Do you think there is a problem with school electrical installations?

Sergio Fernandez said:

Should schools for under 16 years be granted special location status in BS7671?

Scope would have to include not just schools, but nursery/day care, perhaps scout huts, cadet centres, etc.

But I guess the question is, what is the "increased shock risk" that we are trying to mitigate against? (i.e. what's the evidence we need this?)

A final thought regarding BS 7671 is, wouldn't the same, or similar,  risks be prevalent in domestic premises in which children live? And if so, would BS 7671 be deficient if it didn't deal with those risks "by default" for homes?

There is a standard that covers H&S in laboratories/workshops etc. used in educational settings, and electrical safety (including for fixed installation in those locations) is considered: BS 4163:2021+A1:2022 Health and safety for design and technology in educational and similar establishments. Code of practice

gkenyon said:

Scope would have to include not just schools, but nursery/day care

Lets include the above criteria.  

Then lets consider that 30mA RCBO should give a safer instalation than one with MCBs.

With luminaire being replaced due to energy consumption/failure and that the EU have banned filament lamps and are in the process of phasing out t5 and t8 fluorescent tubes it stands to reason that more luminaries will be replaced for LED version.  The LED versions will naturally leak DC current to Earth.

RCBO could also help detect borrowed neutrals

RCBO could help detect imbalance between L and N

gkenyon said:

A final thought regarding BS 7671 is, wouldn't the same, or similar,  risks be prevalent in domestic premises in which children live? And if so, would BS 7671 be deficient if it didn't deal with those risks "by default" for homes

My opinion on this would differ as there could be 30 - 35 children in the classroon from different families and also children at home will be more familiar with their home enviroment.  Equally important would be visitors to the school.  Think of a parents evening or A summer fair when extention leads are trailled outside to power lights and music. 

We were not aware of reinforced autoclaved aerated concrete until the start of term was being delayed for several schools.

As parents/gaurdians and engineers we have a duty of care to all that are in education to make sure they are safe.  The rules in BS7671 should be written as if we are custodians of the UK wiring system.  The rules we help shape now will become our legacy. 

To be honest I'd go the other way. The aim of education is to prepare for the real world things that are out there, not to be hidden from them - if anything it is better to meet situations in a controlled setting you hopefully never need in real life - such as the majority of first aid training.

As one who deals a lot with teenagers (as an Assistant Scout Leader) I know very well the tricky balance between exposing youngsters to situations that stretch them  a bit, allowing them to enjoy a challenge,  and actually being reckless. It can go wrong very occasionally, as has been reported in the news recently.

However, the risks of electricity are way down the list compared to fires, gas bottles, pen knives, night hikes, food poisoning and general accidents of the 'fell out of a tree he was not meant to have been in in the first place' which are the majority. (And when they learn first aid, in among cuts and broken bones, sunstroke, car accidents and how to call 999 we do also mock up what to do in case of fire or electric shock)

Youngsters when exposed to a real potential danger generally rise to the event. The  ones who are busy drawing genitalia on the white board or throwing bits of paper at the air cadets during church parades are the same ones who are dead keen to learn knots once standing  at the top of a climbing tower, and are the most attentive when we are using power tools or axing firewood.

I'm not sure how adding RCD protection to the hall lights does anything other than add another failure mode  and may take money away from other safety activities like replacing a fraying doormat or changing water heaters to have safety thermostats. The sockets for those outdoor leads you worry about already have it.

M.

Hi Mike

I understand your point of view.  I also help out at Scouts in Watford as my son is in Cubs.  I really enjoy the way Scouts help shape the future of young people by giving them practical skills like Basic First aide encluding CPR and use of AED. 

Sergio Fernandez said:

Think of a parents evening or A summer fair when extention leads are trailled outside to power lights and music. 

BS 7671 has requirements (where applicable) for the parents evening or summer fair in Sections 711 (and possibly 740).

A school or similar environment is subject to Electricity at Work Regulations, and therefore ought to have a duty holder responsible for electrical safety, and has a duty to consider safety at such "events".

Sergio Fernandez said:

My opinion on this would differ as there could be 30 - 35 children in the classroon from different families and also children at home will be more familiar with their home enviroment. 

Isn't this countered by the fact that in a School, there is a responsible duty holder?

I can see that the actual design specification for a school ought to take some things into account that are not taken into account in other environments, but that doesn't mean BS 7671 is deficient? Indeed, BS 7671 has external influences BA2 and BA3 for the designer to consider, among a plethora of other external influences?

There may be parts of a School that have extra risks - cookery classes, various science labs, perhaps the gym, come to mind, but these I think are already handled by the relevant parts of the regs and the fact there is a more general H and S regime, as Graham points out.

And I think it would  be hard to write in to a BS something that was not either so general as to be useless or so specific as to be unhelpfully restrictive. 
If anyone it should be other authorities that decide that there are local rules for specific establishments, - much as potentially dangerous gas appliances are permitted at colleges that teach gas fitting so that the students have something to measure and  learn from...

Mike.

Should all circuits in schools be protected by a 30mA RCBO/RCD regardless of their use?  This would apply to new or existing circuits.

Absolutely not - schools are often large and complex electrical installations with many sub-mains/distribution circuits - putting 30mA RCD "protection"  on them would result in many unneeded disconnections and so create extra hazards resulting from the loss of power (everything from lighting to kitchen refrigeration), not to mention loss of teaching time.

   - Andy.