Posted By Ken Taylor There is a problem in the use of the term 'illegal'. Whilst 240v is less safe than a lower voltage, the issue is one of Codes of Practice, risk assessment and whether the employer is meeting the Electricity at Work Regulations and discharging a duty of care under other health and safety law. For a start, you could read the free publication INDG231 'Electrical Safety and You' (from the HSE on 01787 881165) - which contains a useful list of other publications on the subject.

Posted By Richard Peters I can't see that the use of 240v equipment is automatically illeagal, but the Electricity at Work regs 1989 do place an absolute duty of care on the duty holder. With reference to the use of low voltage equipment, surely this must be safer to the user in the event of electic shock? 110v centre earth equipment will only have 55v to earth, less than 1/4 that of 240v equipment. This will reduce the current passing through the body by a similar factor, maybe from a fatal 100mA to an uncomfortable 23mA.

Posted By Richard Peters I understand the power and increased amperage requirement associated with the tools in use and I appreciate the increase in voltage drop and loadings on connections, etc. From a fire safety point of view I must agree with you. As regards the risk from electocution, however, there must be a point where a reduction in voltage makes a system safe. For a constant resistance to earth (taking like for like, a path through the body) a lower voltage will result in a lower current. There must surely be a point where the result is no injury. Taking the extreme, a 1.5v, 3v, 6v or 12v cell will not do any harm if held between the fingers. Granted, this is d.c. but I would not like to do the same with 240v. If 110v centre earth (i.e +/-55v) is not the cut off, then where does it become safe?

Posted By Jack Martin, why do you think its an “urban myth”. Richard is surely correct. Current (through the body) is proportional to the Voltage applied across it as Mr Ohm might have put it. Increase the voltage and a greater current will pass and it is this current which inflences the outcome. And for a given voltage this depends on the resistance. V=IR and all that!

Posted By Brian Dawson Edward, why forget the physics, especially when you seem to be singing from the same hymn sheet. Surely better than counting the dead!