The challenges and solutions

08 April 2015

Being able to warn everyone of an emergency situation in or around a building is an important principle of any fire alarm system and needs to be carefully considered at an early stage of any project. 

Awareness of the challenges of alerting deaf and hard of hearing people in an emergency is gaining momentum, especially now that the Equalities Act 1 and other related legislation have come into play.

At first glance, the issues may seem straightforward as an array of solutions are available for ready implementation. 

However, a more detailed look at the different scenarios that may be encountered in everyday life shows a deeper appreciation of some of the issues that need to be considered before committing to a solution.   

When it comes to alerting deaf or hard of hearing people, consideration needs to be made to the numbers of people that are involved. 

There are estimated to be around 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’ {source: Action on Hearing Loss - formally RNID}2. 

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 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 in noisy environments such as factories or night clubs, or when the intended recipient is wearing ear defenders or headphones. 

There are also situations where audible alarms would not be suitable, such as operating theatres or recording studios.


A question of risk

Choosing a suitable solution for any situation will be governed by many things. 

The start of any such decision process is usually a risk assessment and, if it is an existing building, this is a legal requirement under UK fire safety legislation 3. 

Where new buildings are concerned, building regulations along with the relevant BS & EN standards (such as BS 5839-1 2013, BS 8300 etc.) are used along with accepted practice.

The factors that should be considered when choosing a suitable solution need to be based on the perceived risks and the relative effectiveness, and possible convenience, to the person which the solution is intended. 

Other factors such as installation time and cost are also important. 

An assessment of the hazards and the risk to which people are exposed should identify any deficiencies and clearly indicate the means required to reduce the risk to at least a tolerable level. 

This would include providing alternative means of alerting people with hearing difficulties of an emergency.


Who’s your buddy?

There are many ways to approach alerting deaf and hard-of-hearing people in an emergency. 

One possible way could be to simply ensure that one or more people are nominated to assist the person with hearing difficulties. This is known as a ‘buddy system’. 

This would mean remaining close to the designated person with hearing difficulties during most or all of their presence within or around a building. 

While this solution may seem straight forward and cost effective at first glance, there are implications. In a reasonably controlled environment, such as an office, buddy systems can work well. We also need to be sure that the ‘buddy’ in charge is of a suitable temperament and is adequately trained. 

A great deal of patience and self-awareness may be required during an emergency.  Additional difficulties may arise if there is no control of people entering or leaving a building or adequately assessing their specific needs. 

There is no right or wrong here but all the aspects would need to be weighed up as part of the risk assessment.


A flash of inspiration

There are many off-the-shelf solutions that provide an alternative to the traditional audible alarm device; the most common being visual alarm devices (VADs) or tactile devices such as pagers or vibrating pads for pillows and mattresses. 

Each of these technologies has its advantages and shortcomings and each one has to be weighed up against the perceived risk. 

The fitting of VADs in the form of flashing beacons offers 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 & testing would be down to the owner or operator of the building.

Up until now, the effectiveness of beacons has been left to personal judgments made by the system designer and was often based on power consumption or joule rating. 

However, this gave little indication to the actual performance or effectiveness of the device once installed. 

This has changed now that the co-existence period for EN 54-23 has ended (Fire Alarm Devices – Visual Alarm Devices)6 meaning that where VADs are fitted for the primary purpose of alerting people to an emergency they must, by law9, be certificated in conformity with this standard. 

Beacon performance is now specified to a defined standard which is based on three categories of either wall, ceiling or open and a minimum ‘coverage volume’. The coverage volume is based on a Minimum Required Illumination (MRI) of 0.4 l/m2. 

In summary, this will make it easier to compare devices from different manufacturers, and should result in a more consistent and effective performance once installed.

The challenge for manufacturers has been to achieve increased practical coverage volume with a minimum impact on current consumption to help reduce any possible impact on control panels and wiring. 

The industry appears to be addressing this challenge with the introduction of a number of new and innovative solutions.

The chosen location of a VAD needs to be thoroughly thought through. Who is the intended target and are they likely to benefit from the signal? If the signal is intended for a deaf or hard-of hearing person, are they likely to be on their own? 

Where deaf people will be mixing with hearing people and there is a robust procedure for ensuring the premises has been cleared, no visual warning might be appropriate. 

Whereas in situations where a deaf person might be alone or there could be a long delay before they become aware of an alarm, VADs might be appropriate. 

