In medical locations within the scope of Section 710, Regulation 710.421.1.7 modifies Regulation 421.1.7 in relation to those locations.

I guess in some premises like this there could be areas that are not a 'medical location' as defined in BS 7671, in which case Regulation 421.1.7 would generally apply to the installation in those areas as it would to a similar location in other premises?

NE-ELEC-12 said:

and all other rooms would fall under group 0 and require a risk assessment

Therefore, perhaps but only if they are 'medical locations' of Group 0 as defined. If they are not a 'medical location' then back to Regulation 421.1.7 in this regard.

A learned member of this forum suggested that AFDDs were not required in Group 1 and 2 locations simply because some of the very specialized equipment used in such locations may cause the devices to nuisance trip, which could result in a critical situation.

Someone would need to assess the risk in the group 0 location, if there is one identified, which, inter-alia, would consider the effect of loss of supply if the devices were employed.

Only my opinion, but for what it is worth, I strongly believe that it was ill-conceived for 421.1.7 to mandate their use. The deployment of the devices are purported to reduce the risk of arcing and subsequent ignition but they also have shortcomings. That being the case, their use should have rested squarely in the bailiwick of the fire risk assessor/fire engineer in consultation with other relevant parties in the design team.

I guess that can still be done and if it is considered that the devices are actually required by BS7671 but would be more trouble that their worth, the matter can be written up as a departure on the Electrical Installation Certificate.

In my opinion, "bedrooms, kitchen, ..." do not amount to a medical location. By contrast, a treatment room might be one (those sort of facilities may well be located elsewhere on the premises).

However, there is an argument that the hospice is a form of care home: there are bedrooms and communal spaces for the clients for whom care is provided. On the other hand, most people in a care home reside there (although they may be used for respite or convalescent care, or even terminal care) so a hospice and a care home may be distinguished.

I entirely agree with lyledunn in as much as the benefits of these devices are not proven. FWIW, I am in the process right now of installing a new consumer unit in my own home and I shall not be installing them.

All things considered on the basis of the information provided, I do not think that AFDDs are required and neither is a risk assessment.

there is an argument that the hospice is a form of care home:

I debated that with myself, but given that BS 7671 doesn't give a definition of a "care home", normal usage applies, and in normal usage "care homes" are distinct from "nursing homes". (i.e. care homes that also provide medical support). As care homes are listed but nursing homes aren't there must be a significant distinction there. I reckon a hospice is probably closer to a nursing home than a care home (or in some cases possibly somewhat closer to a normal home, if with a lot of extra support on the side).

    - Andy.

That is a very valid viewpoint, but might a "nursing home" be a subset of "care home"?

This is a very interesting debate.

Are AFDDs (inclusive of RCBO) a good idea. Yes....However


Been used is Germany for about 10 years now so they are not really a new technology.

It will protect against one type or Arc not both Series and Parallel

The AFDD is to help protect against issues created by substandard electrical appliances being purchased in the UK from abroad and especially on the Web (look up underwater 4 way extension leads on Ebay, Amazon or Wish)  



BUT
AFDDs could and will trip on nuisance devices thus causing nuisance tripping
Medical or Life critical system should not be connected to AFDDs resulting in no power.  A lot of Medical systems with have secondary power supply of even a battery backup

I strongly believe that better fire detection should be implemented like all dwellings having interlinked smoke/heat alarms as is the case in Scotland.  



I look forward to the AFDD debate continuing

The situation in Germany is interesting - AFDDs first appeared in VDE 100 in 2016, and after a short period of grace for the old regs they became compulsory for sleeping accommodation, old folks homes und Kinder Gaertner, places storing flammable materials etc. and such installation was mandatory to claim compliance with the regs.

As in the UK the German wiring regs are not strictly a legal requirement, but many things mean they may as well be, and unlike in the UK you will need good luck in finding a German Sparks willing to deviate far from the text.. So in they went at least on the new builds.

However, from 2019, there has been some serious mud thrown into the water, as the installation of AFDDs is now just one of a range of measures that may be taken to reduce the risk of fire, and not always the main one, and a risk assessment is recommended  to decide the best course.

I presume this is to allow their omission for cases where problems of unwanted tripping would cause more harm than the possible good or where  other measures (fire supression/ sprinklers or buildings made of concrete ?) mean a serious fire from an arc fault is most unlikely.

There was fairly heated  discussion in the German trade apparently when they came in, but I am mostly out of that loop these days (example here)

Now in reality, having spent a few years to get folk attuned to the "AFDDs good" message I will be surprised if there will  now be a rash of Germans taking them back out, but  it does show a highly  unusual trend for Germany, that of rowing back on a hard and fast rule....

Source here - in German of course.  A non-German speaker may feed the paragraphs under the section titled "Einbau von AFDDs nicht mehr verpflichtend" into google translate for more.

I am still looking for the evidence of fire reduction, but as yet it is not showing through, either in the US figures or in the German ones...

Mike.

Edited for Grammer ' A non-German speaker..' apologies

mapj1 said:

Source here - in German of course.  non German speaker may feed the paragraphs under the section titled "Einbau von AFDDs nicht mehr verpflichtend" into google translate for more.

Or open the page in Chrome or Edge and the option to translate the web-page to English will be provided.

In my opinion at present time for a dwelling a CU would be good with all RCBOs and SPD type 2 & 3 until there overwhelming evidence to the contrary.  This should be the case for a home or a rental.  I also feel that in the UK well England we needs to increase fire detection in the average home and rental sector by interlinking smoke/heat/Carbon monoxide alarms. 

This does again pose another question.

Fire/Smoke alarm.  Advise is to exit property

CO alarm. Advise is to open all windows and exit property

I would suggest a highly distinction sound for smoke/heat to CO alarm would be advisable.  The interlinking of the CO and Heat and Smoke means there is a greater chance of detection as some fires give off more CO before there is smoke, while other fires give off more heat before flame. 

Sergio Fernandez said:

In my opinion at present time for a dwelling a CU would be good with all RCBOs and SPD type 2 & 3 until there overwhelming evidence to the contrary.

Ah yes, the £1k fusebox!

Would you not have a CO alarm only if there are solid-fuel or gas appliances in the house itself?