With the 18th Edition being in for nearly a year now there are still issues being highlighted with domestic and commercial clients.
The biggest change is the installation of surge protection, arc fault protection and the requirements for RCD protection.
A 30mA is now required on all sockets rated up to 32A rather than 20A also, they are needed on all final circuits supplying luminaires within residential buildings.
Exceptions are not permitted in dwellings
One of the most significant changes in the 18th edition is the overhaul of Section 443 which deals with overvoltage caused by atmospheric conditions, i.e. lightning. Where the need for protection against transient overvoltage used to be defined by the AQ criteria – effectively considering the frequency and likelihood of lightning strikes – these have now been replaced by criteria considering the potential consequences of lightning strikes. This will expand the scope where protection is required, except in certain single dwelling units, and once again these additional systems will need to be thoroughly tested.
In laymen terms we now must consider the damage cost to equipment from a lightning strike if you consider the amount of electronic equipment that is in most homes these days then the additional cost of a few hundred pounds for surge protection is insignificant.
With the rise in electrical vehicles section 722 of the regulations has been updated to take into consideration the growth in this market.
Arc Fault Protection
The use of Arc Fault Detection Devices conforming to BS EN62606 is a recommended method for providing additional protection against fire caused by arc faults in AC final circuits. If used, AFDDs shall be placed at the origin of the circuits to be protected i.e. in the consumer unit or distribution board. Examples of locations where such devices can be used include: Premises with sleeping accommodation such as dwellings, hotels etc Locations with a risk of fire, because of the nature of activity involves flammable materials Wooden buildings and structures made from combustible materials Fire propagating structures e.g. high rise buildings Locations with irreplaceable goods: archives, museums etc
ONLY USE APPROVED PARTS
Devices and components used in low voltage assemblies e.g. Consumer Units, Distribution Boards etc. must only be those that have been declared suitable for that purpose by the manufacturer of the assembly.
Or put another way: use manufacturer approved parts, don’t mix brands of devices or control items. If in doubt, ask the manufacturer of the assembly to confirm compatibilities.
One major item is in the improvement of cable security in the case of fire. Wiring systems throughout the installation (as well as escape routes) must be supported by fixings, or in carrier systems such as appropriate types of steel tray, or trunking etc. that will protect systems against premature collapse during fire. Previously this applied to escape routes only.
If you have any concerns over the electrical installation within your house or place of work, then please contact our office on 0208 306 6100 where one of the team will be able to assist you.