anosognosia

Grenfell Inquiry Recommendations (3) – Fire Alarms !!

Previous Posts In This New Series …

2019-10-31:  Grenfell Tower Fire Inquiry’s Phase 1 Report – Information

2019-11-11:  Grenfell Inquiry Recommendations (1) – Vulnerable People ?

2019-12-21:  Grenfell Inquiry Recommendations (2) – Fire Emergency Plans !

2020-03-23:  The Grenfell Fire Inquiry’s Phase 1 Recommendations (Part V in Volume 4 of the Phase 1 Report), were published on 30 October 2019.  The initial issues covered in those Recommendations are fragmentary, lack depth and coherence … and in the case of Fire Alarms, with just one indirect reference to them in Paragraph #33.22 … they are in serious error.

Colour image showing the Volume 4 Cover Page of the Grenfell Tower Inquiry Phase 1 Report.  The Phase 1 Recommendations are contained in Chapter #33, on Pages 771-780.  Click to enlarge.

[ Paragraph #33.22 ]  There were no plans in place for evacuating Grenfell Tower should the need arise.  I therefore recommend:

d. 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 services enabling them to send an evacuation signal to the whole or a selected part of the building by means of sounders or similar devices ;

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FUNDAMENTALS OF A SOLUTION

1.  A Fire Alarm (more precisely from here on, a Fire Detection & Warning System) is a critical safety feature in all buildings … ALL BUILDINGS … from the smallest and most simple, to the biggest and most complex … no exceptions !!

In order to survive in a fire emergency, Vulnerable Building Users need more time to react, and evacuate, than other occupants/users.  The valuable time provided by early, accurate and precise detection is the only way to effectively facilitate this.  The ‘Required Time’ to prepare for evacuation depends on many factors, e.g. building complexity, familiarity of users with evacuation routes, range and severity of user activity limitations, etc.

It follows, therefore, that if building occupants/users have to wait 15, or 20, or 30 minutes before firefighters arrive at the fire scene (Full Response Time*) and ‘an evacuation signal to the whole or a selected part of the building’ is only then sent by those firefighters … all of that valuable evacuation time for vulnerable building users has been lost.  This is ridiculous, and makes no sense whatsoever.  This Recommendation must be rejected out of hand, and ignored !

[ *Full Response Time: The time interval from the receipt of an emergency communication at the primary public safety answering point (#PSAP) to when emergency response units are initiating action or intervening to control a fire incident. ]

Colour photograph showing the Single, Narrow Staircase (1.040 metres in width between a handrail on one side of the staircase and a bare wall on the other side) in London’s Grenfell Residential Tower.  This staircase, which was inadequately protected from fire, heat and smoke, was not wide enough to facilitate the ‘contraflow’ circulation of firefighters entering, while occupants evacuated at the same time.  Without a Fire Alarm in the building, occupants could not have known that a serious Fire Emergency was in progress … especially Vulnerable Building Users accommodated high up in the Tower … and they remained in place (‘stayed put’).  Once firefighters arrived at the scene, occupant evacuation using this staircase became impossible or extremely difficult.  Click to enlarge.

Important Note:  In Chapter #34: ‘Looking Ahead to Phase 2’ of Moore-Bick’s Phase 1 Report, Volume 4 … Paragraph #34.14 states …

A question was raised about the width of the stairs, given that they provided the sole means of access to the upper floors of the tower for firefighters as well as the sole means of escape for the occupants.  However, the stairs appear to have complied with requirements of the legislation in force at the time of their construction and the expert evidence supports the conclusion that they had sufficient capacity to enable all the occupants of the building to escape within a reasonable time.  This aspect of the building will not, therefore, be the subject of further investigation in Phase 2.’

Astounding !  Absurd !!  FUBAR !!!

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All Fire Emergency Warning Systems must be designed to accommodate People with Hearing Impairments.  Audible and visual warning devices must be provided together, as a single combined unit.  This is particularly important in noisy and isolated building spaces, e.g. bathrooms, small meeting rooms.  Vibrating devices, such as pagers or mobile phones, can be integrated into a building’s fire emergency warning system in order to provide any individual with a tactile emergency alert.

Colour photograph showing a single combined visual-audible Fire Emergency Warning Device.  Click to enlarge.

