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Module 1: Safe and Sustainable Transportation Systems

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Pedestrian Road Safety and Associated Risk Factors

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So, uh, in this, uh, since we are only going to cover, uh, two or three lectures on safety, we are going to give you a. Uh, high level overview of, uh, what do we mean by pedestrian safety and why should it be, why you, should you be, uh, interested in providing a safe designs and safe infrastructure? Uh, what are the different risk factors involved and how you can incorporate them in your land using off-road with now, when we talk about pedestrian safety, essentially we are trying to say, is that, uh, the level of risk. That pedestrians face when attempting to walk along or cross any network of roads in our community, the level of risk that the pedestrians face. So what are the different kinds of risks that, uh, one may, uh, face, uh, it may be because of, uh, the volume of vehicles that are on the road. It may be because of the speed of vehicles that is on the road. It may be because of the condition of the vehicles. That are on the road. And it may be because of multiple other factors, uh, such as, uh, distraction while walking such as a poor road design. So there are different factors that may give rise to a risk to the pedestrian while he or she is walking along the road or crossing an intersection. So this safety is usually measured in the number of pedestrians killed or injured in collisions with motor vehicles and by public perception of risk of being hit. Maya motivated. So there are two ways. The actual is the count of the number of, uh, accidents or crashes that have happened between, uh, pedestrians and vehicles. And the second is even the perception of say, uh, unsafe, uh, intersections, right? Even if somebody, uh, there are no actual accidents that have happened, but if the pedestrians perceives that this location is dangerous for him or her, he or she may not be, uh, willing to walk on that road. Right. So there are two ways to look at safety and Breslin safety can be then enhanced by a variety of facility improvements such as traffic, calming strategies, uh, education, uh, and enforcement efforts. So this, this is a very, very broad understanding of what pedestrian safety means. Uh, and we'll be taking most of the materials on pedestrian safety from the who world health organizations, but it's in safety manual that has been developed. So. Uh, even the health organization, world health organization is looking at safety as a pedestrian safety as a health risk, right. Uh, because of the severity of the injuries that are involved. Uh, the other aspect that is also included, uh, when we talk about petition safeties, pedestrian security. So all those two have a slight difference in their meaning. Uh, when we say personal security, what we mean is the, uh, is the risk of becoming a victim of a violent crime while you're walking, right? Violent crime includes assault, robbery. Uh, rape or even a murder against pedestrians. So what happens is when you are walking, uh, you may be, uh, a, is a risk of being hit by a vehicle, but BS, you may be robbed, uh, is the risk of being robbing a risk of, uh, other kinds of assault while you're walking. Because while you are walking, you are almost, uh, you're vulnerable to the entire environment around you, right? Uh, while you're driving a motor vehicle, especially a car, you are. I surrounded by the environment within the car. Um, even in two Wheeler, you have the ability to speed away from the situation. Whereas when you are a pedestrian, uh, you are usually a vulnerable road user, and you may be vulnerable to different forms. Of, uh, assault. So that is the aspect that security deals with right. And safety deals with them, uh, accident, uh, off the disc. Uh, so security can be enhanced with the provision of street lighting, uh, increased police enforcements, all the CCTV cameras that have now installed, uh, many, all of these, uh, gives a rise to it, improved sense of security amongst the pedestrians. So why should you be looking at, uh, pedestrian safety? Right? What is the, is it, is it a big cause of concern? Um, do hardly, uh, what are the numbers when you talk about, uh, pedestrian accidents, uh, so on and so forth. So if you. If you look at the numbers by itself, you know, that safety, uh, along our roads is a major issue. Uh, we almost lose 400 lives on Indian roads every day on an average. So on an average every day, Uh, an equal and tough, uh, Boeing plane crash happens on our roads, but, uh, unfortunately, uh, not