On Tue, 10 Mar 2015 10:21:26 -0700 (PDT), wrote:

There is an issue but I think its being exaggerated. Using meters on 5-32A fused/mcb circuits is a very different ballgame to exploding them with 25,000A. Its when you're probing about inside a live CU that you really need that CAT certification. Most diyers are never going to do that.

I disagree, a DIY'er could do exactly that.

Cheapo meters are fecking lethal anywhere near mains, ****ty design, glass
fuses, no blast shields, faked certification, crap probes. The non professional
user won't even begin to understand that there could be a problem. The properly
designed led testers and volts sticks are far safer than cheap and patently
uncertifiable 'universal' test meters.

http://ecmweb.com/arc-flash/case-deadly-arc-flash

As for being protected by the installation, move away from the consumer unit and
the wiring will help to some extent. But protective devices on the installation
might not always come to your aid, i've had an MK RCD fail closed at home in the
past couple of years (only discovered at a routine test, it could have been
faulty for a year or more) and come across a handful of MCB's, even low voltage
ones that have failed in various states including closed and incapable of
opening either manually or under fault conditions, all from various reputable
manufacturers.

http://ecmweb.com/arc-flash/case-deadly-arc-flash

--