Important Note:  Audible sounders, on their own, are never a sufficient Fire Emergency Warning !

2.  The Purpose of a Fire Emergency Warning System is to provoke calm, efficient and adaptable evacuation movement by ALL building users/occupants at the earliest possible stage in a fire incident, without causing user confusion, disorientation or panic. In all building types, therefore, a reliable, informative and accessible fire emergency warning system must be installed, and such a system must always have a fire protected electrical supply.

Colour photograph showing the movement of building occupants and users.  The purpose of a Fire Emergency Warning System is to provoke calm, efficient and adaptable evacuation movement by ALL building occupants at the earliest possible stage in a fire incident, without causing user confusion, disorientation or panic.  During a Fire Emergency, STANDARD MOVEMENT TIMES DO NOT EXIST.  Click to enlarge.

3.  To provoke a Calm Response from Building Users … the output from Fire Emergency Warning Devices, e.g. light, sound and messages, must be adapted to the local context of people and building surroundings.

Fire Emergency Audible Warnings … A sufficient number of low-output audible sounders, i.e. between 60-80 dB, must be specified for effectiveness.  Small numbers of sounders with high output (in order to reduce costs) should never be specified, as this can lead to confusion, disorientation and panic attacks among some building users/occupants.  The output of sounders must be adapted to suit interior surroundings, e.g. in small spaces with hard surfaces a lower sound output will be adequate.

Colour image.  The output from Fire Emergency Audible Sounders must be between 60-80 dB.

Important Note:  When they are asleep, hearing-able children (around ten years of age and under) … and hearing-able older people (around 65 years of age and over) are more difficult to wake and rouse sufficiently for evacuation when alerted by an audible signal alone.

Fire Emergency Visual Warnings … Light strobes/beacons must be clearly visible.  To reinforce #1 above … light strobes/beacons must be placed in wash rooms and in other locations within buildings where people may be alone ; they must also be placed in noisy environments.

A sufficient number of low-output strobes/beacons must be specified for effectiveness.  Small numbers of strobes/beacons with high output (in order to reduce costs) should never be specified, as these produce a glare which may cause confusion, disorientation and panic attacks among some building users/occupants.  The light output of strobes/beacons must be adapted to suit interior surroundings, e.g. in dark rooms.

For light strobes/beacons, a slow rate of flash is important, i.e. no faster than once every two or three seconds, in order to encourage a calm response from building users/occupants and to avoid photosensitivity seizures.  Most importantly, the flash of one strobe/beacon must be synchronized with the flashes of all other light strobes/beacons in view.

Colour video clip (.gif).  The output from Fire Emergency Visual Strobes / Beacons must be no faster than one flash every two or three seconds.  The flash rate shown above is too fast !   Click to run video clip.

Fire Emergency Voice Message Warnings … Are essential to improve Warning Credibility.  In other words, building users are far less likely to sit around wondering, waiting to see whether this is a ‘real’ fire emergency, a false alarm, a practice evacuation, or an electrical error.  Verbal or voice messages must be short and contain appropriate warning information which is easily assimilated.  The speaker should be distinct and easy to understand.  Live messaging during a fire emergency is preferred over pre-recorded, standard messages.  In today’s multi-cultural social environment, messages must be transmitted in at least two to three different languages, as appropriate.

Fire Emergency Directional Warnings … Combination sounder, visible strobe/beacon, and voice messaging Fire Emergency Warning Devices are now a mainstream technology, are readily available, and are being specified in new and existing buildings.

Colour image showing a combination Fire Emergency Directional Audible Sounder, with Voice Messaging capability.  Click to enlarge.

Audible directional signalling must be installed when dealing with difficult building configurations, e.g. in large open office layouts/spaces with minimal signage … where building users/occupants are unfamiliar with their surroundings in modern shopping centres/malls and other complex building types … or visibility of high-level signage may be reduced because of smoke logging.

Directional sounders, which guide building users during a Fire Evacuation towards Exits, Areas of Rescue Assistance and Lift/Elevator Lobbies, must be positioned at carefully chosen, suitable locations.  Once reached, a directional sounder must also have a voice messaging capability in order to inform people about the next phase of evacuation.

4.  Fire Emergency Warning Systems must be Accessible (for People with Activity Limitations), i.e. capable of transmitting a warning in many formats in order to ensure that all users/occupants perceive and act upon the warning in a calm manner and, thereafter, that effective evacuation movement commences without delay. Warning Credibility improves in direct relation to the type and number of different warning formats.