a lot of effort as being or not, uh, that degree of effort is being put into reducing this accidents. Uh, so when you look at all from among all the traffic accidents that happens, uh, almost 22%, uh, of them, uh, are encountered by pedestrians, right? So almost one fifth. Of them happened with pedestrians, uh, globally about, uh, to like 73 or 75,000 were killed in traffic crashes. When we looked at, uh, all 2010 data. Right. Uh, so maybe, uh, these numbers have gone up or gone down in the last 10 years is something for us to, uh, look at. So these were the people that were killed. So actually, uh, there are the other thing in with pedestrian accidents is that many accidents go. Under reported or unreported, right? Because if it is a minor accident, uh, nobody tends to want to report that or you wouldn't report it there. They just brush, brush themselves, go out on their Merry path. So you never know how many actual accidents that happening accidents that are reported only, almost. Uh, when there is a grievous injury or there is a fatality or Soren and so forth. So when we talk about the people killed is to like 73, the actual number of accidents will be much higher, uh, that the pedestrians and counter. So this is a very, very, uh, serious, uh, uh, cause of concern for all of us. Uh, Arpan uh, transport, uh, professionals. Uh, so this is what actually the fatalities might be, uh, actually the number of crashes, maybe much higher than just the fatalities. So when we are looking at what are the key factors that influence the risk of pedestrian traffic injury, uh, worldwide, it has been seen that speed is one of the most key factors. Speed of vehicles. We mean speed of vehicles is on there. The foremost factor that that increases the risk of pedestrian traffic injury. The next is, uh, driving under the influence of alcohol, right? That is one of the, another, the second most key element or the second key element in, uh, in, uh, increasing the risk of traffic into this second is the lack of actual pedestrian facilities in, in themselves. The fourth one is the inadequate visibility of the pedestrians support design of the roads is something, uh, or design of the roads. And also, uh, just poor lighting, uh, and poor, uh, gear that people wear, uh, is, is as a cause of, uh, uh, traffic injuries. And finally inadequate enforcement of traffic laws may also lead to a higher risk of. But Austin traffic injuries. So when we look at the aspect of speed, what has been noticed is that the speed at which a car is traveling influences both the crash risk and the crash consequences. So the speed determines not only the risk of a crash, but also what happens if you. Art involved in that accident. So what, uh, uh, usually this, what this chart says is that if the speed happens, uh, if the crash happens at a lower speed, right? The probability of the pedestrians, um, succumbing to the injuries is very low. Actually, if somebody is traveling at 10 miles per hour and hits a pedestrian, so the probability that he or she will, uh, Would pass away as a result of that injury is even less than 10%. Right. But what happens is that it exponentially increases beyond 20 miles per hour. So if, if you're hit by a vehicle at 20 miles per hour, you are, you are still, your risk of death is still very low. However, just to 10 miles per hour increase, your probability of dying goes up almost by 40%. Right. So there's a four times increase in your probability of death while you are a pedestrian. If you are hit by a vehicle that is moving at 30 miles per hour as compared to 20 miles per hour. So this is what every pedestrian and every motorist has to be aware of it. 30 miles per hour even does not seem very high. Right. But if you are traveling, even at that speed, Your probability, if you hit a pedestrian, their probability of a dying is very, very high, almost 40%. So you have to be very careful when you're driving on the roads. You have to always keep in mind that the road is not only for motorized vehicles. The road is for all users road is for, but Estrin road is for a bicyclist road is for different types of non-motorized. Users as well. So that is the training or that is the behavioral change that all the motorists have to bring in themselves. The major cause for these crashes is that the pedestrian misjudges the speed of the vehicle that is coming towards him or her, right? Because of the lack of judgment of the speed, he, or she might want to cross the road right in front of that. Uh, speeding vehicle. So that will always cause it, uh, uh, cause of accident is, uh, always higher because of the misjudgment of the speed. So hence speed management is an important, uh, uh, issue of addresses around the world when it comes to pedestrian safety, speed management includes several design factors, uh, several, uh, um, education factors that are involved in. Uh, education and enforcement factors that are involved in managing this speed of, uh, this is another, uh, another, uh, chart, which, uh, tries to explain the stopping distance, how a pedestrian, uh, our, uh, motor vehicle can break, um, uh, depending upon what speed he or she is traveling it. So if somebody is traveling at 40 kilometers per hour, uh, he, or she can break within. 