Solutions defined with detail in that www.niceic.org.uk .pdf
document demonstrate techiques that have been standard or are slowly
becoming standard most everywhere in the past 30 years. This was
required in North America starting about 1970. Best way to address
electric safety starts by not worrying what you do or do not use in the
bathroom. That picture of a human in a bathtub using a hairdryer to
blow a sailing boat is what you - the owner of a building - must
address.

Start by putting all incoming electrical service on a GFCI - also
called RCD. One that trips at leakage currents lower than a building
wide RCD. These 'one circuit' type RCDs should trip at something
around 10 mA. This mA number will vary with different countries and
codes. But any bathroom with electricity should have a dedicated
GFCI/RCD type protector regardless of whether required by local codes.

jon wrote:
"Owain" wrote in message
...
To take an admittedly extreme and theoretical example, and I do not
recommend this in practice, you should stick a 240V live cable in your
mouth while standing in the bath and not feel the slightest tingle
PROVIDED that the bath (and thus you) was also at 240V through the
equipotential bodning.

Cheers, the mother-in-law visits on the weekend, i'll test your theory then.