I'm hoping for some practical solutions to managing the control and PAT testing of extension leads in a construction setting. My concern is that tags will fall off the cables and it is impossible to differentiate one lead from another as they will all be identical. Therefore icould end up using cables which are outside of PAT test date. I was thinking different coloured leads for different time periods, but this would require purchasing at least twice as many leads as necessary. Are there any other suggestions?

It's the visual (whether formal or user check) that will catch the nicks, insulation damage, failed cable restraint etc. that a dumb machine won't. Frequency HSE suggest for construction environment is I recall quite stringent. Not being an electrician, I'm guessing it's important to ensure the earth continuity to a cable supplying a CTE transformer. For the cables on the output side, I'm not sure a PA Tester is going to tell you anything useful?

For leads then a visual inspection is vital (in particular on-site). Do this every time you use an unfamiliar lead and keep an eye on your own. An insulation test at 500v between poles (no live and neutral on 110v cte just 2-poles) and between poles and cpc. Continuity test on poles and cpc with ohm meter (same machine as insulation tester) A high reading will show either poor connections or that the copper conductors are failing within the cable. PAT machines will do this on a lead and far more when testing drills, washing machines etc.