Teaching Students to Assess Safety for Crossing Streets Which Have No Traffic Control
Dr. Mary-Maureen Snook Hill and Dona Sauerburger
1996 -- International Mobility Conference No. 8
Tambartun National Centre, Melhus, Norway

Click here for problem #1 -- certainty of observing the "worst cars"
Click here for problem #2 -- improving ability to determine safety

This paper will address the issue of crossing streets where there is no traffic control -- that is, where there is no control signal or stop sign for traffic on the street being crossed.

To cross these streets safely without relying on drivers to stop and avoid you, there must be two conditions:

Our students need to recognize those situations in which one or both of these conditions are not present, because in those situations there is considerable risk in crossing. That is, they need to know when the traffic is too busy, and they also need to know when they can't see or hear the approaching traffic well enough to know when it's clear to cross.

Seven years ago, the second author developed techniques for assessing condition #2. One technique, the Timing Method for Assessing the Speed and Distance of Vehicles (TMASD), is used to provide students with feedback to assess and develop their ability to judge when the traffic is far enough or slow enough to allow them to cross. This procedure is easy to use, and is described in Sauerburger (1989 and 1995) but time will not permit us to explain it in this session.

The other technique, called the Timing Method for Assessing the Detection of Vehicles (TMAD), is designed to assess whether or not a person can hear or see vehicles well enough to know when it's clear to cross. he steps for this method are listed at the end of the paper.

One question which needs to be answered is how we can know whether we have observed one of the "worst cars." That is, in a given situation, after we have observed a number of approaching vehicles, we need to know whether there could be any other vehicles in that situation which cannot be heard or seen as well as the ones we already observed and, if there are, whether those "worst cars" can still be detected with enough warning. This is an important issue because some people feel that it is not possible to ever observe enough vehicles to draw conclusions about any situation (Bennett, 1991).

When Sauerburger first developed the TMAD, she thought it could be used by blind people and O&M instructors to assess the safety of crossing streets which are questionable. However, we cannot judge any street or intersection as being safe or unsafe to cross, because the situation may change from day to day and even moment to moment. Sounds can be affected by snow, wet pavement, the temperature of the air, masking noises and objects that block the sound, head colds, clogged ears, hats, and so forth, and vision can be affected by various lighting situations, such as glare, and light that is too bright or dim. Because these various conditions can affect the ability of students to detect the traffic, the students must be able to assess the situation each time they consider crossing, rather than assess particular intersections. For example, if the student plans to cross a familiar street where he normally can hear the traffic with enough warning but the sound of the traffic is now blocked by a parked truck or masked by a distant lawnmower, the student must be able to judge whether the traffic can still be heard well enough in those new conditions.

Thus it is important that our students be able to routinely and accurately recognize whether they can detect traffic well enough to know when it's safe to cross. A proposed procedure to provide feedback with the TMAD to assess and improve the ability of students to make this judgment is outlined at the end of the paper.

Although Sauerburger (1995) had noted some success with using this procedure with the TMAD to illustrate the safety issue to students at uncontrolled street crossings, it remains to be determined whether the TMAD can provide accurate information about the limit of the students' ability to detect vehicles, and whether use of the TMAD increases the accuracy of students' judgments of their own ability to detect traffic under any given conditions.

Thus a study was conducted in 1995 by the Orientation and Mobility Department of Peabody College. One objective of this study was to determine how one could ascertain the limit of students' ability to detect vehicles in a given situation (that is how one could be relatively certain of having observed and evaluated the students' detection of one of the "worst cars"). Another objective was to see if using the TMAD to provide feedback to students would be effective in increasing their ability to determine their relative safety in crossing streets.

Problem #1:

Objective #1: To determine how we can be relatively certain we observe the detection of one of the "worst cars" when using the Timing Method for Assessing the Detection of Traffic.

Discussion:

Problem #2:

Objective #2: To determine whether the "Procedure to Develop Judgment of the Detection of Traffic" can help students improve their ability to determine their relative safety in crossing streets.

Discussion:

Future Directions:

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Bennett, J. (1991). The fallacy of timing methods. RE:view. Vol. 23, no. 2, 75-79.

Sauerburger, D. (1989). To cross or not to cross: Objective timing methods of assessing street crossings without traffic controls. RE:view. Vol. 21, no 3, pp. 153-161.

Sauerburger, D. (1995). Safety Awareness for Crossing Streets with No Traffic Control. Journal of Visual Impairment and Blindness. Vol. 89, No. 5, pp. 423-431.


Appendix

Return to TMAD
Return to Situations of Uncertainty for Gap Judgment
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