clearing our path
TRANSCRIPT
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Clearing Our Path Universal design recommendations
for people with vision loss
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Clearing Our Path
Universal design recommendations for people with vision loss
By: Lesley MacDonald National Coordinator
Accessible Design Service CNIB
CNIB, 2009
Acknowledgements
CNIB gratefully acknowledges the advice and assistance
provided by the project advisory committee:
Mary Jane Finlayson, Partner, Sweeny Sterling Finlayson &Co Architects Inc. Mark Iantkow, Director, Libertas Adult Education
Peter Parsons, Orientation and Mobility Specialist, CNIB Rob Sleath, Chair, Access for Sight-Impaired Consumers
Chris Stark, Manager, Monitoring, Liaison and Mediation, Accessible
Transportation Directorate, Canadian Transportation Agency
Thanks also to:
Gary Baldey (Section Reviewer) Morgan Ineson (Bibliography and Photo Captioning)
Julia Morgan (Editor) Rick Mugford, B.Arch (Illustrations)
Alexander Shaw (Photographer)
Please note that the contents of this manual reflect the views of CNIB. ISBN 978-0-921122-52-7
This edition of Clearing Our Path is dedicated with sincere gratitude to lawyer and volunteer disability rights advocate David Lepofsky. For three decades, David has worked tirelessly to remove barriers and foster equality and fairness for Canadians like himself who live with vision loss and for all Canadians with disabilities.
David's contributions have had a profound impact on disability rights and accessibility legislation in Canada, and his courage, wisdom, creativity, and determination remain an inspiration to us all.
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Contents
Preface ......................................................................................................................7
Chapter 1 Understanding the Needs of People with Vision Loss
1-1 Common eye conditions....................................................................................9
1-2 Mobility ............................................................................................................12
Residual sight
The long white cane
Guide dogs
Electronic travel aids
Sighted guide technique
1-3 Wayfinding ......................................................................................................16
1-4 Reading and writing ........................................................................................17
Print
Braille
Audio
Computers
Chapter 2 - Design Basics
2-1 Layout..............................................................................................................20
2-2 Lighting............................................................................................................21
Minimum lighting requirements
Types of lighting
Lighting styles
Placement of light fixtures
2-3 Colour/brightness contrast ..............................................................................31
2-4 Acoustics ........................................................................................................33
Chapter 3 - Exteriors and Interiors - Common Design Elements
3-1 Paths of travel ................................................................................................36
Protruding objects
3-2 Tactile walking surface indicators ....................................................................37
Attention TWSIs
Guidance TWSIs
3-3 Signage ..........................................................................................................41
Letter size, type style, and distance
Location of signs
Illumination of signs
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Colour contrast on signs
Tactile signs (raised print and braille)
Symbols and pictograms
Audible signs
3-4 Stairs ..............................................................................................................48
Location
Nosings
Treads and risers
TWSI
Handrails
Underside of stairs
Lighting
3-5 Ramps ............................................................................................................52
Width and landings
TWSI
Handrails
Edge protection
3-6 Platform edges ................................................................................................54
3-7 Information and communications systems ......................................................54
Information desks
Information telephones
Information kiosks
Public address systems
Tactile maps and pre-recorded instructions
3-8 Card, keypad, and other security systems ......................................................58
Chapter 4 - Exterior Design Elements
4-1 Exterior paths of travel ....................................................................................60
Location
Surface
Slope
Obstructions
Parking lots
4-2 Blended curbs ................................................................................................62
Identifying
Placement
4-3 Islands ............................................................................................................63
4-4 Accessible pedestrian signals ........................................................................64
Acoustic locator sound
Confirmation of activation
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Acoustic and tactile/vibrol walk signal
Confirmation of direction of travel
Push button location
Pedestrian crosswalks
Non-APS traffic signals
4-5 Roundabouts ..................................................................................................68
4-6 Landscaping ....................................................................................................68
4-7 Maintenance....................................................................................................69
Snow and ice removal
Regular maintenance
Construction sites
4-8 Building entrances ..........................................................................................70
4-9 Exterior doors ..................................................................................................71
Clear width
Door action
Hardware
Steps
Automatic sliding doors
Multiple doors
Revolving doors
Glass doors, glazed glass, and sidelights
4-10 Recreational facilities ......................................................................................75
Outdoor rest areas
Benches
Playgrounds and parks for children
Nature trails
Chapter 5 - Interior Design Elements
5-1 Entrance lobbies..............................................................................................79
5-2 Amenities ........................................................................................................79
5-3 Floor finishes, grilles, and mats ......................................................................79
5-4 Ticket counters and kiosks ..............................................................................80
5-5 Queuing systems ............................................................................................81
5-6 Interior circulation ............................................................................................82
Corridors and hallways
Handrails
Waiting areas
5-7 Public telephones ............................................................................................83
5-8 Escalators and moving walkways....................................................................84
Surfaces
Treads and risers
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TWSI
Lighting
Underside of escalators and moving walkways
Alternate access
Repairs
5-9 Elevators ........................................................................................................85
Elevator lobbies
Elevator cabs
Elevator control panels
Elevator telephones
5-10 Mirrors, glass, and sidelights ..........................................................................89
5-11 Doors ..............................................................................................................89
5-12 Specific rooms and spaces ............................................................................90
Theatres, performance spaces, and lecture halls
Cafeterias and dining rooms
Kitchens
Washrooms and shower stalls
Change rooms
Pools, gyms, libraries, and exhibition spaces
Chapter 6 - Emergency Exits and Safety
6-1 Emergency exits..............................................................................................98
Interior routes
Exit doors and hardware
Emergency exit signage
Exterior routes
6-2 Emergency alarms ........................................................................................100
Types of alarms
Placement of alarms
Photometric features
Alarm volume
6-3 Emergency lighting........................................................................................102
6-4 Areas of safe refuge ......................................................................................103
6-5 Life safety plan ..............................................................................................104
Glossary ................................................................................................................106
Bibliography ..........................................................................................................111
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Preface
According to Statistics Canadas recent Participation and Activity Limitation Survey,
more than 836,000 Canadians live with significant vision loss. Although many of us
would probably be surprised to realize the number is closing in on one million, this
number doesnt even begin to tell the tale. Consider that more than 4.25 million
Canadians have some form of macular degeneration, glaucoma, diabetic
retinopathy or cataracts. This group may not all live with significant vision loss
but they are certainly at risk.
Over 4.4 million Canadians (one out of every seven) live with some form of disability.
Thats a substantial group of users you cannot afford to overlook in your building
project or public space. Recognizing that your end users have a wide variety of
needs and abilities just makes good business sense. According to a recent study,
Canadians with disabilities account for an estimated $25 billion a year in consumer
spending and influence the purchase decisions of 12 to 15 million other Canadians.
Times are changing. Increasingly, we see people with disabilities taking their rightful
place alongside the rest of us in schools and universities, on buses and subways,
at public events, in the workplace, and everywhere else. Governments, both
in Canada and around the world, are passing groundbreaking disability rights
legislation. Additionally we are reaching new levels of societal awareness. More
and more of us intuitively understand that public services and spaces that people
with disabilities cannot access cannot accurately be described as public.
CNIB developed the first edition of Clearing Our Path in 1998 to address the need
for information on creating accessible environments for people with vision loss.
CNIBs recommended guidelines came out of 20 years of providing universal design
consulting expertise in Canada, not to mention our long history, going back to 1918,
of offering services and support for Canadians with vision loss and being the only
national organization to do so. Since its release, this manual has become an
invaluable tool for architects, designers, building owners, planners, standards
bodies, and others interested in making indoor and outdoor spaces universally
accessible.
