and secure operating pressure.

At this time the water organizations who were largely oblivious towards the internal condition of their pipelines, adits, aqueducts and tunnels were starting to possess concerns in regards to the integrity of their assets, numerous of which had been constructed in the course of the Victorian era or more recently in the early fifties and had by no means been inspected and were unsuccessfully trying to find firms and/or gear that could carry out such surveys.

In some circumstances they have been able to de-water the pipelines（Water Supply Pipes） and if large adequate diameter, they would send a confined space group in to carry out a visual survey; such surveys had been clearly fraught with potential dangers, not least of which included the danger of collapse, flooding along with the accumulation of toxic gasses.

De-watering came with its personal set of potential risks towards the structural integrity on the concrete, tunnelled and brick constructed pipelines; in numerous situations, little leaks designed by displaced joints, erosion and localised harm etc. enabled the leaking water to discover a path through the ground and over quite a few years, earth will be washed out from around the pipe, typically resulting in big water filled voids forming about the outdoors in the pipeline.

The newly de-watered pipeline which would often be partially reliant on the head of water inside the pipeline (looking to push the walls out), to maintain its structural integrity, could abruptly be subjected to numerous tons of water outside from the pipeline (wanting to push the walls in), producing localised regions of external high pressure, which would typically cause pipe failure and localised collapse, causing subsidence of the ground above the pipeline manifesting as holes inside the ground that would seem 'over-night'.

At around this time there was an escalating demand in the Water Companies to send divers up water filled pipes（Tap Water Pipe） armed with CCTV cameras, to survey for as far as their nerve or umbilical length would permit.

Inside a very short time period the HSE Diving Executive, showed a keen interest in the safety aspect of sticking divers up pipes and ahead of long an excursion selection of about 30m as a maximum was regarded as protected, providing that all of the needed security precautions have been in place.