AFDDs were adopted in the latest regulations here because of timber frame construction being popularised and because of more apartments and taller buildings being envisaged.
Also, I think the cost and practicality of adding AFDDs has just dropped to the point that they're no longer a major consideration anymore, so they're being added.
The current regs I.S. 10101:2020 adopted them.
The USA was always much, much more concerned about fire hazards, primarily due to the construction techniques used there - i.e. all-wooden buildings and also because of the prevalence of high rise.
A smouldering circuit in a wooden frame building can be catastrophic, where as a similar incident in a block and plaster wall can just burn out.
That's primarily why you have had requirements for metal conduit for all cables and so on in the US whereas in Europe that has been far less of a concern in most circumstances.
AFDD technologies have just also come of age too and become cost effective and practical to install. The cost vs the benefits didn't necessarily add up in the context of this part of the world, given the construction standard differences, other than in highly sensitive locations like high rise, until quite recently.
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With regard to Schuko, as counterintuitive as it may sound, the original logic of it was that grounded / earthed appliances *should* be able to be plugged into non-grounded sockets, but that 'Class 0' appliances (i.e. old appliances that had no double insulation or earth protection - banned since the 1970s) should only be able to be connected to non grounded sockets.
The design of wiring in houses was such that grounded sockets were in areas with conductive floors, sources of water etc e.g. kitchens and bathrooms, perhaps hallways etc, but that in areas with wooden floors, non-grounded sockets were allowed.
So, you could plug a Schuko (or a French/Belgian) grounded plug into any socket in the house, but you could not plug an old Class-0 appliance plug into such a socket as it wouldn't physically fit, so you were limited to using those appliances in rooms that were naturally insulated.
It was a pre 1950s concept of optional grounding safety. Also, people simply wired Class-0 appliances to Schuko plugs, without connecting the ground, so ended up using them in very risky contexts like wet areas.
I don't think the ESB here ever accepted that mythology as all socket outlets, whether BS or Schuko were grounded.
AFAIK, the same concept applied with BS546 systems i.e. the old BS196 2 pin outlets were in theory only ever to be used in safe locations that didn't need grounding, and were a different pin gauge to the 3-pin variety, so you couldn't plug a 2 pin plug into a 3 pin socket in the old British system, but a kludge of adaptors made it very possible, and dangerously so.
Over complicated systems that worked counter intuitively. It made far more sense to just have all grounded sockets and ban Class 0 entirely.
The current UK system (introduced in the late 40s but only mandated in the 60s) was designed to basically render all the previous systems entirely incompatible with it and force upgrades, hence the rectangular pins and so on.[this post was last edited: 7/30/2021-15:08]
Also, I think the cost and practicality of adding AFDDs has just dropped to the point that they're no longer a major consideration anymore, so they're being added.
The current regs I.S. 10101:2020 adopted them.
The USA was always much, much more concerned about fire hazards, primarily due to the construction techniques used there - i.e. all-wooden buildings and also because of the prevalence of high rise.
A smouldering circuit in a wooden frame building can be catastrophic, where as a similar incident in a block and plaster wall can just burn out.
That's primarily why you have had requirements for metal conduit for all cables and so on in the US whereas in Europe that has been far less of a concern in most circumstances.
AFDD technologies have just also come of age too and become cost effective and practical to install. The cost vs the benefits didn't necessarily add up in the context of this part of the world, given the construction standard differences, other than in highly sensitive locations like high rise, until quite recently.
---
With regard to Schuko, as counterintuitive as it may sound, the original logic of it was that grounded / earthed appliances *should* be able to be plugged into non-grounded sockets, but that 'Class 0' appliances (i.e. old appliances that had no double insulation or earth protection - banned since the 1970s) should only be able to be connected to non grounded sockets.
The design of wiring in houses was such that grounded sockets were in areas with conductive floors, sources of water etc e.g. kitchens and bathrooms, perhaps hallways etc, but that in areas with wooden floors, non-grounded sockets were allowed.
So, you could plug a Schuko (or a French/Belgian) grounded plug into any socket in the house, but you could not plug an old Class-0 appliance plug into such a socket as it wouldn't physically fit, so you were limited to using those appliances in rooms that were naturally insulated.
It was a pre 1950s concept of optional grounding safety. Also, people simply wired Class-0 appliances to Schuko plugs, without connecting the ground, so ended up using them in very risky contexts like wet areas.
I don't think the ESB here ever accepted that mythology as all socket outlets, whether BS or Schuko were grounded.
AFAIK, the same concept applied with BS546 systems i.e. the old BS196 2 pin outlets were in theory only ever to be used in safe locations that didn't need grounding, and were a different pin gauge to the 3-pin variety, so you couldn't plug a 2 pin plug into a 3 pin socket in the old British system, but a kludge of adaptors made it very possible, and dangerously so.
Over complicated systems that worked counter intuitively. It made far more sense to just have all grounded sockets and ban Class 0 entirely.
The current UK system (introduced in the late 40s but only mandated in the 60s) was designed to basically render all the previous systems entirely incompatible with it and force upgrades, hence the rectangular pins and so on.[this post was last edited: 7/30/2021-15:08]
