Pipeline Inspection

In the early eighties and speaking generally, the only internal pipeline inspection was either carried out by the sewer inspection companies, who would be inspecting primarily dry sewer pipe（Underground Sewer Pipe） sections more than short distances; normally not exceeding 150m and who would quit if the pipe became surcharged for the point exactly where the camera would turn into submerged along with the oil market assistance firms who would run 'intelligent pigs' though the oil pipes to assess weld integrity, pipe wall thickness and situation in order to assess pipeline longevity and protected operating pressure.

At this time the water businesses who were largely oblivious towards the internal condition of their pipelines, adits, aqueducts and tunnels were beginning to possess concerns about the integrity of their assets, a lot of of which had been constructed during the Victorian era or much more not too long ago in the early fifties and had never ever been inspected and have been unsuccessfully trying to locate companies and/or equipment that could carry out such surveys.

In some cases they had been in a position 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 certainly fraught with possible dangers, not least of which incorporated the danger of collapse, flooding along with the accumulation of toxic gasses.

De-watering came with its personal set of possible risks to the structural integrity in the concrete, tunnelled and brick constructed pipelines; in numerous instances, little leaks designed by displaced joints, erosion and localised harm etc. enabled the leaking water to find a path by means of the ground and over a number of years, earth could be washed out from about the pipe, usually resulting in massive water filled voids forming about the outdoors on the pipeline.

The newly de-watered pipeline which would often be partially reliant around the head of water within the pipeline (trying to push the walls out), to preserve its structural integrity, could all of a sudden be subjected to a number of tons of water outdoors of the pipeline (wanting to push the walls in), creating localised areas of external high pressure, which would usually bring about pipe failure and localised collapse, causing subsidence from the ground above the pipeline manifesting as holes within 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.

Within a very quick time frame the HSE Diving Executive, showed a keen interest within the safety aspect of sticking divers up pipes and before long an excursion array of about 30m as a maximum was considered secure, offering that each of the needed security precautions had been in spot.