New electrical consumber units in escape routes

[Suttonfire]

Hi All,

It has always been my understanding, as per approved guidance etc, that fixed electrical installations (consumer units etc) should not be sited within escape routes in the common parts of blocks of flats etc (should instead be housed within a fire resisting structure).

However, one of my clients has queried this in relation to recently installed units which a made of non combustible materials and incorporate RCD's (all subject to suitable periodic inspections etc). I would appreciate views on whether a modern installation, which incorporates these features, really requires enclosure within a fire resisting structure. Thanks

[Jim Scott]

I come across this quite often and meet varying responses.

My view is that I would not be too concerned about small single consumer units, particularly where they are new and non combustible.  Of course there is a line where this becomes not ideal, particularly with large intakes and/or multiple units (invariably increasing the probability of failure).

Also, the consideration of fuel loading with the staircase.  Non-combustible stairs, in a sterile, well managed environment?

There is an argument to suggest that providing an FR enclosure is providing a degree of fre loading, depending on its construction.

Lastly, the practicalities of such an enclosure.

As usual, it's a little bit of a cop out, although I feel everything should be judged on an individual, holistic basis.

[Dinnertime Dave]

Lacors says -

'Gas or electric meters and/or distribution boards should ideally not be sited in escape routes. However, it should be possible to relax this providing any gas meter is installed in accordance with the gas safety regulations and any electric meter is installed and sited in accordance with current IEE regulations. It is considered best practice to enclose such equipment in fire-resisting construction'.

ADB says  -

In single stair buildings, meters located within the stairway should be enclosed within a secure cupboard which is separated from the escape route with  fire-resisting construction.

[kurnal]

The recent change to wiring regulations in respect of the construction of consumer units only applied to domestic premises. Whether this applies to equipment installed in communal areas (including the Landlords supply) should be considered. In new builds usually there is a central cupboard in which each dwelling has its own consumer unit and meter fed from the 3 phase intake, representing a whole mass of pvc  insulation and potential energy / high fault currents.   In my humble opinion such multiple installations should be enclosed in a cupboard of fire resisting construction as per ADB.

If each flat has its own electrical cupboard then the risk should be much less but there will still be a communal intake and landlords supply.