Almost every crew working near buried services carries a detection kit, and that is a good start. It is not the finish. The crews that reliably avoid cables are the ones trained to use that kit in the right order, and on a live power cable the difference is the whole job.
Walk onto any utility or construction site in the country, and you will find a Cable Avoidance Tool in nearly every van. That is a good thing. The equipment is standard, widely owned and trusted, and it works. What it cannot do on its own is make the decisions: owning a locator and knowing how to get the most out of it are two stages of the same job, and underground strikes remain common precisely because the second stage is the one that gets skipped. The Health and Safety Executive records hundreds of strikes a year, and the real figure, counting unreported near misses, is higher. The good news is that this is a solvable, trainable problem.
It is worth being plain about the stakes, because they are what make the training worth it. Catch a live 11kV cable with a bucket or a hand tool and the result is an arc flash capable of causing serious burns or worse. Most strikes end in damage rather than injury, which is the trap: the near miss becomes routine, the risk fades into the background, and the one that does cause harm arrives without warning. A trained crew is what keeps that risk in view and keeps the tool earning its place.
That is exactly what proper EUSR Cat 1 training delivers, and it is the work Sygma Solutions has built its name on. The Wigan firm, the only independent specialist of its kind in the UK, has spent over twenty years turning capable kit into reliable results on site. Founder Peter Ashcroft puts the positive case simply. “The locator in the van is a good tool, and in trained hands it is a brilliant one,” he says. “What we do is give operatives the method to go with it, so a quiet reading gets confirmed rather than assumed. Train that habit in and strikes stop being a matter of luck.”
What a passive sweep misses
The weakness sits in how the kit is usually handled. A Cable Avoidance Tool in its passive modes only detects services that happen to be giving off a signal. Plenty give off nothing useful: an unenergised cable, a circuit switched off at the time, a balanced three-phase load that cancels its own field, a short metallic run with nothing re-radiating along it. Any of these can sit directly beneath a confident sweep and register as clear ground. For a safety-critical task, relying on what happens to be detectable in passing is a thin basis for putting a tool in the ground.
Genny and CAT, in that order
The fix Sygma trains is a change of habit rather than a change of kit. The signal generator, the Genny, applies a known signal to a target so it can be traced deliberately, turning a guess into a confirmed location. The method the firm teaches is Genny and CAT, in that order: connect the generator first, confirm the services you expect, and work outward from certainty rather than assumption. It is a small reordering of the routine with a large effect on what the survey actually finds. The shift is one Sygma’s clients report after training, with Genny use on live sites rising from below 30% to between 70 and 80%, against a target of better than 60% on every survey. Crews from Severn Trent Water and Wales & West Utilities are among those trained to it.
Competence, not just kit
None of this is optional in spirit. HSG47 and the CDM Regulations 2015 both place a duty on those planning and carrying out excavation to locate services before breaking ground, and locating them reliably is a trained skill, not a function of owning the hardware. For anyone responsible for safety on site, the question is not whether the crew has a CAT scanner. It is whether they have been trained to use it in a way that would catch the cable the passive sweep misses.
The strike that never happens leaves no mark, generates no report and earns no thanks, which is exactly why the training behind it is easy to overlook. On a live site, the difference between a clear reading and a confirmed one is the difference between a routine dig and a serious incident. The kit on its own cannot tell them apart. The person holding it, trained properly, can.
The post Why a site full of CAT scanners still strikes cables appeared first on HSE Network.