High-rise buildings present specific challenges that need to be considered when assessing and addressing fire risks. Multiple floors, large number of flats and occupants, and long, complex escape routes, are just some of the peculiarities that may pose challenges to fire safety. In the unfortunate event a fire accident occurs, proper evacuation strategies need to be in place to ensure that residents are alerted and evacuated in a timely manner, and to allow the fire brigade to achieve rapid containment and suppression of the fire.
The British Standard BS8629, introduced in England and Wales in November 2019, and now mandatory in Scotland also, applies to many high-rise residential buildings and identifies the critical design criteria required to achieve an effective evacuation, controlled by the fire brigade. The standard is applicable to both new and existing buildings, currently covering all residential properties over 18 meters, and it provides recommendations about the evacuation alert system comprising the evacuation alert control indicating equipment (EACIE), along with the audible and visual alarm devices, to ensure simple, consistent and intuitive operation.
The evacuation alert system should be installed where a ‘Stay Put’ policy is in force, as a standalone network, with the sole function to assist the fire brigade in the evacuation of the building. To ensure maximum reliability and system integrity, it needs to be wholly independent from the fire detection and alarm system, and from other building control systems and equipment such as lifts, gas valves, air handling systems or smoke control systems.
Achieving an evacuation system compliant with BS8629
In order to comply with BS8629 recommendations, the evacuation system must include evacuation alert control indicating equipment that can be operated by the fire and rescue services, along with audible and visual alarm devices in each apartment, providing clear evacuation signals to building occupants.
The challenge, particularly significant in the current climate, is how to install the evacuation devices in a large number of residential units, while minimising contact with, and inconvenience for, residents, complying with health and safety regulations, and keeping to project timelines and costs. The first step to achieving this is to engage suitable qualified and accredited specialists, experts in the technology and relevant British Standards, to ensure that you achieve a fully compliant system installed rapidly and efficiently.
Given the challenges and requirements outlined above, wireless evacuation technology can represent the optimal choice for the evacuation system within high-rise buildings, thanks to the ease of installation, simplified maintenance requirements and the limited disruption to ‘business as usual’. Wired evacuation systems can take weeks to install, due to the need of complex cable infrastructure, with the potential problems of project delays and cost over runs.
Conversely, wireless evacuation devices, following a survey, can be programmed offsite and installed in minutes, delivering the highest level of protection, limiting interference with building infrastructure and aesthetics, with minimal need for cabling or firestopping, and minimum disturbance to tenants and occupants. The sounders and any other wireless device can be installed inside residential units with minimum upheaval and no requirement, in most cases, to replace any existing system, which can remain active until the new system is fully tested and commissioned.
Another advantage offered by wireless evacuation technology is enhanced flexibility for the upgrade and expansion of existing systems. All buildings are constantly evolving and any change to the use or occupancy of a building can result in compliance issues, with an evacuation system that no longer complies with the repurposed space. Traditional wired systems make changes more complex by requiring new devices to be hardwired into an existing cable network. A flexible wireless infrastructure, easily expandable or modifiable, would instead easily accommodate layout alteration, in building usage and upgrades to reflect future changes in regulations.
Even if the BS8629 Standard does not state any preference for wired or wireless devices, BS8629 Section 16 is specifically dedicated to the use of Radio Evacuation Systems, as these can offer rapid and simple solutions for high-rise buildings.
The key features of the BS8629 evacuation alert system
Ease of use and intuitive functionality are placed at the core of the new standard, which is aimed at simplifying and supporting fire brigade operations in high-rise buildings. Instead of a LED display, the evacuation alert control system needs to include a series of vertically mounted manual switches, mirroring the storeys of the building, with adjacent LEDs to easily notify a fault or to indicate that the evacuation zone is switched on. It is recommended to involve the fire and rescue services in the planning and design of the system, as this needs to support fire brigade operations and be consistent with the evacuation strategy of the specific building.
While existing wireless components from Hyfire and other manufacturers are fully compatible with evacuation alert systems, the control panels themselves are highly specialised items. So far, Advanced and C-TEC have announced new product lines, both with panels housed in boxes manufactured by Gerda Security, and we can expect further entrants into the market in the future.
The integrity of the BS8629 evacuation system is fundamental, as it is assumed that the fire will already have taken hold when the operation of the evacuation system is required. This makes a wireless evacuation system an even more logical option, as cable infrastructure can often be vulnerable to fire damage, hence the requirement for circuit isolators to be installed at the point of entry and exit to a zone and prior to cable penetration into the flat. So, the less cabling in the system, the better.
Following BS8629 recommendations, in buildings with ten storeys or fewer, two simultaneous faults on an evacuation circuit should not disable the evacuation devices on more than a half of the number of storeys with flats. In 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. Nor should a fault on a flat’s evacuation device affect any other evacuation device. Wireless evacuation devices mitigate the need for short circuit isolators at the point of entry to the flat, therefore maintaining system integrity and reducing system costs and complexity.
BS8629 also prescribes regular maintenance visits to ensure proper functioning of the system. Inspection, test and servicing have to be carried out every six months by a competent person, and an annual test has to be performed on each sounder in every residential unit (for no more than ten seconds), to verify it is functioning independently from the rest of the system. With wired devices, this would require two engineers during the annual maintenance visit, one operating from the EACIE and one within the test zone, to verify the operation of the sounder. The wireless technology limits the human resource needed on site and allows one person to autonomously complete the test, activating the single evacuation device from the connected wireless interface (translator) in the same test zone.
The wireless technology can also help meet evolving standards in the fire industry. With less time needed to install a system, minimal cabling and less manpower required, it is possible to deliver improvements quickly and efficiently, at less cost.
The team here at Hyfire is committed to provide up to date information and resources to promote better fire safety. We are hosting free webinars and Q&As about the new BS8629 Standard, its recommendations and the critical design criteria. The webinars are intended to present compliance options and provide fire professionals with all the information they need to meet BS8629 requirements. To learn what BS8629 means for high-rise buildings, how the standards should be applied and how Hyfire wireless devices can help achieve BS8629 quickly and economically register your interest in via email to info@sterlingsafety.co.uk and we’ll be in touch with details of the next available session.