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As well as indirectly referring to Fire Detection and Warning Systems, Paragraph #33.22 in Moore-Bick’s Phase 1 Recommendations has some other things to say about Evacuation.  So this is an opportune moment to discuss some practical and human issues concerning Fire Emergency Evacuation … and, straight away, to deal with an unexpected consequence arising from the current CoronaVirus/CoVID-19 Emergency …

CORONAVIRUS / CoVID-19 EMERGENCY

There have been widely reported instances, in many countries, of panic buying in shops because of the 2020 CoronaVirus/CoVID-19 Emergency … but the photograph below illustrates an example of a panic reaction by building management.  This appears to be a crime scene … the yellow and black tape is so dramatic.  In a real Fire Emergency, many building users/occupants will be reluctant to use this final fire exit ; they will not have the time to read the small print on a notice ; they will attempt to re-trace their path of evacuation and find another exit.

Colour photographs showing how, as a panic reaction to the 2020 CoronaVirus/CoVID-19 Emergency, a Final Fire Exit has been blocked off from normal, everyday use.  Click to enlarge.

This panic reaction by building management IS a serious impediment to Fire Evacuation !

Whatever the Motives of Building Management …

  • in countries which have Fire Codes / Regulations, this action is illegal ;   and
  • in these days, when a wide range of ‘smart’ technologies is readily available … this action is inexcusable.

SOME PRACTICAL FIRE EVACUATION ISSUES

A Skill is the ability of a person, resulting from competent training and regular practice, to carry out complex, well-organized patterns of behaviour efficiently and adaptively, in order to achieve some end or goal.  All building occupants/users must be skilled for evacuation to an external ‘place of safety’, which is at a safe and remote distance from the fire building.  Practice fire evacuations must be carried out sufficiently often to equip building users, particularly vulnerable users, with this skill, i.e. at least once every six months ; in complex building types, practices should be carried out more often.  Prior notification to occupants/users, and regular scheduling of practice evacuations should be avoided.

Familiarity with Fire Evacuation Routes will be fostered and greatly improved by means of normal, everyday use by occupants/users.  This is an important task for pro-active Building Management in existing buildings … and an important aspect of new building design for Architects and Fire Engineers.

While the transmission of fire emergency warnings in many formats will increase Warning Credibility, close observation of past tragic ‘real’ fire events, e.g. the WTC 9-11 Attacks in New York City, shows that initiation of evacuation and the actual process of evacuation itself can be problematic.  An interesting, easily assimilated and user-targeted skills programme of training should incorporate practical solutions to deal with the following typical problems:

  1. Fire Emergency Preparedness: Irregular attendance of building occupants/users at fire prevention and safety training sessions, and participation in practice fire evacuations. Users not being familiar with a building’s fire emergency management plan and not knowing who is in charge … not using a building’s fire evacuation route(s), particularly staircases, during practices … or having no information about where to assemble after evacuating … or, once at a place of safety, not having any head count or identification process ;
  2. Delaying Activities Inside The Fire Building: Once building occupants/users decide to evacuate, but before moving to evacuate, they gather personal effects … seek out friends/co-workers … search for others … make phone calls/send tweets … finish tasks/turn off computers … wait around for instructions … change shoes … and try to obtain permission to leave ;
  3. Delaying Activities Outside The Fire Building: Once outside the building’s final fire exit, but before moving directly to a place of safety, building occupants/users stop to see what is happening … look for friends/co-workers … look for a phone … do not know where to go … or, within the ‘danger zone’ of the fire building, stop to receive medical attention.

It may seem obvious that Fire Evacuation Routes must also be Accessible (for People with Activity Limitations), which also makes routes much safer for every other building user … and sufficiently wide to accommodate Contraflow (emergency access by firefighters or rescue teams into a building and towards a real fire, while building users are still moving away from the fire and evacuating the building) … a harsh lesson learned from the 2001 WTC 9-11 Attacks and the 2017 Grenfell Tower Fire. Since they are new, strange and unusual for many building designers, and most fire engineers … these aspects of building performance are overlooked in nearly every building.

