There are quite a lot of companies in the UK who provide CAT and Genny training, and it can be called by different names, such as HSG47 training, EUSR CAT and Genny training, and so on, but all are basically teaching the use of the Cable Avoidance Tool (CAT) in combination with the Signal Generator (Genny). The reason for the different names is that it will depend on which authority the training company is recognised by. So if the company is recognised by the Energy and Utility Skills Register it will probably call its' training EUSR training and those passing its' course would be awarded an EUSR card to show that they had done so. Another company would refer to HSG47 which is the publication by the Health and Safety Executive which sets standards for safety in excavation.
Despite all the available training, the sad fact is that there are approximately 60,000 utility strikes every year in the UK – around 230 every working day – and they can result in serious injuries which are sometimes fatal, so there is a long way to go yet. This can be attributed partly to the fact that the CAT and Genny, although clever instruments, do have some limitations, so a surveyor could be fooled into thinking there is no utility where he is about to excavate even though there might be.
A very simple example of that is the use of the CAT on its' own, which in Power Mode can only locate electricity cables with power running through them. So if you were out in the street at night and the street lamps were on, it should locate them. If you went out next morning when the lamps were off it would most probably indicate that there is nothing there. This does depend on the type of street light installed, but you can see the point. This is one of the reasons why the CAT should always be used in conjunction with a Genny: if you know for certain that there are only electricity cables that are live where you are going to dig, then it could be argued that the CAT alone is sufficient. The trouble is that you don't. You might even find a live cable, but you won't know that there is a gas pipe running alongside it just a couple of feet away, and this could be where you decided to dig because you know where the electric cable is.
When used in conjunction with the Genny, the CAT can locate other services such as metal water pipes, plastic or clay pipes, telecoms and so on. You may also need to add some other things such as clamps, flexible drain rods, and a sonde. A sonde is a small piece of equipment that you attach to flexible drain rods if you need to locate, say, a blockage. It sends out a signal which the CAT can detect when it reaches it so that you know where the blockage is.
Of course, it is one thing to know where a utility cable or pipe lies, but you may also want to know how deep down it is. If you are only going to be digging down a couple of feet and you can find that the service is six feet down, then you can probably proceed with a little more confidence, albeit carefully. Some of the better equipment available today like the CAT 4 can also indicate the depth of a service, so you could find that a service is only just below the surface which would mean that you would have to change plan accordingly.
Once you fully understand how to use them, the majority of CATs and Gennys are simple enough to use, but note the words "fully understand". This is why it is really essential for operatives to take a CAT course, particularly in the case of the more advanced models which have additional functions such as CATs with the ability to store scan data and even show the path that an operative has taken. It is also worth noting that some services such as local authorities, Network Rail, and so on, will not allow operatives on site unless they have the appropriate certification.