Electrical projects

One standard, whatever the building

BS 7671, the IET Wiring Regulations, applies whether the job is a socket in a bungalow or a distribution board in a warehouse. The 18th Edition including Amendment 2 of 2022 is the current version, and the practical effect is that the same discipline about design, inspection and testing runs through every job regardless of its size.

What changes with scale is the coordination, not the standard. A larger installation brings containment routes, phase balance, discrimination between protective devices and a longer test schedule, but the rules being satisfied are the same ones.

Life safety, and why it is separate

Fire detection, emergency lighting and alarm systems sit alongside the general installation but are governed by their own standards and their own testing regimes. At the Linkage training centre we delivered a complete electrical and life safety installation, covering addressable fire detection, intruder alarm, data and containment as one package.

Keeping those systems with the main electrical contractor avoids the commonest problem on a mixed project, which is a gap between trades where each assumed the other was providing the supply, the containment or the certification.

Lighting is usually the quickest saving

Lighting is often the easiest thing to improve in a commercial building, because the old technology is genuinely inefficient. A 400 watt metal halide high bay replaced by a 150 watt LED saves the difference every hour it burns, and a busy building gets through a great many hours.

Two things are worth specifying rather than accepting. Colour rendering matters wherever colour is part of the work, in retail, hospitality or anywhere stock is inspected, and controls matter in spaces used intermittently, where presence detection saves more than the lamp change does.