Practice Evacuations should include exercise of the buddy system ; fire safety fittings, e.g. portable fire extinguishers ; and fire evacuation devices intended for use by people with activity limitations which will require more intensive training.

Colour image showing a range of personal Facilitation / Mobility Aids.  People with Activity Limitations must be allowed, and positively encouraged, to keep these Aids during practice and real fire evacuations.  Prior meaningful consultation (see below) is essential.  Click to enlarge.

Important Note:  During fire emergencies, People with Activity Limitations must be permitted to keep possession of their own personal Facilitation / Mobility Aids.

SOME HUMAN FIRE EVACUATION ISSUES

The actual people who use and occupy buildings are individuals.  They are different from each other, and they each have a different range of abilities (in relation to self-protection, independent evacuation to an external place of safety remote from a fire building, and active participation in a building’s fire emergency management plan), behaviour and manner of perceiving their surroundings.  Two apparently similar people will also show variations in how they react to and behave in any specific situation, particularly a fire emergency.

Ability / Disability is a Continuum – a gentle gradient on which every person functions and acts at different levels due to personal and environmental, i.e. external, factors.

In situations of severe stress, e.g. during a fire emergency in a building, where there is a lack of preparedness for such an event, a lack of familiarity with evacuation routes, lack of reliable evacuation information, lack of competent leadership and clear direction, and the presence of smoke, user/occupant confusion, disorientation and panic will occur.  Standard evacuation movement times will also be non-existent.  In addition, people with activity limitations must then deal with many physical barriers which routinely impede their evacuation from buildings, e.g. fire resisting doorsets which are difficult to open, steps along evacuation routes and at final fire exits.

In the case of people with a mental or cognitive impairment, there is a particular need to encourage, foster and regularly practice the adaptive thinking which will be necessary during evacuation a real fire incident.

People with respiratory health conditions will not be able to enter or pass through smoke.  People with visual impairments will require continuous, linked tactile and/or voice information during the whole process of fire evacuation.  People with psychological impairments, i.e. vertigo and agoraphobia, will be unable to use fire evacuation staircases with glass walls in high-rise buildings.  Because of the stigma still associated with disability in many countries, some users/occupants who will need assistance during a fire emergency will be reluctant to self-identify beforehand.  Other people may not even be able to recognize that they have an activity limitation or a health condition.

Meaningful Consultation with a person known to occupy or use a building, for the purposes of receiving his/her active co-operation and informed consent (involving a personal representative, if necessary), is an essential component of adequate pre-planning and preparation for a fire emergency.

Building Designers, Fire Engineers and Firefighters should be aware of the following human conditions:

Agoraphobia: A fear of open spaces.

Commentary: Agoraphobia is one of the most commonly cited phobic disorders of people seeking psychiatric or psychological treatment. It has a variety of manifestations, e.g. a deep fear of leaving a building, or of being caught alone in some public place. When placed in threatening situations, agoraphobics may experience a panic attack.

Anosognosia: A neurological disorder marked by the inability of a person to recognize that he/she has an activity limitation or a health condition.

Dementia: Any degenerative loss of intellectual capacity, to the extent that normal and occupational activities can no longer be carried out.

Panic: A sudden overwhelming feeling of anxiety, which may be of momentary or prolonged duration.

Panic Attack: A momentary period of intense fear or discomfort, accompanied by various symptoms which may include shortness of breath, dizziness, palpitations, trembling, sweating, nausea, and often a fear by a person that he/she is going mad.

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People with Activity Limitations (2001 WHO ICF) ?

2009-05-12:  Or … in French: Personnes à Performances Réduites … a term which should be used much more often !

 

For many decades, the language of ‘disability’ has been all over the place, to put it mildly … others might suggest, however, that it lacks coherence, and is fragmented and chaotic !   As a result, it has been difficult to make any sort of solid progress on harmonization … at a technical level … in Europe.

 

Adopted on the 22nd May 2001, the World Health Organization’s International Classification of Functioning, Disability & Health (ICF), changed that situation for the better.  It is important to emphasise that the ICF is a classification of ‘Health’ … not of ‘Disability’.

 

 

People with Activity Limitations (English) /

Personnes à Performances Réduites (French):

Those people, of all ages, who are unable to perform, independently and without aid, basic human activities or tasks – because of a health condition or physical/mental/cognitive/psychological impairment of a permanent or temporary nature.