This second edition of Clearing Our Path builds on the first by providing updated
information based on new research, new international standards, emerging
technology, and universal design principles.
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What has not changed is our commitment to universal environments for people
with vision loss. Architectural design does not need to create barriers that hinder
the safe use of a space or limit independent travel. There are many uncomplicated,
inexpensive solutions that consider people with vision loss and their needs and in
fact benefit all users. These solutions not only make a space universally accessible,
but can also enhance it aesthetically, since buildings that apply universal design
principles can also be beautiful. Implementing these solutions requires mainly
the application of simple techniques to make information about an environment
available in an accessible way. To read more about universal design and the seven
principles behind it, please see universal design in the Glossary.
We encourage you to use this manual to learn more about how people with different
eye conditions and different mobility techniques navigate a space, the many
principles that affect universal design, and the ways in which you can ensure
your building project meets the needs of people with vision loss.
The key to any successful universal design project is to start early if possible,
right at the beginning when planning the project. CNIBs team of universal design
consultants would be pleased to be of assistance in providing guidance on universal
design with a focus on the needs of people with vision loss. We can also involve
Canadians with vision loss to provide feedback on your plans.
Please note that throughout this manual, the term people with vision loss is used.
This term includes people who may experience a total or partial loss of vision. It
also includes people who are deafblind, who will also benefit from many of the
design features described in this manual. Please note that for the purposes of this
manual, we take as a starting point that public spaces already meet national and
provincial building and fire codes and similar regulations. Clearing Our Path is
meant to augment these codes; nothing in these guidelines shall override them.
When in doubt, the more restrictive provision should apply.
Universal design for the built environment means the design of spaces that are
usable by all. It is, without question, a broad-spectrum solution. Although we have
focused on vision loss, the solutions presented in this manual will almost always
benefit everyone, from children to adults to seniors. It is about making a space easy
to use and a joy to experience for every age and ability, and for all of the senses.
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Chapter 1
Understanding the Needs of People with Vision Loss
1-1 Common eye conditions
1-2 Mobility
Residual sight
The long white cane
Guide dogs
Electronic travel aids
Sighted guide technique
1-3 Wayfinding
1-4 Reading and writing
Print
Braille
Audio
Computers
1-1 Common eye conditions
There are many different eye conditions, and each one affects vision differently,
which means people with different eye conditions will have different needs in the
built environment. As a general rule, people who have limited central vision will have
more problems with reading signs and interpreting traffic lights than getting around
the built environment. Those who have limited peripheral vision but good central
vision may be able to read (signage, for example) but will have difficulty navigating
through a space.
Most people with vision loss nine out of ten are not actually blind but have
some level of vision: everything from light perception to some degree of partial,
usable sight. People with vision loss typically learn to maximize their remaining
sight when they are navigating the built environment.
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Here is how some of the most common eye conditions affect sight:
View of a building with full vision
Loss of Peripheral Vision
Commonly known as tunnel vision. The
centre of the visual field is functioning but
peripheral vision is absent. Glaucoma
and retinitis pigmentosa (RP) are
common causes of this type of vision
loss. People with limited peripheral
vision may need to be standing in front of
something or to turn their head in order to
see it, and can have difficulty navigating
through the built environment.
Loss of Central Vision
Central vision is absent, distorted or hazy
and peripheral vision functions to some
degree. People with a loss of central vision
have a limited ability to see fine detail and
colour and have difficulty with close-up
tasks such as reading, writing, or recog
nizing faces. This condition is most often
caused by macular degeneration, the
leading cause of vision loss in Canada,
which affects primarily adults over 50.
Loss of peripheral vision
Loss of central vision
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Blurred Vision
An inability to see objects in focus. This
condition can have many causes. Some
examples are extreme nearsightedness,
uncontrollable movements of the eye,
and cataracts.
Blurred vision
Night Blindness
Difficulty seeing under dark conditions. Night blindness is a common first
symptom of retinitis pigmentosa (RP). It is also common among older adults.
Diabetic Retinopathy
Symptoms include floating dark spots or
a lack of sharpness across the visual field.
Nearly all patients with Type I diabetes
and 60 per cent of those with Type II
develop some form of diabetic retinopathy
during the first 20 years they have
diabetes.
Diabetic retinopathy
Colour Blindness
A partial or total inability to distinguish one or more colours from each other. There
are three main kinds of color blindness. The inability to distinguish red from green
is the most common and occurs in men more often than women. The other major
types are blue-yellow colour blindness and the complete absence of colour in vision
(vision occurring in shades of black and white only).
Sensitivity to Glare
An inability to look at bright light without pain. In older adults, this condition is often
the result of cataracts caused by changes within the eyes lens.
Total Blindness
Among people with vision loss, a small proportion will have a complete absence of
vision. A person can be born totally blind or develop this condition later in life. Total
blindness may not mean blackness. A person might see nothing but grey or white,
for example.
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Deafblindness
Deafblindness is a combination of both hearing and vision loss. It affects everyone
differently. Some people who are deafblind may have some hearing and some sight.
Others may have no hearing and some sight, or no sight and some hearing. Still
others may have no hearing or vision at all.
1-2 Mobility
Mobility is the ability to move about or navigate a space from one point to another. It is important when designing spaces for people with vision loss to have an understanding of mobility. This section will provide you with an overview of how people with vision loss travel.
In general, people with vision loss choose one of several methods for mobility. They
may travel independently, relying on their residual sight or using a mobility aid. The
three most common mobility aids in the order of their frequency of use are the long
white cane, the guide dog and the electronic travel aid.
People often combine their use of residual vision with their use of a mobility aid. For
example, light perception can be used effectively in conjunction with a mobility aid.
Finally, people with vision loss may choose to travel with a sighted escort (also
called a sighted guide) in some situations
Examples of people with vision loss using different mobility
methods and the space that would be required in each case.
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Residual sight
People with vision loss who have some usable vision may be able to navigate by
learning to use their remaining vision more effectively. Many people in this situation
enhance their remaining vision with the use of low vision aids and visual efficiency
training. However, people who normally travel using residual sight but who have
night blindness, may, under poor lighting conditions, turn to a mobility aid to ensure
safe and independent travel.
The long white cane
There are several types of white canes that people with vision loss use.
A person may use a shorter white cane called an ID cane for the primary purpose of
identifying himself or herself as a person with vision loss so that others will respond
appropriately by not impeding the path of travel or by offering assistance. People
who use an ID cane may also rely on a sighted guide or use their residual vision for
mobility.
Some people with vision loss use a white support cane to assist with balance. An
elderly person who needs extra support and stability may use this type of cane, for
example. Someone using a white support cane may still pair this with the use of
residual vision or another mobility aid.
The white cane that is most often used for mobility and most often used in general
is called the long cane. The long cane assists with object detection and depth
perception, and provides advance information of gradient changes and upcoming
barriers or dangers in the path of travel. In addition, and as with the other white
canes, the long cane serves to identify that a person has vision loss.
People who use the long white cane sometimes go through formal instruction on
how to use it, called orientation and mobility training. Instruction with the long
cane provides people with skills to travel safely, independently, and gracefully in
their environment.
The long white cane is meant to ensure that objects in the line of travel below waist
level are detected. (Objects protruding into the line of travel above waist level will
not be detected unless they are properly identified at or near ground level, in which
case, they can be called cane detectable. For more information on protruding
objects and cane detectability, please see Section 3-1.)
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The primary cane technique used in an unfamiliar environment is called the touch
technique, in which users systematically tap the cane on the left and right side on
the ground in a wide arc, about 25mm beyond the widest part of their body. In addition
to providing information about objects in the path of travel, the touch technique can
provide the user with acoustic information.
