The new amended Part B of the Building Regulations came into force in the UK on 1 December 2022 and comprises some important changes concerning evacuation of buildings, including the new requirement for evacuation alert systems to be fitted in new, high-rise residential buildings over 18m in England – this feature explains more.
The updated Approved Document B of the Building Regulations is set to bring clarity and improved fire safety to high-rise residential buildings following the most serious fire tragedy the UK has ever seen in recent history: Grenfell Tower. The Grenfell Inquiry found that Building Regulations were lacking in certain areas while the evacuation of the building was hindered by a number of decisions and features of the building itself. One of the key flaws that led to the tragedy at Grenfell was the failure of the evacuation plan, there were no plans in place for evacuating Grenfell Tower should the need arise. Despite lessons that should have been learnt from previous fires in high-rise residential blocks, the traditional ‘stay put’ policy was adopted despite the building’s compartmentation being compromised by unsuitable cladding – and there was no Plan B. With no fire drills, limited instruction and no effective communication between rescue services and residents, the devastating outcome was all but inevitable.
The Inquiry highlighted that the ‘stay put’ policy needed to have a Plan B: the fire and rescue service had to have a means of doing something beyond knocking on doors to alert people to leave the building in an emergency. The Inquiry recommendations included that all high-rise residential buildings (both those already in existence and those built in the future) be equipped with facilities for use by the fire and rescue service enabling them to send an evacuation signal to the whole or a selected part of the building by means of sounders or similar devices. The response from industry experts and the fire and rescue service was to create BS 8629, a code of practice for an evacuation alert system for use by the fire and rescue service.
Industry standards move much faster than Government regulations and so the British Standards Institution (BSI) was able to act quickly and published the new BS 8629 code of practice in 2019. This code of practice is cited in the updated Part B of the Building Regulations which requires evacuation alert systems to be installed in all new-build residential blocks over 18m in England. In order to comply with the Building Regulations, the evacuation alert system needs to adhere to BS 8629. This should give residents in high-rise residential buildings reassurance that if the fire and rescue service needs to tell them to leave the building, the instruction will be communicated clearly and safely, whether by an external alarm or flashing lights.
Evacuation alert systems
An evacuation alert system is vital to help the fire and rescue service inform residents of a change in evacuation strategy during an incident, providing an additional tool to use on the ground, alongside existing methods of evacuation, improving safety for residents. The system recommended by BS 8629, for which Advanced and other companies have developed a bespoke solution, is relatively straightforward. With a BS 8629 system, evacuation is controlled and targeted floor by floor according to the magnitude and location of the fire, enabling the fire and rescue service’s main commander to evacuate specific areas of the building effectively. Evacuation alert systems can help ensure staircases are not overwhelmed, control the evacuation and send firefighters into the building where necessary. The guidance states that the evacuation alert control system should be installed where a ‘stay put’ policy is in force, so that it can be used to facilitate a timely and ordered evacuation for all residents.
Evacuation systems must include evacuation alert control and indicating equipment that can be operated easily by the fire and rescue service. A series of vertically mounted manual switches typically mirror each floor of the building with each switch incorporating LED technology to indicate whether the evacuation zone is active and to notify of any faults. In addition, audio and/or visual alarm devices are located in each apartment, providing clear evacuation signals to building occupants. An evacuation alert system must also be standalone, with its only function being to assist the fire and rescue service in the evacuation of the building. The system cannot be integrated with any element of a fire system to fully comply with the standard. Furthermore, access to an evacuation alert system should be via a patented key only – exclusive to the fire and rescue service and it is vital that the evacuation alert system is clearly marked ‘For Fire and Rescue Service Use Only’.
Advanced was at the forefront of the development of a BS 8629 solution and first to market with an evacuation alert system. The EvacGo Evacuation Alert System is designed as an easy way to meet BS 8629 and offers peace of mind to those responsible for a building that, by choosing this system, they are complying with the new Building Regulations. In addition, Advanced is currently one of a handful of manufacturers to offer an evacuation alert system housed within a box specially designed by Gerda Security to meet stringent anti-tamper standards.
The BS 8629 standard also recommends that the local fire and rescue service should play an active role in the operation, and operational specification of every new system. This helps to guarantee it is fit for purpose, as well as ensuring that personnel are familiar with it in readiness for an emergency situation.
An evacuation system will only be employed when a fire is well underway, so the integrity of any BS 8629-compliant evacuation system is a key factor in its design and specification. It is essential that critical cable infrastructure is protected, and circuit isolators are installed at the entry and exit points to each zone, as well as prior to cable entry into each flat. The rules depend on the height of the structure. For buildings with fewer than ten storeys, two simultaneous faults on a single circuit should not disable the evacuation devices on more than half the number of storeys with flats. For buildings with ten storeys or more, two simultaneous faults on an evacuation circuit should not disable the evacuation devices on more than a third of the number of storeys with flats. A fault on a single flat’s evacuation device should not be permitted to affect any other device elsewhere on the system.
To ensure the readiness and reliability of the system, regular maintenance and testing are critical and a qualified engineer should carry out a full inspection every six months. In addition, annual testing must be completed on each sounder to verify its ability to function autonomously from the rest of the system.
It is also essential to have a backup power supply for the evacuation alert system in the event of a mains power failure, and it must comply with BS EN 54-4 requirements. Standby batteries must back up the system for at least 72 hours and 30 mins while all evacuation alert zones remain active. If an onsite generator is present and someone is responsible for it, standby time can be reduced to 24 hours and 30 minutes.
The biggest challenge until now has been that these evacuation alert systems have not been mandated, despite the Grenfell Inquiry recommendations. The amended Part B of the Building Regulations changes this for some buildings. However, at Advanced we feel the amendments to the Building Regulations do not go far enough. We think the installation of evacuation alert systems should be mandated following a risk-based approach since the risk for occupants might be just as real at 10m as it is at 11m or 18m.
Amended Part B is designed to meet recommendations from Phase One of the Grenfell Tower Inquiry. However, since the Grenfell Tower Inquiry also recommends evacuation alert systems for high-rise residential buildings ‘already in existence’,1 further regulation may follow.
Now is the time to ensure that you are up to date on the new Building Regulations since the changes have big implications for the people designing and installing these systems. Advanced offers a free FIA-certified CPD to help people who are designing and installing these systems or working out whether they need to be included. The CPD explains more about BS 8629, how evacuation alert systems differ from fire detection and alarm systems, and how they are installed differently. A tall building’s electrical design should now have an evacuation alert system built into it, along with other solutions called for within the Building Regulations. Advanced would like to see evacuation alert systems being included in the early phases of the design.
By including an evacuation alert system from the design stage of residential buildings over 18m, not only will Building Regulations be met but the system will work seamlessly within the building, will assist the fire and rescue service and help make the building safer for its residents in the event of a fire.
Advanced’s handy pocket guide to BS 8629 has been produced to help people understand what they need to do to comply and is available to downloaded at https://bit.ly/3DFtldN
For more information, go to www.advancedco.com
1. Grenfell Tower Inquiry Phase 1 Report, Vol 4, June 2017, Page 777 section 33.22d. http://bit.ly/3G9AfZY