IEC 60364 Table 48A

davezawadi (David Stone):

I think there needs to be a little reality here. The suggestion that RCDs do not protect direct contacts sufficiently is fundamentally untrue. How many DEATHS in the last 10 years due to RCD failure and direct contact, however wet or otherwise the environment? I have never heard of one so let's say one every 3 years, just for fun, and finding out the actual number is very difficult. There have been a number of suicides, but that is very different, and taking an appliance into the bath with you is not an accident, and unless the bath is well Earthed not particularly dangerous as there is not a lot of circuit and a body has more resistance than the water surrounding it unless very pure. I would therefore argue that our UK protection is many times better than our fire protection so must be considered satisfactory. This may not be the case in other countries, but we are well developed and near the top of the Health and Safety tree of quality and implementation.


If you want to use a mains voltage in a very wet location, with dodgy flexible cables and no RCDs, that is your choice. Any sensible person in such an environment would push the test button, or perhaps use an RCD socket or possibly have additional bonding. I suggest that the place where this would be seen is Farms, these are places with lots of water and sometimes not very good electrics. This is far from the major cause of Farm accidents, to either people or livestock. Farming is a dangerous occupation, but mainly due to machinery and the problems of working fields on slopes. Quite close to the worst things after machinery is animals, they are very unpredictable and have all kinds of weapons. Wet wiring needs to be at least IP44 and if sprays etc. then IP67, the same for equipment which may get wet.


If Mr (Mrs, Miss etc.) Brooke really wants to discuss this I think it would be as well to be very open as to why. Standards committees (and I have served on some) are very aware of possible problems, but also well-grounded in reality as I suggest above. For what reason does he think the standard is not satisfactory and what is the EVIDENCE behind the assertion? If that is forthcoming I am sure that getting the standard changed is quite straightforward, if slow and requires effort.


Kind regards


David CEng etc.

I had indirect contact in mind.


But, let me ask you this.  What deficiencies were so profound in the UK regs such that AFDDs are soon to be mandatory? What were the statistics, reasoning, inference and voting in the standards committees supporting AFDDs?   


I'm not sure what why I'm not being open about?.      

davezawadi (David Stone):

I think there needs to be a little reality here. The suggestion that RCDs do not protect direct contacts sufficiently is fundamentally untrue. How many DEATHS in the last 10 years due to RCD failure and direct contact, however wet or otherwise the environment? I have never heard of one so let's say one every 3 years, just for fun, and finding out the actual number is very difficult. There have been a number of suicides, but that is very different, and taking an appliance into the bath with you is not an accident, and unless the bath is well Earthed not particularly dangerous as there is not a lot of circuit and a body has more resistance than the water surrounding it unless very pure. I would therefore argue that our UK protection is many times better than our fire protection so must be considered satisfactory. This may not be the case in other countries, but we are well developed and near the top of the Health and Safety tree of quality and implementation.


If you want to use a mains voltage in a very wet location, with dodgy flexible cables and no RCDs, that is your choice. Any sensible person in such an environment would push the test button, or perhaps use an RCD socket or possibly have additional bonding. I suggest that the place where this would be seen is Farms, these are places with lots of water and sometimes not very good electrics. This is far from the major cause of Farm accidents, to either people or livestock. Farming is a dangerous occupation, but mainly due to machinery and the problems of working fields on slopes. Quite close to the worst things after machinery is animals, they are very unpredictable and have all kinds of weapons. Wet wiring needs to be at least IP44 and if sprays etc. then IP67, the same for equipment which may get wet.


If Mr (Mrs, Miss etc.) Brooke really wants to discuss this I think it would be as well to be very open as to why. Standards committees (and I have served on some) are very aware of possible problems, but also well-grounded in reality as I suggest above. For what reason does he think the standard is not satisfactory and what is the EVIDENCE behind the assertion? If that is forthcoming I am sure that getting the standard changed is quite straightforward, if slow and requires effort.


Kind regards


David CEng etc.

I had indirect contact in mind.


But, let me ask you this.  What deficiencies were so profound in the UK regs such that AFDDs are soon to be mandatory? What were the statistics, reasoning, inference and voting in the standards committees supporting AFDDs?   


I'm not sure what why I'm not being open about?.