26 or 27 meters, uh, from where, from the, uh, point where he or she is. Whereas if the speed increases and somebody is traveling at 50 miles, 50 kilometers per hour, that stopping distance increases by almost 10 meters. So, uh, the slower you travel, the lesser of the chances that, uh, are, uh, higher, the chances that you'll be able to break. Before a pedestrian, if you encounter a pedestrian suddenly and also, uh, lower the chances that an accident will happen. So always, always, uh, drive at a speed that is either posted on the, uh, on the road or even sometimes drive at to speed lower than the once that is posted. Especially if the environment, uh, has a lot of pedestrians and bicyclists in the. Uh, the stopping distance, uh, uh, is simply given by a farmer that everybody, whoever has taken, uh, a traffic engineering course in their undergraduate or undergraduate level, uh, understands this, the stopping distance is directly related to the speed at which, uh, the vehicle is moving. Uh, and it's given by the formula, uh, velocity square bike. Divided by two Muji where music coefficient of friction and GSD acceleration to do that. So if Amy, a driver in a car on a residential street is traveling at 50 kilometers per hour and she puts on a break when she sees a stop sign. The caution of friction between the tires and road is 0.6. What is the stopping business of the car? Right. So she sees a stop sign. Where say, for example, a pedestrian is waiting to cross. Uh, now she's traveling at a very, uh, high speed, uh, this kind of question of friction, how much distance will it be before she's able to bring her car to her full stop? Right? So if you just convert this into meter per second and put it into this formula, so you will see that. Uh, 16.4 meters is the required distance. So if he, uh, uh, Amy is, uh, already, uh, too close to the stop side, she may not be able to stop the car in time before the stop site. So that is what is very, very important. When you are even designing your crosswalks, especially at a mid-block audit on signalized intersections, you have to be very, you know, to make sure that there is enough stopping sight distance. For the motorized vehicles. So, uh, warning signs have to be put up much in advance of the intersections so that, uh, vehicles can slow down and stop and allow the non-motorized, uh, pedestrians or bicyclists to across the board. Uh, the second, uh, uh, most, uh, important element in any pedestrian safety related, uh, issue is the presence of alcohol. Uh, in the blood content, uh, of the motor vehicle list that is involved in the accident, what happens is, uh, impairment by alcohol, uh, increases both the risk of the road, traffic crash, as well as the severity and the outcome of the injuries. Just as speed. Uh, when does both, the occurrence of the accident is also increased as well as the severity or outcome of the accident also increases, or is also dependent upon. Whether or not the person is under the influence of alcohol or not. Uh, alcohol consumption, uh, reduces, uh, art gives us to poor judgment, increases the reaction time and lowers the vigilance and decreases visual equity. So this is something that transportation engineers always harp upon saying that it increases the reaction time of the. Motor lists or the, uh, motorist other driver, right? You may be able to react very quickly if you are, uh, normally driving. Whereas if you are driving under the influence of alcohol, you may not be able to react quickly to the situation, but a pedestrian comes in front of you and hence will not be able to apply brakes or maneuver God around, uh, around the pedestrian or the bicyclist. Uh, alcohol consumption is also associated with excessive speed. Uh, the alcohol impairment is a risk, not limited to the drivers of the vehicles, but it's also an important for the pedestrians, right? I mean, even pedestrian should be aware of the environment while they are walking. If they have, uh, consumed alcohol and should not always be blaming it on the motorcyclists, but Destin should also be very careful while crossing. Uh, while crossing