Do we have to fit AFDD's in domestic installations?

[HappyHippyDad]

I can't find any really up to date threads on whether we have to fit AFDD's.

I am specifically talking about in a domestic premise. I can see that 421.1.7 shows where an AFDD HAS to be fitted (i.e in one of the 4 bullet points), but then it says below ( the bullet points) it is 'recommended' that AFDD's are fitted in ALL premises for socket outlets.

The Napit Webinar (02/11/2022) kind of skips lightly over this point. At 11 mins and 25 seconds he says something along the lines of 'it is up to the designer whether to use the recommendation of using AFDD's'.

It clearly is not mandatory otherwise the reg would not state the 4 examples of where it actually is mandatory. So it is actually optional, but there isn't any criteria given to help you decide whether or not you should fit one.

Does anyone have any clarification on this?

 

[Vortigern]

I am sorry but the cynic in me observes the fact that the people making AFDD devices sit on the board recommending them. That alone makes me reticent. Then the cost. Most clients will baulk at the cost. On top of that there was a somewhat torrid thread from our partners over the pond re the matter of AFDD suggesting that we do not need them as with our voltage and the use of RCD we already have systems in place that will detect an arc fault and AFDD are superfluous. Essentially, I agree with that contention.
I could take the view that lets throw everything and the kitchec sink at "safety" and cover my derriere. As long as the client can afford it why should I think about these heady matters just comply and charge the customer.
Pragmatically it is not as simple as that. Most clients, domestic wise, will not buy it.
Bottom line; there is currently no neccesity to fit AFDD right now. But....as in the case of RCD, there will be. Whats not to like? We bring in a slight change to the regs, we can charge for a whole new set of OSG, BS7671 and bingo on the product! This will become invevitablly compulsory, at the moment it is not in average domestic wiring. If there is any ambiguity in the definitions that is JPEL's fault not mine.

 

[freddo]

On top of that there was a somewhat torrid thread from our partners over the pond re the matter of AFDD suggesting that we do not need them as with our voltage and the use of RCD we already have systems in place that will detect an arc fault and AFDD are superfluous. Essentially, I agree with that contention.

Another reason is our house wiring doesn't use aluminium cable (except for a tiny number of examples) that is far more likely to suffer arcing than copper wiring.

 

[suffolkspark]

Ive just put a board full of afdds on a thatch re wire as im not on a price so thought even if it gives 1% extra safety im doing it, (im an ex fireman and they burn well ) but the rest of my jobs i wont, they do have Bluetooth though so you can communicate with them with your phone with the hager app

 

[AJB Temple]

An architect friend of mine is just doing a large thatch extension on a job. He's specified AFDDs and I agree it makes a lot of sense with thatch. It's very difficult to get useful data on the cause of electrical fires. Anecdotal evidence seems to suggest that it is rarely faulty wiring in the UK (if done properly by skilled electricians to regs). Faulty appliances such as dodgy washing machines seem to get fingered quite a lot. These things generally are low priced and poor quality and end up in rentals and social housing. Arguably that is where protection is most needed and least likely to occur.

 

[default]

I can't find any really up to date threads on whether we have to fit AFDD's.

I am specifically talking about in a domestic premise. I can see that 421.1.7 shows where an AFDD HAS to be fitted (i.e in one of the 4 bullet points), but then it says below ( the bullet points) it is 'recommended' that AFDD's are fitted in ALL premises for socket outlets.

The Napit Webinar (02/11/2022) kind of skips lightly over this point. At 11 mins and 25 seconds he says something along the lines of 'it is up to the designer whether to use the recommendation of using AFDD's'.

It clearly is not mandatory otherwise the reg would not state the 4 examples of where it actually is mandatory. So it is actually optional, but there isn't any criteria given to help you decide whether or not you should fit one.

Does anyone have any clarification on this?

Your right there are certain situations where they shall be fitted, which seems quite clear. Anything other than this is a recommendation which means it does not need to be done

 

[brianmoooore]

Anything other than this is a recommendation which means it does not need to be done

Right up to the point when something disastrous happens that is determined wouldn't have happened if an AFDD had been fitted

 

[default]

Right up to the point when something disastrous happens that is determined wouldn't have happened if an AFDD had been fitted

As long as you have followed the regulations and don't decide yourself what constitutes as a recommendation then there is no come back. The regs aren't there to trick you. They may seem to contradict themselves sometimes but a recommendation is a recommendation. When it comes to AFDDs they state where you shall you them, and even define what they mean and the recommend where else they could be used. If you decide that your not sure then use them everywhere then you won't need to worry.

 

[mainline]

Ive just put a board full of afdds on a thatch re wire as im not on a price so thought even if it gives 1% extra safety im doing it, (im an ex fireman and they burn well ) but the rest of my jobs i wont, they do have Bluetooth though so you can communicate with them with your phone with the hager app

You will have to let us know if they give any problems.

 

[newfutile]

Recommended does not mean you have too,however i always plan a defence in case this is questioned at any time .mine would read : it does not state “shall” (unless it does) ,good workmanship ,following equipment manufacturers instructions , checking all screw fit joints and of course proper inspection and testing with all results as expected or calculated . You could probably go further than this with proper cable supports,safe zones rcbos. For lighting for instance a series arc current (with led lamps) will most likely never be reached .

 

[pc1966]

Ive just put a board full of afdds on a thatch re wire as im not on a price so thought even if it gives 1% extra safety im doing it, (im an ex fireman and they burn well ) but the rest of my jobs i wont, they do have Bluetooth though so you can communicate with them with your phone with the hager app

That is a very good example of where AFDD would be a sensible choice even though nor mandated.

Also I suspect owners of thatched roof properties can probably afford it, if not then they can't afford to maintain the thatching!

 

[HappyHippyDad]

Update from napit technical team relating to when you have to fit AFDD in domestic premises and it's view on the term 'recommended'...

"Thanks for watching the AFDD webinar, we are pleased you enjoyed it. The term recommended is not a new requirement for AFDDs, if you refer to the 2018 Edition of BS 7671 (blue copy) Reg 421.1.7 recommends AFDDs for all AC final circuits. Unfortunately, with so many different installations and different user types it can only be a decision made by the designer after considering all aspects."

Basically they're saying it's up to us if we fit them. In reality, hardly anyone will fit them at present due to the cost. If there is a fire due to electrical arcing and it goes to court, the IET will say 'well we recommended it." A disappointing reply to my thorough question (although I pinched the wording from @Julie 's professional sounding post )

I think, as part of my quote I will recommend AFDD's to be fitted. I'll perhaps write a small amount about there use, and then leave the customer to make the decision.

 

[Dustydazzler]

Never fitted one and until they become common place at less than 1/2 the price I won't be fitting any

 

[HappyHippyDad]

Never fitted one and until they become common place at less than 1/2 the price I won't be fitting any

Neither will I Dusty, but the point being... If there is a fire due to arcing then it will be the electrician who is deemed to be at fault because the IET have covered themselves with the word 'recommended'. I will now continue this bottom covering exercise by also adding the word 'recommend' in my quote.

Then, in 2-5 years we can all fit them as standard when they come down in price.

Then, we can all talk about the latest addition to the rcbo/afdd, with something else added to it which costs a fortune etc etc .

 

[Midwest]

Wonder if an AFDD would of worked here

 

[brianmoooore]

RCD would have taken care of the above.