Last updated: 08.02.19

BS 7671 18th Edition Wiring Regulations Guide

BS7671, or The Regs as they’re known in the trade, are one of the most important documents for electricians in the United Kingdom, and in 2018 they were updated. In this article, we’re going to cover the basics of the 18th Edition. This includes what it covers, who it’s for, and what the big differences are between the latest publication and the previous one.

What is BS7671?

BS7671, formally ‘Requirements for Electrical Installations. IET Wiring Regulations’ is a British standard for the installation of electrical wiring. This applies in most domestic and commercial applications of all types, and covers all voltages up to 1000 volts AC or 1500 volts DC. It is a several hundred page document that explains and recommends how installations should be carried out to ensure that they of a high standard, primarily with safety in mind, but also in terms of effectiveness and efficiency. BS7671 isn’t a law or necessarily a legal requirement, but it is treated in a similar way given how comprehensive and widely recognised as an authority it is. Organisations from accrediting bodies to insurance companies will want to see that an electrical installation has been carried out to the BS7671 standard.

What is the latest edition of the IEE/IET wiring regulations?

The regulations are periodically and quite regularly updated to reflect new developments and best practice. Indeed, the 17th Edition, which was first published in 2008, received small updates even into 2015. The 18th Edition, also written as BS7671:2018 was first made available in July of 2018, and as of January 2019, it is now the official and current standard that all electrical installations should follow, which includes the changes it makes. We will look at some of these later in the article.

Note: BS7671 is still frequently known as the IEE wiring regulations, but the Institution of Electrical Engineers (IEE) and Institution of Incorporated Engineers (IIE) joined together in 2006 to form the IET. Therefore the proper name is the IET Wiring Regulations.

Do you need the 18th edition?

You may be asking yourself “Why do I need to know about BS7671 18th edition changes”? The answer is quite simple, in that just about every electrician in the United Kingdom needs to know about the BS7671 regulations, and they need to know all of the relevant updates too. As this standard sets the requirements for most electrical wiring installations in the country, it’s simply essential knowledge, and not knowing the latest could mean that you don’t have all of the knowledge you need to do the job properly.

BS7671 applies to the wiring installation you’re working on, and the simple fact is that if you don’t have the 18th Edition regulations, or don’t know what they include, then your installation may not meet this standard. It could therefore be unsafe, or inefficient, and there are all manner of potential knock on effects from this. If you are installing electrical wiring in the UK, then you need to know what the 18th Edition is, and the changes it brings.

Generally, most good electricians will have a full copy of the latest Edition of the regulations, but this isn’t always quite enough. It’s all very well having access to what the document says, but do you actually know it? This is why many registering bodies, agencies and larger organisations require that electricians working with them, for them or under their logo have some form of qualification that says that they understand BS7671 to the latest edition. If you don’t have this, then you might find it more difficult to get work, as larger businesses tend to require this at a minimum, and individuals who are looking for an electrician will often look for the logo of a governing body or association. Again, these will generally require this proof of BS7671 knowledge.

Generally, those who do need to know about the wiring regulations, and prove this, will take a course on the subject, which usually concludes with some sort of test to demonstrate knowledge. Here at Virtual College, we’re pleased to be able to offer accredited courses in BS7671, designed specifically for people who need to demonstrate their knowledge of it for their job. These are accredited by leading authorities, and are available as comprehensive courses for newcomers or those who’ve not trained in some time, as well as top-up courses for those that just need to know about the 18th edition changes.

It’s always important to remember that BS7671 applies to the electrical installation itself - not a person. So while you can become fully trained in BS7671, with completion of an accredited course proving it, you do not have it as such.

What is in the 18th edition?

So what are the 18th edition wiring regulations changes? In this final section, we’re going to go through some of the more significant changes that you’ll find in the most recent edition of the regs.

New Scope

Compared with the 17th Edition, the 18th Edition has an ever so slightly larger scope. It now includes electrical shore connections for inland navigation vessels.

New Requirements

Overvoltage protection, and cable supports are two of the new requirements that you’ll find in the 18th Edition. Overvoltage protection is now something that any wiring installation should include unless a risk assessment is carried out. If this risk assessment finds that there are any particular risk factors, such as severe injury, loss of life, or disruption to public services, then overvoltage protection should be included. Metal cable clips have previously been mandated at fire escape routes to prevent collapse of wiring in a fire, but these are now to be installed everywhere, bringing a new requirement to the electrician’s toolkit.

New Technology

One of the most significant reasons for a new edition being published is new technology. Arc fault detection devices (AFDDs) have been around in North America for quite some time, but have only recently started to be used commonly in the UK. It’s now recommended that these devices are installed at distribution boards and all consumer units.

New Aims

The final point is that BS7671 now has an additional aim to it. The standard has always been focused on what makes an electrical installation safe and effective, but it now also makes recommendations on how to make the wiring more energy efficient and therefore environmentally friendly. This follows a trend with many other standards also catching up with the modern drive to be more conscious about energy use. It’s very likely that in future editions and revisions, this aspect will be even more heavily pushed.

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