the road, for example, uh, if he or she has consumed alcohol. So, uh, alcohol consumption is, uh, alcohol consumption related, uh, pedestrian accidents are growing, uh, over the years. And this is a cause of concern for many, uh, for many enforcement agencies, as well as, uh, urban local bodies and a strict vigilance is, uh, nowadays in place a law, uh, around certain areas where. Uh, usually people do consume alcohol and then try to travel, uh, and that is completely discouraged. Uh, the other part of course, is the, uh, even lack of pedestrian facilities, uh, and poor land use planning as well. Right. Uh, you may often encounter, uh, for example, a school, uh, right alongside a high-speed or, uh, road. Right. A high-speed, um, national highway or an expressway, uh, suddenly, uh, approaches, uh, certainly Caesar school, right alongside with, uh, alongside the road. And, uh, this school has an approach road where a lot of young children are either waiting to get on the bus or trying to cross the road, which creates a complete. Uh, unsafe situation for all of those children or any pedestrian for that matter. So, uh, land use planning, uh, when it comes to providing safe, uh, uh, pedestrian or non non-motorized infrastructure is very, very, uh, important and also providing the proper types of, uh, pedestrian facilities in the roadway design. Right? If it is a, if there is an intersection that has, uh, Two or more lanes, uh, then you have to provide a few Jaylin, for example. So we have already looked at, uh, you've already looked at, uh, such design principles when we, uh, when we were discussing the, uh, an empty modules. So a lack of proper pedestrian facilities is also a concern when it comes to, uh, pedestrian safety, inadequate visibility of pedestrians is an issue. So at night you are always recommended to wear something. Uh, that is, uh, that reflects, uh, that is translucent, right? Uh, otherwise, uh, you may not be, uh, visible to the, an oncoming, um, uh, motivate list, uh, especially the various not Valley very well lit, right? If the various welded, uh, it is a different issue. So there are maybe two issues involved here. If the area has to be also well lit and also the type of clothes that you wear at night, uh, should also be something, uh, that is, uh, retro reflective. Uh, in nature and allows a greater safety who the pedestrians, uh, other factors, uh, other new ways factors. Uh, what, uh, we have noticed in current research is that, uh, uh, when Paris, when motivate lists, drive their vehicles with their mobile phone in a switch off or switch off mode or in a. Uh, do not disturb mode. Most of the drivers do feel that, uh, it has made them, uh, into converted them into safe drivers. Right? So the use of mobile phones while driving, uh, is, uh, is prohibited in many of the, uh, metropolitan areas even in, uh, in India as well. Uh, so as the next time, uh, you are driving a motor vehicle and uh, Oh, your phone rings. Uh, kindly do not attend to it while you are driving, uh, uh, either hybrid on a, do not disturb mode or just let it ring and you can pick it up once you park your vehicle. So, uh, these are something, some things, uh, that are education related, uh, uh, that have to be, uh, people, drivers have to be aware of it. Uh, uh, now, now that you know that, uh, the risk of a pedestrian injury goes up. Uh, 40% almost when your speed goes up to 30 miles per hour, you should not, uh, be talking on the mobile phone or, uh, any such any other forms of distraction while you're driving, uh, should not be, uh, uh, entertained. So as to, uh, improve the, uh, uh, improve the safety conditions of better students. Uh, driver fatigue is a very important thing there, especially we noticed this among, uh, truck drivers who drive for a longer period of time. Uh, so there is always, uh, a relaxation time built into their schedules so that they do not drive more than eight hours a day or so, because, uh, due to fatigue again, your reaction time increases and you are not able to, um, react in time. Uh, to, uh, about, uh, a dangerous situation, um, uh, reduced actual time inability of children to gateway clear speed and other relevant information. You have to be very careful when you're dealing with children and elderly people on the streets. Uh, you have to, uh, it is always safe to accompany them with some adults so that, uh, safety is enhanced. Uh, the others include failures of drivers to respect pedestrian. Right-of-ways always, always, uh, stop at the stoplight. We have this bad, uh, bad behavior of always taking our vehicles a few meters beyond the stops, stop sign, or stop line, and then stopping. And, uh, some of us also