 

This term includes …

 

         wheelchair users ;

         people who experience difficulty in walking, with or without aid, e.g. stick, crutch, calliper or walking frame ;

         frail, older people ;

         the very young (people under the age of 5 years) ;

         people who suffer from arthritis, asthma, or a heart condition ;

         the visually and/or hearing impaired ;

         people who have a cognitive impairment disorder, including dementia, amnesia, brain injury, or delirium ;

         women in the later stages of pregnancy ;

         people impaired following the use of alcohol, other ‘social’ drugs, e.g. cocaine and heroin, and some medicines, e.g. psychotropic drugs ;

         people who suffer any partial or complete loss of language related abilities, i.e. aphasia ;

         people impaired following exposure to environmental pollution and/or irresponsible human activity ;

 

and

 

         people who experience a panic attack in a fire situation or other emergency ;

         people, including firefighters, who suffer incapacitation as a result of exposure, during a fire, to poisonous or toxic substances, and/or elevated temperatures.

 

 

Anosognosia:

A neurological disorder marked by the inability of a person to recognize that he/she has an activity limitation or a health condition.

 

 

 

What is the big deal here ?

 

Because of the stigma which still attaches to ‘disability’ … and because some people are unable to recognise that they have an activity limitation or a health condition … depending on self-declaration, alone, for the purposes of developing suitable Fire Safety Management Procedures in a building (of any type) is a recipe for certain failure of those procedures.

 

And … of very direct relevance to design practice generally … compare the weak and inadequate definition of people with disabilities in Part M4 of the Irish Building Regulations (there is no reason to suspect that there will be an earth shattering improvement to this definition in the Revised Technical Guidance Document M … whenever it eventually sees the light of day !) … with the definition of disability in Irish Equality Legislation.

 

Chalk and Cheese !   Or … from the ridiculous to the sublime !   Check it out for yourself.

 

The consequence of this remarkable difference in definitions for anyone involved in the design and/or construction of a building is that … while they might very well be satisfying the Functional Requirements of Parts M and B in the Building Regulations … they will, more than likely, be still leaving the owner and the person who controls or manages the new building open to a complaint under our Equality Legislation.

 

In the case of Workplaces … truly brave is the person who will design a ‘place of work’ just to meet the minimal performance requirements of Building Regulations !

 

 

As a Rule of Thumb, therefore … architects, engineers, facility managers, construction organizations, etc, etc … should become more comfortable working with the concept of People with Activity Limitations.

 

 

This practical Rule of Thumb is also what lies behind the concept of Maximum Credible User Scenario, i.e. building user conditions which are severe, but reasonable to anticipate …

 

         the number of people using a building may increase, on occasions which cannot be specified, to 120% of calculated maximum building capacity ;   and

         10% of people using the building (occupants, visitors and other users) may have an impairment (visual or hearing, physical function, mental, cognitive or psychological, with some impairments not being identifiable, e.g. in the case of anosognosia).

 

 

 

[ Please note well … that miserable piece of legislation … or, bureaucrats’ charter .. the 2005 Disability Act (Number 14 of 2005) … is irrelevant to the above discussion.  But … when Irish Politicians, Senior Civil Servants and the National Disability Authority begin to take seriously the 2006 United Nations Charter on the Rights of Persons with Disabilities … the 2005 Act will have to be scrapped altogether and/or dramatically re-drafted ! ]

 

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U.S. Disability Statistics – Practical Application in Europe ?

2009-02-25:  Back in 2003 … remember the European Year of People with Disabilities ? … or maybe you don’t, as there is a European Year for everything now ! … I belonged to a small group of people – the European Union Expert Group on Accessibility.  The Report issued at the end of our term included the usual statistic of 10% of people in Europe having a disability.  That figure, which always seemed a bit out of date and wide of the mark to me, continues to re-appear here, there and everywhere.  It is not reliable.  But … please read on.

 

As far as bureaucrats are concerned … if there are no statistics, a problem does not exist … and if there is no problem, there is no need to spend money.

 

But, that approach leaves policy makers who take their responsibilities seriously, NGO’s, people who design buildings and teachers, for example, in a vacuum.  No wonder awareness among the General Public is so low, and that there are so many participation restrictions and barriers in our Built Environment.

 

Questions relating to ‘disability’ in Irish Census Forms merely scratch the surface of this issue.

