Agree - consideration has to be made about who the warning is intended for.
The average punter has their own definition of low/high voltage which is different again to any definitions from the electric/electronic industries in Australia/Britain/Europe/Mars/USA - and would usually be something along the lines of batteries are low voltage, anything that can kill is high voltage.
You DO NOT represent the electronics community at all. I already quoted a source that the US electronics industry consider HV to be anything over 50VDC. See below for more and some evidence that the EU also consider things differently with electronics.
I did try to find the Australian standards, oddly searching for "Australian electronics standards" or the like has google change the search to "electrical". Best I can find so far is ACMA stuff which is telecoms and generic Australia standards info. Cannot seem to find who maintains electronics industry documents, I'll ask around about that.
The underwriters laboratory (UL) standards for electronic devices, which is the US standard.
While the standards themselves are available for a fee, there are easy ways to see the basic ideas.
Like say this recent patenthttp://www.google.com/patents/US8638539
Typically, Underwriters Laboratories considers lower voltage circuits, typically 42.5VDC or less and 30VAC or less, to be contactable by a person.
24VDC is a very common operating voltage in lighting controls, so it is common to find the relay coil being driven from a 24V supply. Most commercial relays are Underwriters Laboratories listed or rated for common U.S. operating voltages, e.g., 120VAC or 277VAC, because the physical spacing between the low voltage coil and the high voltage relay contacts meets Underwriters Laboratories spacing requirements
Seems pretty obvious to me, UL consider 24V DC to me LV, and 120VAC or 277VAC to be HV. In the US having stuff in your house that doesn't meet Underwriters Laboratories standards means the insurance won't pay out if the device was the cause of the fire.
How about the repair instructions for an air-conditioner sold in the Netherlands ?http://www.carrier.nl/~/media/Product_pdfs/42-serie/42NQV-G/04-Bediening-OM/storingscodes.ashx
... voltage between + – terminals of the C14 (“CAUTION HIGH VOLTAGE” is indicated.) electrolytic capacitor
(500μF/400V or 760mF/400V) on P.C. board ...
Labelled on the PCB inside a metal box, inside the air conditioner cabinet, where the customer couldn't get to it. And yet clearly Carrier consider 400V to be high voltage, better go tell one of the world's largest air conditioning companies they have it wrong.
I'm sure somewhere I have a heatsink that is live with 400VDC on it that is either stamped or sticked with high voltage warnings.