Sometimes people may prefer a roller tip on the end of their cane. The roller tip is
swept across the path of travel to obtain information.
Many people do receive formal instruction on how to use a cane and are taught a
variety of cane techniques to meet particular situations. There are also people who
do not pursue formal orientation and mobility instruction and develop their own
strategies for the long white cane.
When people use their residual vision in conjunction with long white canes, typically,
they will use their vision to detect objects above waist level and their canes to detect
objects below waist level. For example, someone who has good central vision but
limited peripheral vision may use their vision to detect objects right in front of them
(such as tree branches and road signs), but use their cane to detect obstacles at
ground level.
Guide dogs
Guide dogs usually Golden or Labrador Retrievers or related crossbreeds are
used by many people who have vision loss as a mobility aid. When the guide dog is
working it will be equipped with a harness that the handler with vision loss grasps.
When a guide dog is not working, the handler will usually release the harness and
control the dog simply using a leash. There are a number of schools located in
Canada and the United States where a person with vision loss can receive instruction
in the use of a guide dog.
Unlike the long white cane, which is used to detect obstacles, guide dogs work in
partnership with their handlers to react to obstacles. Once trained, guide dogs learn
to stop at elevation changes and to lead their handlers around dangerous areas
(construction, for example) and away from overhanging protrusions. The handler is
always in charge, and gives directions to the dog (turn right, turn left, etc.) so that
they can get from one point to another as a team.
In Canada, provincial legislation permits a person accompanied by a guide dog to
enter or use any space that is customarily available to any other member of the
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public. In terms of the built environment, dedicated guide dog relief areas or other
grassy areas should be made available wherever possible for people who use guide
dogs. Please see Section 4-5 for more on this subject.
Electronic travel aids
An electronic travel aid (ETA) is a device that emits energy waves to detect objects
in the environment within a certain range. The ETA will process reflected information
and provide it to the user, usually through vibrations, sounds or voice announcements.
ETAs may operate on laser or sonar waves, and today, global positioning system
technology is also being used.
Some ETAs are used as a primary mobility aid, and others are more likely to be
used as a secondary aid in conjunction with a long cane or a guide dog. ETAs may
provide a degree of sensory information about an environment that under the most
ideal situations would not be possible to obtain when using only a long cane or a
guide dog. For example, many portable GPS devices now announce names of
streets and major public buildings.
Sighted guide technique
People with vision loss occasionally find that there are times when travelling with a
sighted escort comes in handy: for example, in crowded situations like office parties,
at street crossings, or in unfamiliar places. People who have recently lost their sight
often travel with a sighted guide as well.
A person with vision loss may still choose to use other mobility aids, for example a
long cane, at the same time that they are making use of a sighted guide.
There is a specific technique involved in acting as a sighted guide that is designed
to be respectful of people with vision loss and their independence.
In this technique, the person with vision loss will gently grasp a sighted guides arm
from behind, just above the elbow. The guide will hold her arm in a straight, relaxed
position and the person with vision loss will stand to the side about half a step behind.
The person with vision loss will also keep their arm relaxed, with the elbow bent at
about 90 degrees and held close to the body. The sighted guide and the person with
vision loss will then walk comfortably in tandem.
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For more about this technique, please see CNIBs Step by Step publication at
www.cnib.ca.
1-3 Wayfinding
Whereas mobility is defined as getting from one destination to another, the term
wayfinding encompasses the process of using cognitive and perceptual information
to get to that destination. Wayfinding also involves orientation, the process by
which someone with vision loss determines where they are in a space at any given
moment.
Wayfinding design involves organizing the built environment to provide useful
information for wayfinding. Environments that include universal design principles in
wayfinding take into account all the human senses not just sight and all modes
of travel not just walking in both the design and maintenance of an indoor or
outdoor space.
People who cannot rely entirely upon sight for wayfinding often use a combination
of other strategies:
They may make a memory map of important parts of a building (for example,
I need to turn left as soon as I enter the building to get to the elevators).
They may rely on the physical feel of changes on the walking surface detectible
by foot or with a long white cane. For example, they may notice that a walkway
changes from concrete pavement to a metal grate just before a building entrance
or that a textured-tile lobby changes to carpet at the beginning of a hallway.
They may find an accessible pedestrian signal useful when crossing a road.
They may use contrast in colour and brightness in the surroundings.
They may also get directions and a description of the space layout from tactile
signs and maps or computer stations.
They may use audible clues.
They may obtain descriptions of how to get to a specific spot from people at
information booths.
The following design features are basic elements of wayfinding used by people who
have vision loss, and will be explored in detail in the rest of this manual, particularly
in chapters 2 and 3:
Logical and intuitive space
Textural contrasts and tactile cues
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Acoustics
Colour and brightness contrast
Signage, including tactile, braille, and audible signs
Appropriate, well-designed lighting
People who have vision loss may use any combination of these design elements in
wayfinding. It depends on their level of vision, their orientation and mobility training,
their prior knowledge of a space, and their needs at any given time.
1-4 Reading and Writing
Just as there are several different methods of mobility that people with vision loss
use, there are also a number of methods for reading and writing. The method that
someone uses depends on many factors, such as their degree of usable vision,
their background and training, and their preferences.
Print
Someone with vision loss who has enough usable vision to read print may use an
aid such as a magnifying glass or telescopic glasses to read print. More often, large
print (16 point text and above) is preferred, even though readers still may require an
aid such as a magnifier. There is no one size fits all acceptable font size for large
print; the preferred type size for one user may be too small or too big for another.
Nevertheless, CNIB has a set of recommended guidelines for accessible print and
design on the printed page, called the Clear Print Accessibility Guidelines, which
sets out principles to follow to benefit a majority of users. You can find this at
www.cnib.ca. CNIB recommends following this standard for any printed materials
that are available for the public to use, such as information cards, brochures,
restaurant menus, etc.
Someone with a significant degree of vision loss who has read print in the past may
still be able to read raised print letters by touch. The primary use of this method
would be for signage. Signage accessibility comes with its own set of guidelines,
which are discussed in detail in this manual in section 3-3.
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Braille
Braille, invented in 1824 by Louis Braille, is a system of small raised dots that are
read using the fingertips. Braille can be used to represent everything from words to
mathematic symbols to music.
While only 10 per cent of people with vision loss use braille as their primary reading
method, many more use braille for tasks such as labeling cupboards and prescription
bottles at home or reading signs on elevator buttons and other key features in the
built environment.
For people who use braille as their primary reading method, braille is extremely
important. It fosters literacy, allows someone to read independently and in private,
provides a method for writing, and can be a fast and efficient way to read (unlike
print, which can be tiring to read at length for many people with vision loss). As well,
someone with congenital vision loss may not be familiar with print characters and
will most likely use braille to read.
Braille may not work for all readers, though. For example, someone who has
decreased sensitivity in his or her fingers as a result of diabetes may not be able
to use braille. People who lose their sight at an elderly age may choose not to use
braille, except perhaps for simple labeling around the house.
There are two main types of braille: uncontracted and contracted. Just as sighted
people have shorthand, some people with vision loss use a contracted version of
braille that is space saving and allows for rapid reading and writing. However, since
not all braille readers know contracted braille, it is not always appropriate in the built
environment. Section 3-3 has many recommendations on when and how to use
braille in signage.
In Canada, standards for producing braille codes in English and French are
determined by the Canadian Braille Authority (CBA). CBAs recommendations are
found at www.canadianbrailleauthority.ca. When having braille created for the built
environment, it is important to make sure that your producer is following CBAs
guidelines.
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Audio
Many people with vision loss choose to read audio formats, either as their primary
reading method or in addition to other methods such as large print or braille. The in
ternational standard for audio information for people with vision loss and other print
disabilities is called DAISY (Digital Accessible Information System). For more infor
mation, see www.daisy.org.
