As you adapt to encroaching blindness or low vision, the choices you make whilst traveling alter to suit your circumstances. In railway stations, airports, and on street pavements, choices are made on how to progress forward towards a destination. Sometimes these choices are made easier through the use of a guiding sighted companion, through the feedback of a white sensory cane, through increasing technical gadgetry, or for some the assistance provided by a guide dog.
For most of my solo travel, I usually rely on my remaining sight, ‘blind luck’, and a white sensory cane as I bumble along. In my home village, I rarely use my cane and venture forth unaided and au naturelle. From a distance, I don’t look visually disabled, as I don’t wear dark glasses and usually, I have my false eye firmly in place. So many people are still surprised that I don’t recognise them until they stop and start speaking directly to me. Audible clues are starting to play an increasingly important role in my navigation especially when seeking to cross roads within the village, although the silent running of some electric car vehicles is an increasing risk as I step off the pavement.
Accessible Pedestrian Signals
I was recently interested in reading an article on Accessible Pedestrian Signals (APS) in the design of ‘intelligent’ cities and urban transport systems. The integration of simple and smart devices makes it easier for blind people to cross the road safely and avoid denting motorists’ front bumpers!
Reading it I realised I hadn’t stopped to consider how I had crossed streets in the past. After receiving my obligatory Tufty Club training at age six, crossing the street had become a series of subconscious actions of looking for traffic, checking the colour of traffic lights, and walking when I thought it was safe.
Note: The Tufty Club was created in the 1960s to introduce clear and simple road safety messages to children under 6. Tufty was a red squirrel character.
Yes, I had received orientation and mobility training from a local specialist provided by Lincolnshire Sensory Services when I was first registered as Severely sight impaired (SSI). I was grateful for the fact they had helped me start earlier than I needed with the sensory white cane training, but the extent of sight I had at that time had given the whole experience an air of unreality as I had yet to accept that I was now SSI (blind).
How People Who are Blind or Visually Impaired Cross Streets.
I was, therefore, fascinated to read how an APS academic considers how a blind person crosses a street. Rather than my simplistic belief that it was a quick listen-and-launch approach, we, the blind community, pass through many separate decision phases based on a vast array of auditory and sensory clues.
So be impressed. This is what your brain is factoring in:
Detecting the street
The first information needed by pedestrians who are blind is “Have I arrived at a street?” People who are blind or visually impaired use a combination of cues to recognize the street edge. These may include:
- The curb or the slope of the ramp
- Truncated dome detectable warnings, if available
- End of building line and open sound of the intersection
- Sound of traffic on the street beside them (the parallel street)
- Sound of traffic stopping on the street they are approaching (the perpendicular street)
- Presence of pedestrians
- The presence of an intersecting sidewalk
Identifying the street
The next information needed for decision-making at unfamiliar intersections is: “Which street is this?”
- This information is only occasionally provided in any accessible format.
- Pedestrians who are visually impaired develop a mental map and keep track of where they are within that map, usually by counting blocks and street crossings.
- Where necessary and available, help may be looked for by other pedestrians.
Analysing intersection geometry
The next information needed is: “What is the geometry of this intersection?” including:
- Is my destination curb straight before me, or must I angle to the left or right to reach it?
- How many streets intersect here?
- How wide is this street?
- Should I expect to meet any islands or medians as I cross this street?
- Am I standing within the crosswalk?
Analysing the traffic control system
Next, pedestrians with visual impairments need to know: “What is the type of traffic control system at this intersection?”, including:
- Is this a signalized intersection?
- Do I need to push a button to actuate the WALK interval? If so, where is the button?
- Is the button close enough to the crosswalk that I will have time to push it, position myself correctly, and reestablish my alignment facing the destination curb before the onset of the WALK interval?
- Which button controls the WALK interval for the street I want to cross?
- Does it stop traffic on one street or all traffic?
- Do cars still turn during the WALK interval?
- Is there a second button on the median or crossing island that I must push?
- Will a surge of parallel traffic tell me the WALK interval has begun? Will I be able to hear it over other concurrent traffic sounds?
.Aligning to cross
Before crossing, the pedestrian must align to cross or choose a heading for the crossing. Typical techniques for this task include maintaining the alignment used on the approach to the intersection and listening to parallel traffic through a signal cycle to confirm alignment to parallel traffic. The need to use pedestrian pushbuttons often prevents the use of parallel traffic for alignment. After pushing the button, the pedestrian must cross on the next pedestrian phase, usually the next time traffic begins moving parallel to the pedestrian’s crosswalk.
Identifying the WALK interval
After determining the geometry of the intersection, aligning to face towards the destination curb, determining that the intersection is signalized and having pushed a button, where necessary, pedestrians who are blind need to know: “When does the WALK interval begin?”
In the most common technique used for crossing at signalized intersections, pedestrians who are blind or visually impaired begin to cross the street when there is a surge of traffic on the street parallel to their direction of travel. This technique is dependent upon the presence of traffic and consistent signal phasing. Various types of phasing and intermittent or low volumes of traffic travelling parallel to the pedestrian may affect the reliability of that technique.
Maintaining crossing alignment
Once the blind pedestrian has begun to cross the street, the next question is: “Am I headed straight towards my destination curb?”
- Traffic going in the same direction on the parallel street offers helpful auditory guidance to many persons if it is present. In addition, pedestrians who are blind may use traffic waiting on the perpendicular street as a partial alignment cue.
- Turning traffic can make it difficult to hear and align with the traffic travelling straight through the intersection.
In the absence of traffic on the parallel street, pedestrians who are blind are more likely to veer toward or away from the intersection.
Conclusion
Although treated slightly tongue in cheek, I found it fascinating that a lot of this information is immediately available to visually able pedestrians, but auditory and sensory ‘workarounds’ may have to be developed by the visually impaired.
Developing a new road sense for those who experience the onset of vision impairment in later life clearly demands new skills and is another challenge to your confidence to overcome whilst travelling. We will all experience blindness differently and to different extents, so build on the foundations of any orientation and mobility training you receive and practice these cues and techniques locally. They will serve you well, but remember this whilst standing in the organised chaos of a Hanoi street – some scenarios defy academic sensibilities and add that spice to life that we all need to keep our senses sharp and our attitudes positive.
An Apology
I completely recognize the rights of whoever holds the copyright to the iconic shot of the Beatles crossing the road. I have decided to use it as it is a wonderful example of the confidence of sighted people in crossing the road against the challenges of the visually disabled in the same context. So please don’t be a (blue) meanie and send me lawyer’s letters asking me to pay a ridiculous sum in this not-for-profit context.
By Resampled from digital copy included on The Beatles USB Box Set, Fair use,
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