A typical example is sanitary accommodation (e.g. bathrooms and toilets). Indeed, ADM10 recommends visual alarms in all sanitary accommodation. If VADs are chosen and 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, causing ‘blind spots’ in the coverage. 

The new COP 0001 (Code of Practice - Visual Alarm Devices Used for Fire Alarm Warning)7  aids the design of fire alarm systems using VADs and aims to help improve on the effective coverage achieved with existing systems.

Another issue that also requires consideration is people who suffer from photosensitive epilepsy, although the number of people who actually suffer from this condition is extremely rare (only five per cent of people who suffer from epilepsy as a whole). 

The risk is further reduced to almost negligible levels if all beacons visible from a viewpoint flash within the rates stated in EN 54-23 i.e. below 2 Hz. 

Research has shown that for the very rare occasions where people with photosensitive epilepsy are affected, it is usually with visually changing frequencies between 16 25 Hz8, well above the frequencies of a VAD. 

If required, flash synchronisation between visible VADs can be achieved by using either a bespoke external trigger for cross-zone synchronisation, or an integrated solution such as a self-start synchronisation feature available from some manufactures. 

The introduction of specific VAD product standards and installation codes of practice does offer the system designer a more level playing field when it comes to comparing and choosing a suitable device based on specific requirements. 

However, although flashing beacons are a familiar technology that has been used to complement audible devices for many years, the way they should be used has changed and so this demands a rethink and a greater understanding of the intended use and coverage required. 


Getting a good vibe

Portable tactile devices such as pagers can be a suitable alternative to VADs in specific circumstances. From the designers and installers point of view, they may be easier to design and install since less consideration may need to be given to the building and room layout. 

Pagers or vibrating devices can also be more easily swapped out in the event of a failure, without the need for closing off an area of the building while maintenance personnel fix the problem. Maintenance costs and down time can therefore be minimised. 

Pagers can be carried from room to room, giving constant reassurance to the user. 

However, as with other solutions, there can be practical difficulties that should be carefully considered before considering tactile devices as a suitable alternative. 

For example, are people fully aware of their own hearing limitations in the first place? Most of us may not like to admit that our hearing is not what it used to be. A problem arises that, if a person is not aware of their own potential hearing loss, they will not implement a personal solution to a problem that they do not perceive exists. 

Tactile devices, by definition, generally need to rely on constant body contact. Missing a mobile telephone call by not ‘feeling’ the vibration is one thing, but losing physical contact with a lifesaving pager is quite another. 

Loose fitting clothing or removing an item of clothing to which the device is attached could be an issue. Disrobing to have a shower, visit a sauna or swim could result in loss of contact with the device. Are all users of portable tactile devices conscientious enough to be aware of the risks of not replacing a battery for example?  Even a short down time can have serious consequences in an emergency. 

The key to successful use of personal tactile devices is education and training related to their correct use and a good measure of personal responsibility of the user too.


Best way forward

The best approach is to use the appropriate device for a given situation having weighed up all the risks. There isn’t a right or wrong solution, only a set of complementary solutions that are on offer to the designer or specifier. 

Implementing a solution that is based on a risk assessment and has been carefully considered as appropriate for the particular circumstances should fit well within the spirit of the Equalities Act. 

The spirit of the act is not treating people with physical disabilities less favourably than able bodied people.

Carefully looking at the function of a building and some of the practicalities surrounding its use, along with the needs and practicalities encompassing the intended recipient, should give a better understanding of the best solutions to implement for the safety & convenience of all the intended recipients within a building. 


By Steve Martin, FIA Fire Detection and Alarm Council Member

References:

1 EA (Equalities Act) 2010

2 Action on Hearing Loss (formally RNID - Royal National Institute for Deaf People)

3 Regulatory Reform (Fire Safety) Order 2005 (England and Wales), Fire (Scotland) Act 2005 and Fire & Rescue Services (Northern Ireland) Order 2006

4 BS 5839-1:2002+A2:2008 

5 BS 8300:2009+A1:2010 Design of buildings and their approaches to meet the needs of disabled people – Code of practice

6 EN 54-23:2010 Fire detection & fire alarm systems – Fire alarm devices – Visual alarm devices

7 COP 0001: Issue 1.0 - Code of Practice - Visual Alarm Devices Used For Fire

8 British Epilepsy Association publication ‘Photosensitive epilepsy’ 2010

9 The Construction Products Regulations 2013

10 Approved Document M Access to and use of buildings (England and Wales) guide to complying with Building regulations