Computers
People with vision loss have benefited a great deal from technology and the
computer age. Someone may use a computer (and the Internet) using a number
of methods. The three most common are:
Screen-magnifying software: software programs that allow a user to choose a
desired magnification level for what is shown on a computer screen.
Screen-reading software: software programs that use a synthetic voice program
to indicate whatever is typed or read on a computer screen.
A refreshable braille keyboard: a keyboard that typically fits just below a standard
computer keyboard and contains one line of braille text. Once the user reads one
line, he can press a key to refresh the line, and metal pins will pop up or down
to reflect a new line of braille.
In addition, computers and digital technology offer many more reading methods
for people with vision loss. A person who has vision loss may read streamed audio
content on computers. Or they may download digital text, audio, or braille files to
read at their computer or on portable electronic devices.
However, computers and digital technology have their own set of accessibility
requirements not all websites or computer workstations are accessible for people
with vision loss, depending on how they have been created. In the built environment,
this will affect electronic aids such as information kiosks and video terminals.
Please see Section 3-7 for CNIBs guidelines for these stations. For general
information on accessible website design (which also applies to the accessibility
of any computer kiosk or workstation), see the Web Accessibility Initiative at
www.w3.org/WAI/gettingstarted.
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Chapter 2
Design Basics
2-1 Layout
2-2 Lighting
Minimum lighting requirements
Types of lighting
Lighting styles
Placement of light fixtures
2-3 Colour/brightness contrast
2-4 Acoustics
This chapter discusses four basic design elements for creating accessible built
environments that underline all other recommendations and guidelines in this manual.
2-1 Layout
People with vision loss can more easily memorize and become familiar with a space
when it is logically planned and defined. This is particularly important in public
spaces that people use frequently, for example, public transit stations, banks, and
supermarkets.
CNIB recommends a logical and straightforward layout for both the exterior and
interior of any designed environment. The main entrance should be directly
accessible from the principal routes of travel sidewalks, transit stops, parking
lots, etc. Reception areas should be close to the main entrance of a building.
Large open areas (such as large reception halls, courtyards, and airport terminals)
can be difficult for people with vision loss to traverse without losing their orientation.
When you have such a space in the built environment, use a tactile walking surface
indicator or a strip of material that is texturally different as well as colour contrasted
with the surrounding surface.
A space that is well defined and uses straight lines and consistent right angles in
its layout allows people with vision loss to maintain their orientation. Hallways and
pathways should be straight, not curved, and turns should ideally be close or equal
to 90 degrees.
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The layout of floors should ideally be identical (or as close as possible to identical).
For example:
Halls and washrooms should be in the same location on each floor so the
information someone learns on one floor can be applied to another floor.
Essential features, such as washrooms, elevators, and staircases, should be
grouped together whenever possible in one central area of the building.
Stairs and elevators should be located close to each other.
Mens and womens washrooms should be located next to each other, and if
possible, accessed from the main circulation route.
Washrooms should be available without having to go up or down a set of stairs.
Changing the layout of a public space can present a problem for regular users of
the space who have vision loss. For example, the continuous repositioning of sale
tables in grocery and department stores is frustrating and at times dangerous for
someone who does not see well. In general, CNIB recommends that changes to
the layout should be avoided.
2-2 Lighting
Good lighting is the single most important tool in the built environment for most
people with vision loss, because it helps to reveal most of the key areas in a
space (stairs, signage, etc.). Lighting is also one of the most complex elements
of architectural design.
As people age, they require more light for their eyes to function effectively. An adult
in the middle to senior years will need much more light to see well than a younger
person. As well, someones lighting needs can be affected by an eye condition. The
same level of light may be fine for a fully sighted person, excessive for someone
with glaucoma, and too low for someone with macular degeneration. Because of
these variations, CNIB cannot recommend one set of guidelines that will meet all
needs. However, here are a few general concepts to bear in mind when designing
lighting for a built environment.
Minimum lighting requirements
Existing legislation and standards outline minimum lighting requirements for people
who are sighted, but do not provide definitive lighting levels for people with vision
loss. In general, CNIB recommends increasing the current Illuminating Engineering
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Society (IES) of North America suggested lighting levels by a range of 25 to 50 per
cent. This recommendation is in line with other current guidelines such as Building
Sight, published by the United Kingdoms Royal National Institute of Blind People.
In addition, here are CNIBs recommendations for good lighting levels for people
with vision loss in specific parts of the built environment:
Location Lighting Level (in lux)
Halls, lobbies, waiting areas 200
Inquiry/reception stations 500
Circulation areas: corridors, elevators, stairs 200
Lounges 200 to 300
Kitchen and food preparation areas 200 to 300
Offices, general lighting 500
Computer workstations 300 to 500
Types of lighting
There are six principal types of lighting: natural light, traditional incandescent light,
fluorescent light, halogen light, HID (High Intensity Discharge), and LED (light
emitting diodes). Each one affects people with vision loss in different ways.
Both natural light and artificial lighting can cause glare, which can literally blind a
person with vision loss. The effects of glare are compounded when materials with
a high gloss level are used. CNIB recommends that low-lustre finishes be used for
all vertical and horizontal surfaces.
Natural daylight
Natural daylight, which comes from the sun, is the source by which all other light
sources are judged, and its use has advantages and disadvantages. Although
daylight is widely accepted as having a positive psychological effect on people,
outdoor luminance varies greatly it can be as high as 120,000 lux when there is
direct sunlight at noon, which can be painful to look at, or it can be as low as 5 lux
when there are storm clouds and the sun is at the horizon. People with vision loss
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may have problems adapting to different amounts of natural light on days that are
intermittently sunny and cloudy.
Natural daylight is one of the greatest causes of glare and shadow in building
interiors. Inside a building, daylight should be diffuse and even, without causing
glare or shadowing. Both can be problematic for people with vision loss. Fortunately,
there are many effective methods to control glare and shadow, such as tinted
window glass, translucent wall panel systems, and exterior awnings and canopies.
Special films that reduce solar and visible radiation can be installed on existing
windows and glazing.
Moving in and out between areas of great contrast in light levels is particularly
difficult for people with vision loss. It is important to try to moderate light levels.
Near entrances, moderating light levels is particularly important; the levels inside
and outside should be as close to equal as possible.
When it comes to the built environment outdoors, the effects of natural lighting and
shadowing need to be taken into consideration when deciding where to place items
such as staircases and entrance canopies. Entrance canopies can be effective in
reducing glare from natural light sources, but should not hide the entrance from the
view of a person with vision loss. Similarly, staircases located outside should be in
clear view at all times and should not be overshadowed by canopies or other objects.
For buildings there is much that can be done to mitigate both glare and solar heat
gain. Exterior sunshades protect the exterior skin from direct exposure and eliminate
glare. On the interior, window coverings with a maximum of 3 per cent open fabric
(1 per cent recommended
for west exposures) can be
automated to respond to a
glare condition. Computerized
control systems allow the glare
condition to be defined to suit
the users of the occupied
spaces and this can be
modified easily if the use
changes.
Loblaw Companies Limited
SSF & Co Architects Inc.,
exterior sunshade louvers
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Loblaw Companies Limited SSF
& Co Architects Inc., the same
louvers, viewed from the interior.
The light shelf is in the horizontal
position. The louvers are in the
same plane and partly visible. A
rigging system raises and lowers
the light shelves and the valence
of the window coverings in
response to late, low afternoon
sun penetrating the building.
Natural lighting can be enhanced with the use of light shelves, which are horizontal
planes or a series of parabolic louvers about 2.28m off the finished floor that
bounce indirect light off the ceiling and deeper into the building.
