Last updated: 06.02.19

18th Edition what you need to know

Why is the 18th Edition update so important?

The 18th Edition of BS7671, the UK’s standard for electrical wiring installation, was released in 2018 and is now fully in force. It’s something that many thousands of British electricians will need to be aware of, and as a result, we’re going to take a look at some of the key points surrounding it. This includes the importance of familiarity with the regulations, some of the key differences between the 17th and 18th Editions, and how electricians can seek training to demonstrate their knowledge of this important information.

Who needs to know about the 18th Edition update to BS7671?

As a general rule, anyone working as an electrician in the United Kingdom should have comprehensive knowledge of the most recent edition of BS7671. This is not a legal requirement, but as this standard is recognised as the most thorough and is published by the UK’s highest governing body in terms of electrical installation, The Institution of Engineering and Technology, it is seen as a mandatory resource.

Generally, an accredited training course will need to be undertaken to demonstrate a full understanding of BS7671. This is something that several of the UK's registration bodies and many employers require. Ultimately, up to date BS7671 knowledge is needed for electrical work in the UK, whether employed or self-employed.

It is important to note that BS7671 is a standard that can only apply to installations - an electrician can demonstrate knowledge of this to an accrediting body, but BS7671 itself cannot apply to a person.

When was the 18th Edition issued?

The 18th edition of BS7671 was launched in July 2018, and superseded the 17th edition of the regulations, which were last updated in 2015, in January 2019. As of now, they are the standard for electrical installation in the United Kingdom.

What are the key differences between the 18th and 17th Editions?

BS7671 is updated in an iterative manner, and indeed, individual editions often seen updates within their lifetime. Generally, it’s technical advancements that drive the calls for a new edition, and we see this in part with the 18th edition and its inclusion of arc fault detection devices (AFDDs). There are many changes between the 17th and 18th editions, which would be beyond the scope of this article. However, it’s important to be aware of the major changes, which we’re going to go through here.

Arc Fault Detection Devices

AFDDs are one of the most discussed additions to the regulations, and they have been added as a recommendation to Chapter 42. These circuit breaker devices use a microprocessor to detect an electric arc in the circuit, which could pose a significant fire risk. The regulations recommend the installation of one of these devices in consumer units and at distribution boards. Such devices are still relatively new to the British market, but have been the standard in the US and Canada for several years now.

RCD Protection

RCDs are potentially lifesaving devices designed to protect users and installers from electric shock, and the 18th edition recommends increasing use of them where they were previously deemed necessary. In previous additions, these devices were recommended for installation on sockets up to 20A, but in the new regulations, <30mA RCDs should be fitted on all sockets up to 32A unless a thorough risk assessment is carried out that finds the fitment unnecessary.

Energy Efficiency

Appendix 17 is a new addition to the 18th edition regulations, and it deals with energy efficiency. This is something that regulations for numerous industries is increasingly including. As we move to have more efficient lives, and are encouraged to use less and less electricity, naturally there will be a requirement to make circuits themselves as efficient as possible. In Appendix 17, recommendations are made in terms of circuit designs and install.

Overvoltage Protection

Surge protection has been an important feature in the previous edition regulations, but the 18th Edition also brings with it a requirement to consider overvoltage protection. The guidance insists that a risk assessment is carried out to determine if this is required, with a variety of factors playing into this. Where there would be significant injury or loss of life, or where public services may be interrupted, overvoltage protection should be installed. If a risk assessment is not carried out for whatever reason, then again, overvoltage protection is a requirement.

Metal Cable Supports

Regulations previously stated that wiring found in fire escape routes should be supported by metal clips to protect against collapse in the event of a fire. This has now been revised, and the regulations suggest that all wiring installations will need support going forward, with an adequate number being constructed for metal.

Additional Scope

Finally, the 18th Edition wiring regulations also has a slightly wider scope than previously. It now includes a section on electrical shore connections for inland navigation vessels.

Further training in BS7671:2018

Electrical installers will naturally be considering the impact the new regulations will have on their processes and business. Additional equipment is clearly going to be high up the list, with metal support clips and AFDDs likely to be an additional requirement for many stocks, but additional time for installation is also going to be an important consideration. On top of this, training is a recommendation to ensure that all installers have a thorough understanding of the new regulations. The 18th edition is now readily available, but training can help to contextualise the information, and many organisations and governing bodies do require this.

Here at Virtual College, we’re very pleased to be able to offer a dedicated course that will allow any electrician to complete training in the 18th Edition in their own time, and at their own pace. This can be found here. This course contains everything electricians need to know and has been co-created with The National Inspection Council for Electrical Installation Contracting. Update courses are also available for those who’ve recently completed training in the 17th Edition.

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