Being able to warn everyone of an emergency in or around a building is an important principle for any fire alarm system and needs to be carefully considered at an early stage. Awareness of the challenges of specifically alerting deaf and hard-of-hearing people of an emergency is gaining momentum, especially now that the UK’s EA (Equalities Act) and other related legislation have come into play.
At first glance, the issues may seem straight forward, as a number of solutions are now commercially available. However, on taking a more detailed look at the different scenarios that may be encountered in every-day-life there soon emerges a deeper appreciation of some of the issues that need to be considered before committing to a final solution.
When it comes to alerting deaf or hard-of-hearing people, consideration needs to be given to the number of people that are estimated to be involved. There are estimated to be almost eight million deaf or hard-of-hearing people in the UK alone, with almost 800,000 of these being categorised as having ‘severe to profound deafness’. This is a significant number of people, so any solution needs to consider this and not be a half-thought through token solution that caters for the few.
Most of the risks are encountered when a deaf or hard-of-hearing person is alone and cannot rely on others to warn them of an emergency. This risk applies to even short periods of time, as minutes or even seconds can make all the difference in an evacuation.
The risk of not hearing an audible alarm is not only an issue for people with hearing difficulties. It is also true of people with adequate hearing, who are present in noisy environments such as factories or when the intended recipient is wearing ear defenders or headphones wired to portable music devices. There are also situations where audible alarms would not be suitable, such as in operating theatres or recording studios.
Choosing the Right Solution
There are many off-the-shelf solutions that provide an alternative to the traditional audible alarm device; the most common are VADs (Visual Alarm Devices – flashing beacons) or tactile devices, such as pagers or vibrating pillows or beds.
Each of these technologies has its advantages and shortcomings and each one has to be weighed-up against the perceived risk. The start of any such decision process is usually a risk assessment and if it is an existing building this is a legal requirement in the UK under the Regulatory Reform (Fire Safety) Order. Where new buildings are concerned, building regulations along with the relevant BS & EN standards (such as BS5839-1 and BS8300) are used, along with accepted custom and practice.
Consideration when choosing a solution must be based on effectiveness and convenience. Other factors such as installation time and cost are also highly important. The fitting of VADs in the form of beacons has been considered to be ‘custom and practice’ in the fire industry for a number of decades. They offer a solution that can better mirror that of audible devices, since they are generally mounted directly to the building and do not require any reoccurring direct intervention by the intended recipient. Regular maintenance and testing would be down to the owner or operator of the building.
Up until now, the performance of beacons has been left to personal judgment by the system designer and was often based on current consumption or joule rating. However, this gave little indication to the actual performance or effectiveness of the device once installed. This has since changed, now that the co-existence period for EN 54-23 has ended (Fire alarm devices – Visual alarm devices). VADs are now a mandatory requirement within the EU, if they are used as a primary alarm for drawing attention during a fire alarm emergency. This means that a VADs performance is now specified to a defined standard that is based on a category of Wall, Ceiling or Open and a minimum coverage volume, based on an illumination of 0.4l/m2. As a result, this will make it easier to compare devices from different manufacturers, and should result in a more consistent and effective performance once installed.
The toughest challenge has been for manufacturers to achieve the increased practical coverage volume with a minimum current consumption, thus reducing the impact on control panels and wiring. This challenge has been addressed and has propelled the industry to up its game on visual device design and implementation.
The chosen location of VADs needs to be thought through carefully. Who is the intended target, and are they likely to benefit from the signal? If the signal is intended to be for a deaf or hard-of hearing person, are they likely to be on their own? Is a deaf person likely to use sanitary accommodation designated as a ‘disabled toilet’ exclusively, for example, or would they also use the regular sanitary facilities provided for others? If VADs are located wisely following a risk assessment their impact on the control panel and wiring can be minimised.
Some difficulties might arise if a building usage changes significantly, or if a number of items of furniture are moved after installation, thus causing ‘blind spots’ in the coverage. The new COP 0001 (Code of practice – Visual alarm devices used for fire alarm warning) aids the design of fire alarm systems using visual alarm devices, and aims to improve on the coverage presently achieved with existing systems.
Another issue that may need consideration is people who suffer from epilepsy, although the number of people who actually suffer from the photosensitive condition is extremely rare, being only 5 percent of people who suffer from epilepsy as a whole.The risk is further reduced to negligible levels if all beacons visible from a view point flash within the rates stated in EN 54-23, that is, below 2Hz. Research has shown that for the very rare occasions where people with photosensitive epilepsy are affected, it is usually with visually changing frequencies between 16Hz and 25Hz. Synchronisation between visible flashing beacons is also important and this can easily be achieved by using either a bespoke external trigger for cross-zone synchronisation, or an integrated solution such as Eaton’s ‘Phase synch start’ feature, built into all LX VAD products.
Getting a Good Vibe?
Portable tactile devices such as pagers are sometimes talked about as being a favourable alternative to VADs. At first glance, this may appear to be the case, particularly from the designer’s and installer’s point of view, since less consideration needs to be given to the building and room layout. Indeed, pagers can be carried from room to room, so giving constant reassurance to the user. However, there are practical difficulties with some tactile devices that should be thoroughly understood before considering them as a suitable alternative.
For example, are people fully aware of their own hearing limitations in the first place? Most of us, who are getting on in years may not like to admit that our hearing is not what it used to be, especially those, like myself, who liked to listen to loud music in their distant youth. A problem arises if a person is not aware of their own potential hearing loss, as they will not implement a personal solution to a problem that they do not perceive exists. Thus a well-designed fire alarm system with integrated VADs, signalling to all occupants of a building – whether they recognise their hearing loss or not – may be favourable.
For a tactile device such as a pager to be effective, it needs to rely on constant body contact. Missing a mobile telephone call by not ‘feeling’ the vibration is one thing, but loosing physical contact with a lifesaving pager is quite another. Loose fitting clothing or removing an item of clothing to which the device is attached is a real issue. Questions about what happens when a person using a tactile device disrobes to have a shower or bath needs to be answered. Even when people are aware of the need to use a tactile device, are they likely to take unnecessary risks when practical day-to-day situations arise that may require that they remove the device, such as in a sauna or swimming baths?
Are all users of portable tactile devices conscientious enough to be aware of the risks of not replacing a battery for example? We have all heard of cases where people have innocently removed a failing battery from a domestic smoke alarm, with very good intentions to replace it, but do not actually get around to it for several weeks. Even a short down time can have serious consequences in an emergency.
Clearly, the successful use of personal tactile devices requires a great deal of user responsibility and education as to their correct use and limitations.
A flash of Inspiration
The best approach is to use the appropriate device for a given situation having weighed up all the risks. Pagers may complement a fixed system using VADs, but it could be argued that they would not replace them. Flashing beacons are a well-established form of warning of an emergency and are familiar to designers, installers and users alike. Being fixed to the building, they are under the control of the building operator rather than the intended recipient. Ultimately, one visual alarm device can signal to all recipients within a given range, unlike a pager that is a personal signalling device.
Implementing a solution that is appropriate for the particular circumstances would better fit with the spirit of the Equalities Act; that of not treating people with disabilities ‘less favourably’ than able bodied people.
Looking carefully at the use of a building and some of the practicalities surrounding its use, should give a better understanding of the best technology to implement, for the safety and convenience of its occupants. Visual alarm devices are familiar products that are well established in the fire industry, and the new EN 54-23 standard along with the COP 0001 Code of Practice, will further enhance the use of visual alarm devices in situations where alternatives are not suitable or practical.
For further information, go to www.cooperfulleon.com