Most things that put off enough voltage to require one of those probes arc through air at that distance. If it's close enough for a clusmy person to short somet

Most things that put off enough voltage to require one of those probes arc through air at that distance. If it's close enough for a clusmy person to short something, it's already either blown up or the insulation is thick enough to withstand some awkward poking with a probe (or its submerged in an oil or other nonpolar solvent).