 

 

A recent Report, issued by the United States Census Bureau on 18th December 2008, may provide some useful information to guide front line policy and design implementation in Europe.  Please handle with caution, as these are NOT European statistics.

 

About one in five residents of the USA – 19% – reported some level of disability in 2005, according to the Report.  These 54.4 million people are roughly equal to the combined total populations of California and Florida.

 

Both the number and percentage of people with disabilities were higher than in 2002, the last time the Census Bureau collected such information.  At that time, 51.2 million, or 18%, reported a disability.

 

Among those with a disability, 35 million, or 12% of the population, were classified as having a severe disability.

 

Nearly half (46%) of people aged 21 to 64 with a disability were employed, compared with 84% of people in this age group without a disability.  Among those with disabilities, 31% with severe disabilities and 75% with non-severe disabilities were employed.  People with difficulty hearing were more likely to be employed than those with difficulty seeing (59% compared with 41%).

 

A portion of people with disabilities – 11 million aged 6 and older – needed personal assistance with everyday activities.  These activities included such tasks as getting around inside the home, taking a bath or shower, preparing meals and performing light housework.

 

Other Important U.S. Findings:

 

         Among people 15 years of age and older, 7.8 million (3%) had difficulty hearing a normal conversation, including 1 million being unable to hear at all.  Although not part of the definition of disability used in the Report, 4.3 million people reported using a hearing aid.

 

         Roughly 3.3 million people, or 1%, aged 15 and older used a wheelchair or similar device, with 10.2 million, or 4%, using a cane, crutches or walker.

 

         Nearly 7.8 million people aged 15 and older had difficulty seeing words or letters in ordinary newspaper print, including 1.8 million being completely unable to see.

 

         More than 16 million people had difficulty with cognitive, mental or emotional functioning.  This included 8.4 million with one or more problems that interfered with daily activities, such as frequently being depressed or anxious, trouble getting along with others, trouble concentrating and trouble coping with stress.

 

         The chances of having a disability increase with age: 18.1 million people 65 years of age and older, or 52%, had a disability.  Of this number, 12.9 million, or 37%, had a severe disability.  For people 80 years of age and older, the disability rate was 71%, with 56% having a severe disability.

 

         Among people 16 to 64 years of age, 13.3 million, or 7%, reported difficulty finding a job or remaining employed because of a health-related condition.

 

         Among people 25 to 64 years of age with a severe disability, 27% were in poverty, compared with 12% for people with a non-severe disability and 9% for those without a disability.

 

         Median monthly earnings were $1,458 for people with a severe disability, $2,250 for people with a non-severe disability and $2,539 for those with no disability.

 

         Parents reported that 228,000 children under age 3, or 2%, had a disability.  Specifically, they either had a developmental delay or difficulty moving their arms or legs.  In addition, there were 475,000 children 3 to 5 years of age, or 4%, with a disability, which meant they had either a developmental delay or difficulty walking, running or playing.

 

         There were 4.7 million children 6 to 14 years of age, or 13%, with a disability.  The most prevalent type was difficulty doing regular schoolwork (2.5 million, or 7 percent).

 

 

A Practical and Reasonable Application, therefore, of the above information in International & European Fire Engineering Practice is as follows:

 

Equivalent to the concept of ‘maximum credible fire scenario’, which was introduced by the Recommendations contained in the 2005 NIST Report on the WTC 9-11 Incident … the Fire Engineer (or other suitably qualified and experienced person) should develop his/her ‘real’ fire engineering strategy on the basis of a ‘maximum credible user scenario’, i.e. building user conditions which are also severe, but reasonable to anticipate …

         the number of people using a building may increase, on occasions which cannot be specified, to 120% of calculated maximum building capacity ;   and

         10% of people using the building (occupants, visitors and other users) may have an impairment (visual or hearing, physical function, mental, cognitive or psychological, with some impairments not being identifiable, e.g. in the case of anosognosia).

 

If more than token consideration is to be given to Fire Evacuation for All … these guidelines indicate, for example, how much space should be allocated to an ‘area of rescue assistance’ which adjoins – on every floor except ground level – a vertical fire evacuation staircase in a building.

 

Fire Evacuation Routes at ground level should be ‘accessible’ and lead directly to the exterior.

 

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