BS 5839-6 Explained

BS 5839-6 is the British Standard for fire detection and alarm systems in domestic properties. 

The current version, BS 5839-6:2019+A1:2020, covers new and existing homes and provides recommendations for alarm types, placement, testing and maintenance, including how interlinked alarms can be used as part of a domestic fire alarm system.

It uses two classifications. The Grade describes the alarm equipment and power supply, while the Category describes how much of the property is covered.

What Are the BS 5839-6 Alarm Grades?

BS 5839-6 uses Grades to describe the type of alarm equipment and how it is powered. The category then describes the level of detection coverage.

This means a specification such as Grade D1, Category LD2 tells you both how the alarms are powered and where detection is provided.

The main domestic grades are:

For most domestic properties, the relevant grades are commonly D1 and D2, and F1 and F2. D1 and F1 are the alarm grades that we cover at LINKD Alarms with our wireless interlinked or mains/battery powered alarms. 

Grade A and Grade C systems incorporate central control equipment and are intended for more comprehensive domestic installations, larger residential properties or commercial premises, and are less typical in an ordinary home.

BS 5839-6 Alarm Categories

The alarm category describes where fire detection is provided within a property. LD1, LD2 and LD3 are the BS 5839-6 categories, with LD1 providing the widest level of detection.

The category is separate from the alarm grade. For example, Grade D1 LD2 describes a mains-powered system with a sealed standby battery, combined with LD2 coverage throughout the property.

The appropriate category depends on the property, its layout and the level of protection required. For a more detailed explanation of LD1, LD2 and LD3, including where each category is typically used, see our guide to fire alarm categories.

What Changed in BS 5839-6:2019+A1:2020?

The 2019 edition, amended in 2020, made several changes, including the way domestic alarm grades are defined, and updated recommendations to domestic fire alarm systems.

One of the main changes was the way alarm systems are graded. Grades B and E were removed, Grade C was redefined, and Grades D and F were divided into more specific classifications. This makes an important difference when choosing alarms:

• Grade D1: Mains-powered alarms with sealed, tamper-proof standby batteries.

• Grade D2: Mains-powered alarms with user-replaceable standby batteries.

• Grade F1: Battery-powered alarms with sealed, tamper-proof batteries.

• Grade F2: Battery-powered alarms with user-replaceable batteries.

The revision also introduced clearer guidance around testing and maintenance and clarified when carbon monoxide alarms can be connected to a fire detection system.

How Does BS 5839-6 Relate to Interlinked Alarms?

BS 5839-6 covers systems where multiple alarms work together, allowing a fire detected in one part of the property to trigger connected alarms elsewhere.

For example, if a smoke alarm detects a fire downstairs, an interlinked system can sound alarms upstairs as well. This can give occupants an earlier warning, particularly when they are sleeping or are some distance from where a fire starts.

The standard's recommendations should be considered alongside the appropriate Grade and Category for the property.

How Often Should BS 5839-6 Alarms Be Tested?

Domestic fire alarm systems should be tested regularly. For systems other than Grade A, BS 5839-6 recommends testing at least monthly.

Testing should follow the manufacturer's guidance and use the test facility provided on each alarm. In an interlinked system, each alarm should be tested individually, and the test should also confirm that the other connected alarms respond correctly.

If a fault is identified, it should be investigated and corrected rather than simply left until the next scheduled test.

Regular testing is particularly important for battery-powered alarms, as it provides a simple way to confirm that the system is still operating correctly.

Which BS 5839-6 Grade Does Your Home Need?

The appropriate grade depends on factors including the type of property, whether it is owner-occupied or rented, and whether the system is being installed as part of new construction or an existing property.

BS 5839-6 provides recommendations for different types of domestic property, including owner-occupied homes, rented accommodation and HMOs. However, the British Standard is a code of practice rather than legislation, and the legal requirements can vary across the UK.

For many domestic applications, Grade D1, D2 or F1 will be the relevant options.

If you're unsure which specification applies to your property, check the relevant regulations and guidance for your location before choosing an alarm system:

• England fire alarm regulations

• Scotland fire alarm regulations

• Wales fire alarm regulations

• Northern Ireland fire alarm regulations

BS 5839-6 Alarms from LINKD 

Our domestic fire alarm range includes Grade F1 battery-powered alarms and Grade D1 mains-powered alarms with sealed backup batteries.

The relevant product standards include:

• Smoke alarms: BS EN 14604

• Heat alarms: BS 5446-2

• Carbon monoxide alarms: BS EN 50291-1

Compatible LINKD alarms can be wirelessly interlinked using radio frequency (RF) technology and are available pre-linked before dispatch, making it easier to install a connected alarm system throughout your home.

You can build your own interlinked alarm bundle in our online store to choose the smoke, heat and carbon monoxide alarms required for your property.

Contact us today if you have any questions on compliance for your specific property and requirements.

Disclaimer: This article provides general guidance on BS 5839-6 and domestic fire alarm systems in the UK. The appropriate Grade, Category and installation requirements may vary depending on the property's location, age, layout, occupancy and intended use. BS 5839-6 is a code of practice and should be considered alongside applicable legislation, Building Regulations and any relevant fire risk assessment. Always confirm the requirements for your property before purchasing or installing a fire detection system.