When these are used in tandem with automated artificial lighting controls that turn
off light fixtures when there is adequate natural light, it not only provides more
glare-free, indirect light, it saves energy.
Skylights and other sources of natural light should be positioned so that sunlight
does not shine directly into an interior space. Where this is not possible, use tinted
glazing or incorporate a shading device.
Incandescent lighting
Incandescent lighting is produced by light bulbs that give off both heat and light
and is generally a good alternative to natural light. Because incandescent lighting
has a colour spectrum closer to natural light than many other light sources, it was
traditionally the preferred light source for general-purpose illumination.
However, due to their relative inefficientcy from an energy standpoint, incandescent
light bulbs are being replaced in many applications by other devices such as
flourescent lamps, HID, and LEDs, which give more visible light for the same
amount of electrical energy input. Some jurisdictions are attempting to ban the
use of incandescent lightbulbs in favour of more energy-efficient lighting.
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Fluorescent lighting
Fluorescent lighting consumes less electricity, lasts longer, and does not radiate
much heat compared to incandescent bulbs. Fluorescent lighting can come in the
form of tubes that create a line of light (the traditional lighting environment in large
buildings and offices) or in bulbs knows as compact fluorescent lamps (CFLs).
CFLs provide good overall light and are becoming increasingly popular in the built
environment. Many jurisdictions encourage their use as an energy-saving measure
through incentive programs and legislation.
Compared with an incandescent lamp, a fluorescent tube is a more diffuse and
physically larger light source. In suitably designed lamps, light can be more
evenly distributed without a point source of glare such as seen from an undiffused
incandescent filament.
Fluorescent lighting has a major disadvantage in the slight flicker it produces,
although there are ways to counteract this effect, such as using proper lenses
or shielding the light source to provide even, indirect lighting. Another method of
reducing the flickering effect of fluorescent lighting tubes is to use two tubes operating
in phase opposition. These fixtures, when used as an indirect light source or when
combined with prismatic diffusion covers, lattices, translucent shades, or cover
panels, produce a substantially reduced flicker.
Fortunately, today most offices are well designed in terms of lighting banks of
over-bright, improperly shaded fluorescents are mainly a thing of the past.
Fluorescent lighting comes in a range of shades in the light spectrum. In the past
fluorescent lighting came in cool blue tones that were not a good match for natural
light or incandescent light. However, today better formulations of phosphor on the
inside of the tubes have provided warmer tones. The best soft or warm white
fluorescent bulbs available now are similar in color to standard incandescent lighting.
CNIB recommends the use of dimmable fluorescent lighting fixtures, which use
electronic ballasts that work at a high frequency to reduce both the flicker of the
light and the energy they consume. Light with a reduced flicker is more acceptable
for older adults and people with vision loss as it is less tiring and distracting
particularly for those who rely on peripheral vision.
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Designers wishing to use a linear arrangement of fluorescent lighting in corridors
can take advantage of their directional attribute to assist those with vision loss by
installing the tubes in one of two ways:
Centre: Placing the light fixture in the middle of
the corridor provides a visual clue for orientation
by helping to define the right and left sides of the
corridor. This can be achieved by either indirect or
direct lighting. In the case where indirect lighting
is used, the center of the corridor ceiling appears
as a dark line with even, diffused, indirect, no-glare
light on the ceiling.
A good example of colour contrast and
width in a hallway. The central overhead
lighting is also useful for wayfinding.
Sides: Placing light fixtures at the two sides of the corridor where walls and ceiling
meet provides a similar visual clue that defines the width of the passageway and
facilitates navigation. In this case the lighting is indirect the fluorescent tubes
are tucked into valances or light coves along the sides. The bulbs are not visible
and the cove system produces an acceptable soft light effect.
Tungsten-halogen lighting
Tungsten-halogen lighting is a type of incandescent lighting where a bulbs filament
is surrounded by an inert gas and a small amount of halogen, which makes the bulb
more efficient and increases its lifespan.
Halogen lighting produces a bright white light and provides more light per watt than
regular incandescent bulbs, which makes it a good source of task lighting. Because
halogen lights are so bright, the positioning of light bulbs needs to be considered
very carefully to reduce glare and shadow.
Halogen lights also give off a great deal of heat, and this needs to be considered in
any built environment so that they are not a safety hazard. Do not position halogen
lights where someone with vision loss could inadvertently sit or stand underneath
and be injured from the heat. If sight would be required to notice the danger, the
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lights should be moved out of the way, or use a barrier such as a railing to prevent
injury.
LED
LED lighting emits an energy-efficient source of light when electricity is applied to a
simple circuit. LED bulbs produce a light that is very similar to daylight and therefore
these bulbs are very practical and useful.
LED bulbs provide a bright, focused point of light. They are designed as directional
bulbs, which means they can be turned to focus on an object or location. They
produce no UV radiation and little heat, making them ideal for illuminating objects
that are sensitive to UV light, such as works of art.
Traditionally used as indicator lights on electronic devices, LED bulbs are now
being employed in many wider applications including in signage, streetlamps, and
architecture detail lighting. LED lighting is also used as task or spot lighting, for
example under kitchen countertops.
LED sources also:
Light up instantly
Can be easily dimmed
Operate silently
Require only a low-voltage power supply (which increases safety)
At the time that this edition of Clearing Our Path was written, LED lighting did not
have a favourable price point for general lighting when compared to fluorescent and
other types of lighting, but they seem to hold much promise for the future in providing
a greener solution for our lighting needs.
High-intensity discharge (HID)
High-intensity discharge (HID) bulbs are a type of arc lamp that have a longer life
and provide more light (lumens) per watt than any other light source. They are
available in mercury vapor, metal halide, and high- and low-pressure sodium types.
Low-pressure sodium vapor lamps are extremely efficient. They produce a deep
yellow-orange light and have an effective Colour Rendering Index (CRI) of nearly
zero. Items viewed under their light appear monochromatic, which has implications
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for people with vision loss. Metal halide and ceramic metal halide lamps can be
made to give off neutral white light, which is useful for applications where normal
color appearance is critical, such as TV and movie production, indoor or nighttime
sports games, automotive headlamps, and aquarium lighting.
High-pressure sodium lamps tend to produce a much whiter light, but still with a
characteristic orange-pink cast. New color-corrected versions producing a whiter
light are now available, but some efficiency is sacrificed for the improved color.
HID lamps are typically used when high levels of light over large areas are required,
and when energy efficiency and/or light intensity are desired. Typical locations
to use these lights include gymnasiums, large public areas, warehouses, movie
theaters, football stadiums, outdoor activity areas, roadways, parking lots, and
pathways. More recently, HID lamps, especially metal halide, have been used in
small retail and residential environments. HID lamps have made indoor gardening
practical, particularly for plants that require a good deal of high intensity sunlight.
Lighting styles
There are many styles of lighting, which all have different considerations when it
comes to people with vision loss.
Spotlighting casts a strong light on a small area.
In normal circulation routes or work areas, spotlighting is usually not recommended
because it can create strong contrasts causing eye adaptation problems for people
with certain kinds of vision loss. Spotlighting is best used to supplement general
illumination by highlighting specific features or as task lighting to light a specific
work location.
For example, hotel reception desks or bank counters may wish to use overhead
spotlights directly above the counter area to aid in reading and writing this benefits
many people with vision loss who still have some usable vision. (Note that these
lights need to be positioned so that users do not create shadows on their own work
surfaces.)
An office area with a general lighting level of about 500 lux would benefit from task
lighting from adjustable desk lamps providing illumination levels from 1000 to 1500
lux. However, the same desk lamps used in an area with a lower general illumination
level of 50 lux will create eye adaptation problems, because the light contrast
between the general light level and the workstation is too great.
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Where task lighting is provided close to the user, fluorescent lighting in the form
of CFLs may be appropriate, as they do not generate the heat of incandescent or
halogen illumination, which can be a hazard.
Uplighting and indirect lighting reflect light onto a ceiling or wall, which then
indirectly illuminates a space. These options are often a good way to provide lighting
without strong shadows or glare.
Uplighting or indirect lighting can be accomplished with different lighting designs
or lamp types. The three most common types are suspended indirect fixtures,
freestanding uplights, and wall sconces.
Suspended indirect fixtures can provide even diffused lighting in many applications
and in spaces of varying size. These fixtures are hung 4500 to 6100mm below the
finished ceiling and are designed with reflectors that provide an almost 180 degree
spread of light that washes the ceiling evenly. Combining indirect lighting with task
lighting allows flexibility to respond to specific light needs for users who need
brighter, more localized lighting.
Reflecting light off a ceiling mitigates glare on items such as computer screens and
signage, especially when compared to traditional ceiling-mounted lighting.
Loblaw Companies Limited SSF & Co Architects Inc. The light shelf at the
perimeter is mostly covering the upper window. It has automatically moved
into the up position to mitigate a glare condition. Normally it is in the
horizontal position and functions to bounce light deeper into the building.
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Freestanding uplights are recommended in small spaces because they can be
moved to suit the activity. The reduced brightness that results from reflecting light
off a ceiling can be counteracted by increasing the wattage of the bulbs or by using
more powerful fixtures.
Wall sconces with an upward component reflect light off a ceiling as well as the wall
on which they are mounted. Although they do not have the flexibility of freestanding
uplights, by positioning them at regular intervals, they can be used to create a visual
rhythm that can help people find their way through spaces such as public corridors.
They can also be positioned to focus on specific features such as doorways.
Placement of light fixtures
Both exterior and interior lighting should be directed to avoid glare and reflection
and to maintain a consistent pattern and level of light. The type and placement of
lighting should not cause the shadowing of building elements that need to be seen.
Consistent use of different types of lighting can provide useful directional cues and
help people with vision loss differentiate between different areas in a space. For
example, one type of light can be used to provide pathway lighting and another type
can be used for a parking lot.
Here is a checklist for good lighting placement:
Avoid glare. Glare and reflection, often caused by shiny or glossy surfaces,
can cause visual confusion. Check light fixtures from all angles at their proposed
mounting height to identify surfaces in the area that may produce glare, and
then make any necessary adjustments to the lighting or the surfaces.
Place light sources to avoid creating problem shadows. Shadows, whether
caused by natural or artificial light, can hide important features and create optical
illusions. For instance, a shadow can appear to be the edge of a table or part of a
building or might hide an obstruction from view.
Distribute light levels evenly at working and walking surfaces. Changes in
lighting levels should not exceed a range of 100 to 300 lux from one space to
the next, for example, from an elevator to a corridor.
Include task and spotlighting to augment the overall lighting system. This is an
economical means of providing extra light for certain areas without having to light
the entire space brightly. Task lighting is also essential for many people with
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vision loss who require extra light for detailed tasks such as reading and writing
and it benefits everyone.
Use dimmer switches and high-wattage light bulbs whenever possible and
appropriate so that lighting levels may be adjusted to suit the different needs
of different users of the space.
2-3 Colour/brightness contrast
It is impossible to overemphasize the importance of colour and brightness contrast
in the way people negotiate and understand the built environment. A person with
20/20 vision could enter a well-designed and logically organized building with good
signage, little or no glare, and minimum shadowing and still experience a sense of
disorientation when there is very little contrast in the colour or brightness of the
surroundings. These problems increase dramatically for a person with vision loss.
Colour contrast is the degree of difference between one colour and another on
the colour wheel. The more visually different the colours, the greater the contrast.
Brightness contrast (also known as luminance contrast) can be described as the
difference in brightness between one object or surface and another. The greater the
difference in brightness levels, the greater the contrast.
In the built environment, colour and brightness contrast can be used effectively for
many purposes. For example, they can be used to identify a door opening, to draw
attention to signage, and to define a route of travel. Colour and brightness contrast
can also be used for orientation. For example, a building designer may choose to
use different colours for different sections or floors in a building. However, providing
colour and brightness contrast at every turn or change in architectural detail can be
confusing. Consistency and simplicity are also important.
All parts of a built environment must be considered when it comes to colour and
brightness contrast to benefit someone with vision loss. For example, a light-coloured
door against a light-coloured wall may be more easily identified when the doorframe
and door are a dark colour such as brown. A sign is much easier to locate when it is
colour/brightness contrasted with the surrounding wall surface.
CNIB recommends that wherever possible, the colour and brightness contrast of
key elements in the built environment should be 70 per cent or more, based on the
following formula. To measure the colour and brightness contrast, use a light meter.
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Hold it 200 to 250mm above the brighter area (B1) and then above the darker area
(B2) and then use these measures in the formula.
Colour/Brightness Contrast = B1 B2 x 100
B1
B1 is the light reflectance value (LRV) of the light area.
B2 is the light reflectance value (LRV) of the darker area.
Here are CNIBs recommended guidelines in terms of colour and brightness
contrast. They should be applied to both exterior and interior spaces and signs:
Use noticeably different colours side-by-side to distinguish different key building
elements. Some good combinations are:
black/white
yellow/black
chocolate brown/white
dark blue/white
dark red/white
dark purple/white
dark green/white
orange/black
Avoid using these colour combinations, which have very poor contrast:
yellow/grey
yellow/white
black/violet
red/black
grey/white
light blue/white
red/green and blue/green (both are particularly
difficult for people with colour blindness)
Generally, white lettering set on a dark background is easier for people with
vision loss to read in comparison to dark letters on a white background. For
more information, please see Section 3-3, Signage.
Limit the use of colours and avoid large-scale patterns. Too many colours used in
a design can create confusion, as can large-scale patterns. Keep colour schemes
simple.
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Be consistent in the use of colours to convey specific information. For example,
you could use the same colour on the entrances to all of the womens washrooms
in a building and a different, contrasted colour for the mens washrooms.
When it is impossible to adjust the colour or contrast of an item, consider other
options. For example, when the colours used in a corporate logo cannot be
changed and the logo includes colours that do not contrast well with each other,
CNIB recommends placing a contrasting border around logo signage so that a
person with vision loss can more easily see it.
2-4 Acoustics
Sounds can give a person useful information about a space. Someone may use
reflected sound by snapping his fingers, tapping a long white cane, or making
another noise to listen for a reflected sound (a process known as echolocation).
This may help him to detect the size of a room, the presence of corridors, or the
proximity of walls, poles, or other structural barriers, for example. Within a built
space, specific sounds can provide someone with vision loss with cues about
the location of specific features, such as elevators. However, the space must be
designed to allow all of these sounds to be heard.
Inappropriately high levels of reflected and ambient sound are one type of sound
barrier called sound glare or sound masking. Sound glare interferes with the
process of locating an auditory cue and can confuse and tire a listener. Crowds
of people, construction or maintenance noise, a jet airplane passing overhead,
or background music in lobbies and elevators can all drown out useful auditory
information.
When a solid object is located between a sound source and a listener, it can create
a sound shadow. Sound shadows can be beneficial and provide useful information,
but they can also cause problems. For example, a temporary display, scaffolds used
for building maintenance and repairs, or decorative items that are positioned after
building construction can all distort or block critical sounds. This can cause a person
who is used to relying on specific sound cues for mobility to become disoriented.
A building designer cannot control every occurrence of sound glare or shadowing
but can take some steps to plan the acoustic character of a space and to minimize
the effects of sounds that could interfere with useful auditory cues. Here are some
points to consider when planning the acoustic design of a space:
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Well-defined, acoustically alive spaces are easier for people with vision loss to
traverse safely. Position water fountains, elevators, or escalators, for example, to
create useful sounds. A water fountain could be positioned to indicate a garden or
a reception hall, and an escalator would be a good indicator of a central location
that is an important part of the buildings design.
Carpets, acoustic ceiling tiles, and upholstered furniture absorb sound. The use
of these items dampens reflected sound. It is important to create a good balance
of sound absorption materials and materials that reflect sound so that people can
hear the space (get information about it through sound).
Sound sources may mask other sounds intended to provide important directional
cues. Consider the noise produced by, for example, ventilation ducts or
air-conditioning units. These sounds can be useful in wayfinding; however,
they should not obscure other important audio cues, such as the sounds from
an elevators arrival or a public address system.
Sound masking devices (for example, white noise devices) can be used
effectively in many situations to block unwanted noise, but make sure that
they do not dampen all sounds in a space.
Glass can be an effective sound buffer. Use double-glazed glass that has an
established sound-reduction capacity.
Reflected sounds that enable a person to use echolocation are frequently a good
source of auditory cues. Consider how the structure and texture of planned circulation
routes might interact with user-created sounds, such as those created by a tapping
cane, before building or retrofitting a space.
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Chapter 3
Exteriors and Interiors Common Design Elements
3-1 Paths of travel
Protruding objects
3-2 Tactile walking surface indicators
Attention TWSIs
Guidance TWSIs
3-3 Signage
Letter size, type style, and distance
Location of signs
Illumination of signs
Colour contrast on signs
Tactile signs (raised print and braille)
Symbols and pictograms
Audible signs
3-4 Stairs
Location
Nosings
Treads and risers
TWSI
Handrails
Underside of stairs
Lighting
3-5 Ramps
Width and landings
TWSI
Handrails
Edge protection
3-6 Platform edges
3-7 Information and communications systems
Information desks
Information telephones
Information kiosks
Public address systems
Tactile maps and pre-recorded instructions
3-8 Card, keypad, and other security systems
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3-1 Paths of travel
A path of travel is any space in a public facility where people might reasonably be
expected to move from one point to another. Paying attention to the design of paths
of travel is essential when considering people with vision loss, because an accessible
route will allow them to navigate public spaces safely and independently.
An accessible path of travel should ideally be straight, with right-angle (90 degree)
turns or as close to 90 degrees as possible.
A straight path is easier for people with vision loss to follow. Curved or winding
paths are more difficult to detect, more difficult to describe when giving verbal
directions, and more difficult for frequent users to memorize.
Pedestrian paths of travel should be designed to intersect as close to a right angle
as possible, and the intersecting paths of travel should continue in straight lines.
Protruding objects
Objects or signs that protrude into
the path of travel are potentially
hazardous to people with vision
loss unless they are located within
the detection range of a long white
cane.
Cane detectability
Objects or signs that are mounted less than 2030mm from the walking surface on
walls, columns, or freestanding supports should not protrude more than 100mm
unless they are cane detectable. To be cane detectable, a protruding object must
be located no more than 680mm above the walking surface. Someone using a long
white cane can detect an object when its lowest leading edge is no higher than
680mm above ground level.
If an object protrudes at a level higher than 680mm and below 2030mm, the object
can be made cane detectable if a railing, planter, or another barrier is placed at or
below 680mm from the walking surface to warn and stop someone from accidentally
bumping into the higher protruding object.
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The headroom in all pedestrian areas
should be at least 2030mm measured
from the walking surface. A height of at
least 2030mm is preferred at doorways,
arches, or tunnels; however a height of at
least 1980mm is acceptable at doorways.
When the overhead clearance is less than
2030mm from the ground surface (for
example, with sloped walls under stairs),
a guardrail or another cane-detectable
barrier must be provided with its leading
edge at or below 680mm from the ground
surface, to prevent a person with vision loss
from accidentally bumping into this hazard.
3-2 Tactile walking surface indicators
Tactile walking surface indicators (TWSIs), sometimes known as detectable warning
surfaces, are standardized walking surfaces that convey information to people with
vision loss through texture, and, occasionally, through sound.
TWSIs are typically made from inserts (metal, rubber, or plastic) or built directly into
concrete. They should have a texture that can be felt underfoot and detected by a
long cane. TWSIs should have beveled edges to decrease the likelihood of tripping.
There are two types of TWSI:
Attention TWSIs, sometimes called warning TWSIs, call attention to key hazards,
such as the start of a staircase or the edge of a platform in a subway station.
Guidance TWSIs, also known as wayfinding TWSIs, provide information about
the direction of travel through open spaces. They are designed to guide a person
on a designated path of travel.
A good example of making
an overhead obstruction cane
detectable using a railing as a
barrier.
A guidance TWSI
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TWSIs should be colour contrasted
with the surrounding walking surface.
Industrial yellow is the preferred
colour. However, a light colour on a
dark ground surface or a dark colour
on a light ground surface also works
effectively.
Attention TWSIs
CNIB recommends attention TWSIs
consist of circular, flat-topped domes
installed on a walking surface.
Attention TWSIs should have the
following specifications:
The height of the flat-topped
domes should be 5mm +/- 1mm.
The diameter of the top of the
flat-topped domes should be
between 12 mm and 20mm.
The diameter of the lower base of
the flat-topped domes should be
10mm +/- 1mm more than the
diameter of the top.
The distance between the bases of
adjacent domes should be a minimum
of 15mm.
The spacing between adjacent
flat-topped domes should be adjusted
depending on the size of the domes,
as shown in the table below. The
larger the individual domes, the farther
the space between them:
An attention TWSI
showing dimensions
An attention TWSI
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Top diameter of flat-topped Spacing between the centres domes (mm) of adjacent domes (mm)
12 55 to 61
15 57 to 63
18 60 to 61
20 63 to 68
CNIB recommends attention TWSIs should be used at the following locations:
Platform edges
Ferry dock edges
The edges of reflecting pools and fountains that are unprotected at ground level
The top of stairs
Both sides of ground-level railway crossings
Blended curbs
At the beginning of ground-level moving walkways (such as those used in airport
terminals)
When attention TWSIs are used on platforms and ferry docks, CNIB recommends
they begin 610 millimeters before the drop-off, running the full length of all
unprotected platform/dock edges that border the drop-off.
At stairs, attention TWSIs should commence one tread step before the nosing at
the top step, and they should be as wide as the stairs. The attention TWSI alerts a
person with vision loss that there is a set of stairs ahead and to seek the support of
a handrail to safely navigate them. The depth of the TWSIs used at the top of stairs
should be a minimum of 920mm.
At railway crossings, attention TWSIs should be located so that the edges of
TWSIs are 1.8m minimum and 4.6m maximum from the centerline of the nearest
rail. (Attention TWSIs should be installed in addition to any mechanical barriers that
are activated with the arrival of trains.)
Attention TWSIs should be set across the entire width of a blended curbs edge
(exclusive of flares), set back 150mm to 200mm from the curbs edge, and extend
a minimum depth of 610mm in the direction of travel.
For guidelines on TWSIs and moving walkways, please see Section 5-8.
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Guidance TWSI
CNIB recommends guidance TWSIs consist of a guiding pattern constructed of par
allel flat-topped elongated bars that extend in the direction of travel.
Guidance TWSIs would be appropriate at the following locations:
Bus shelters
Train stations
Subway platforms
Airports
Sports arenas/stadiums
Large open spaces, such as public squares
When guidance TWSIs are installed, the base surface should be less than 3mm
above the surrounding ground or floor surface so they do not create a tripping
hazard. TWSIs should always be adhered firmly so there is no likelihood of the
edges lifting.
CNIB recommends guidance TWSIs have the following specifications:
They should be a minimum width of 250mm and a maximum of 550mm.
They should have a minimum clearance of 600mm on either side of them.
The height of the bars should be 5mm +/- 1mm.
The width of the top of the flat-topped elongated bars should be between 17mm
and 30mm.
The width of the base of the bars should be 10mm +/- 1mm wider than the top.
The spacing between adjacent flat-topped bars should be adjusted depending on
the size of the bars, as shown in the table below. The larger the individual bars,
the farther the space between them:
Width of flat-topped bars (mm) Spacing between the centre of adjacent bars (mm)
17 72 to 78
20 73 to 80
25 75 to 83
23 80 to 85
When used to cross the path of travel, in locations such as bus shelters, guidance
TWSIs should be a minimum width of 550mm to ensure detection.
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3-3 Signage
Signs provide essential information to everyone. To accommodate the needs of the
general public, including people with vision loss, follow these basic guidelines:
Keep sign information short and simple. Easy-to-understand signs generate
confidence.
Be consistent in where you place signs. For example, mount signs at the same
height throughout a building.
Use typefaces, colours, and graphics logically and consistently.
Letter size, type style, and distance
Use upper case and lower case letters. Avoid using all capital letters, which
are harder to read because they do not provide as much visual information to
differentiate letters. Upper and lower case letters give words a more defined shape.
Also, avoid very fine type and very thick type, which both can be difficult to read for
people with vision loss.
CNIB recommends the use of sans serif fonts for signs, such as Tiresias Sign Font
(a font specifically designed for signs), Ad Sans, or Arial.
The following table gives recommendations for the size of lettering to use in
signs, depending on the distance from which they will be read. This table provides
examples of signage for a train station.
Character heights and intended viewing distances
Viewing Distance Character Height Usage
6m 200mm station entrance
4.6m 150mm station name, line name
2.5m 100mm train name viewed
from platform
2.3m 75mm line transfer information
1.5m 50mm route info display maps
750mm 25mm doors/rooms
750mm 20mm washroom (universal symbol)
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Location of signs
Place general information and orientation signage at key decision-making points at
eye level.
In crowded areas, signs can be placed above head level so as to increase their
visibility from a distance. However, there should also be a sign at a lower level for
those unable to read the higher sign, which should be in raised print (tactile lettering)
and braille. Tactile signs, including signs with braille, must be easy to reach and
touch.
CNIB recommends sandwich boards and freestanding movable signs not be used
because they are a tripping hazard for people with vision loss.
CNIB also recommends enclosed stairwells have signage inside and outside of the
stairwell to designate each floor, consisting of the floor number in Arabic numerals.
These signs should be permanently mounted on the wall on the latch side of the
door.
Illumination of signs
Sign lighting should not create shadows or glare. Use matte and non-glare finishes
to ensure a glare-free surface. The surface should be smooth and not strongly
backlit. Signs should have at least 200 lux of lighting to be read.
The effectiveness of light emitting diode (LED) signage will depend upon the colours
chosen and the angle of the sign relative to the general lighting of the area. LED
signs should be white, yellow, green, or light blue on a black background to achieve
the best contrast. Red LEDs on a black background are unreadable for most people
with vision loss, particularly those who are colourblind.
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Colour contrast on signs
CNIB recommends the contrast between a signboard and its surrounding surface
(such as a wall indoors or vegetation for a freestanding sign outdoors) should be
a minimum of 70 per cent based on the formula for colour/brightness contrast
described in Section 2-3.
White lettering set on a dark background is generally easier for people with vision
loss to read in comparison to dark letters on a white background.
A sign at eye level. The
sign is colour contrasted
with the surrounding wall.
Tiresias sign font is used
and colour contrasts with
the black background on
the sign itself.
CNIB recommends several effective combinations for signs when choosing colours
for a surrounding surface, sign background (signboard), and lettering:
Background surface: Light brick or light stone
Sign background: Dark (black preferred)
Lettering colour: White/yellow
Background surface: Whitewashed wall
Sign background: Dark (black preferred)
Lettering colour: White/yellow
Background surface: Red brick or dark stone
Sign background: White
Lettering colour: Black, dark green, or dark blue
Background surface: Green vegetation
Sign background: White
Lettering colour: Black, dark green, or dark blue
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Tactile signs (raised print and braille)
A tactile sign is any sign that can be read by
touch. Braille, raised print, and raised symbols
or pictograms are all examples of tactile signs.
CNIB recommends doors and openings that
lead to public spaces be identified by tactile
signage. The most effective location for a tactile
sign is on the wall on the latch side of the door.
When no wall space adjacent to a door latch
is available, a sign should be mounted on the
nearest adjacent wall. The sign should have a
clear wall area around it spanning at least A good example of a sign
75mm. Signage for doors should be consistently beside a doorway. The sign
placed, 150 +/- 10mm from the doorjamb. provides the same information
in print (upper and lowercaseTactile signs for washrooms are an exception letters with good contrast toin terms of placement. They should be placed the background), braille, and on the door, and an additional sign should mark raised print. the entrance to the washroom regardless of
whether the washroom is located in a recessed
area.
With double doors of any kind, signs should be placed on both sides of the doors.
The location of a sign should allow a person to approach the sign within 100mm
without encountering protruding objects or standing within a door swing.
Raised print signs are most useful for people with no vision at all or for people
whose remaining vision is sufficient to allow them to locate a sign but not sufficient
to read it.
Some people with vision loss may not know what print looks like and may therefore
be unable to read raised print. People who were born with almost no vision, for
example, are more likely to read braille exclusively. For this reason, all raised print
signs should be accompanied by braille.
CNIB recommends raised print signs be mounted between 1.35m and 1.525m in
height above ground level and located in a place where they can be touched without
causing an obstruction.
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Characters (for example, letters, numbers, and punctuation) on a raised print sign
should be higher than the surface of the sign by at least 0.8mm and by no more
than 1.5mm. The edges of the characters should be gently rounded. (Note that
half-rounded characters should not be used.)
Characters should be in sans serif font and be 16mm to 50mm in height (pictograms
and symbols should be larger see this section below). The characters should be
entirely in upper case, as upper case letters are easier to read by touch, compared
to a combination of upper and lower case letters.
Ideally raised print signs should be colour contrasted with the surrounding surface.
Raised borders around raised characters should be avoided, unless the border is
set far from the characters.
Braille signage is essential for conveying information to people with vision loss.
CNIB recommends using braille signs frequently and appropriately to identify key
features in the built environment. Use uncontracted braille for signs that have 10
words or less and contracted braille for signs with more than 10 words.
Raised print characters should be accompanied by uncontracted braille. Braille
dots should have a dome or rounded shape for easy recognition.
CNIB recommends the following measurement ranges for braille signage:
Braille dot base diameter 1.5mm
Braille dot height 0.6mm to 0.8mm
Distance between any two dots in the same cell (centre to centre) 2.3mm to
2.5mm
Distance between corresponding dots in adjacent cells (centre to centre)
6.1mm to 7.6mm
Distance between corresponding dots from one cell to the cell directly below
(centre to centre) 10.0mm to 10.1mm
Braille should be located directly below or adjacent to the corresponding print
and separated from it by at least 5mm. If the text is on multiple lines, the braille
equivalent should be placed below the entire print text. Braille should be separated
by 10mm from any other tactile characters.
Measured from the baseline of the braille text, braille should be located a minimum
of 1015mm and a max