do not stop. If, for example, there is no cop around in that. Uh, intersection. So all such behavior has to be, uh, strictly, uh, avoided, or you have to stop before the stop sign, uh, allow the pedestrians to cross at the bicyclist to cross, and then only. Um, uh, cross the intersection, uh, once the signal is green. So we also have this tendency of trying to, uh, start or charge or start moving ahead of the, uh, stop line. As you see the countdown clock going, counting down towards zero. Right. Do not do that. Have some, always have patients while you're driving, because. Uh, safety's, uh, uh, of paramount interest, uh, uh, the other, uh, newer phenomenon that we are noticing is that some quieter vehicles, uh, are, uh, causing, uh, a little bit of a conflict, uh, because of, uh, because people are not able to hear them, especially in low volume roads, where there are not many vehicles and pedestrians may not be able to detect them. I heard of time because they're so quiet, but that is, uh, something, uh, of a newer phenomenon that is happening. Uh, the other design contributors to pedestrian injury includes traffic mix. So if there is high mix of trucks or heavy vehicles on the street, that does increase the risk to pedestrians, uh, the width of roads and lanes and. Speed. We have already looked at, uh, that's why, uh, one of the traffic calming measures is always to narrow the lane width. So you will see that narrowing the lane, which usually reduces the speed of the vehicles that comes the traffic down. And it helps, uh, uh, promote, uh, a CFPR from non-motorized as well as pedestrian users. Yeah. Crossings, pedestrian crossings are, uh, almost always, uh, uh, not very well designed. Uh, the stopping sight distances are not. Um, I provided, um, also when the refuge islands are needed, there are no refugee islands there for pedestrians to safely cross. So those design parameters also cause, uh, uh, our contributor to pedestrian injury, uh, high volumes of traffic is also a contributor and just the perception of safety and security of the travel environment. Causes that issue as well, perception of safety, uh, is always, uh, how do you make a person? Uh, maybe all the design parameters are pretty good, but, uh, pedestrian still feels that, uh, it is unsafe. Uh, it is still, uh, the perceive that that intersection is unsafe. So how do you deal with that kind of a situation? Right? Oh, land use planning, always population density is, uh, The frequency of pedestrian crashes is strongly influenced by the density of the resident population. Right? If there is lot of pedestrian activity going on, usually you will see that, uh, uh, the streets have lower, lower traffic speed and the pedestrian, uh, related traffic crashes up lower, uh, such kind of, uh, so, uh, one thing that we always, uh, complain about is. Uh, that is, uh, uh, too much congestion in our streets, but the brighter side, if you want to look at it, is that, uh, due to this congestion, the speeds are so low that, uh, the possibility of, uh, uh, grievous injury is very, very. Less. So that is, it's not an ideal situation, but at least, uh, safety wise, uh, um, it is not happening.

Uh, it is not happening pedestrian safety. Uh, so we have to, so in other words, when you're trying to, uh, design for a safe road, it is always, uh, look at it from the point of view of the vulnerable road user, not from the point of view of how to make the road safer for the vehicles, uh, right. The vehicles. Uh, our safe, uh, are the vehicle motorists are already safe because they are in an enclosed environment in the car or, uh, in their tubulars. But, uh, a vulnerable road user, uh, is one that is the most unsafe on the road. And you have to think about, uh, from the point of view of the vulnerable road user, when you're trying to designer see fruit, a mix of land uses will allow more pedestrian activity again and more pedestrian activity for shorter trips. Again, makes us treat, uh, automatically calmer, reduces the speed of the motor vehicles. Uh, similarly, the city structure, if your city is, uh, very compact and dense, uh, then you would have your land users very close to each other, and that would encourage a lot of people to. Walk and if, uh, the volume of pedestrians walking increases again, uh, the motorized, uh, uh, speed of motorized vehicles reduces. So a compact city usually is a very safe city. Whereas if you have a city that has broad. Uh, and, uh, uh, sprawled city with wider traffic lanes, high volume, high speed lanes usually, uh, causes a lot of, uh, uh, uh, traffic safety issues or pedestrian safety issues. Right? So the city structure also, uh, also, uh, determines, uh, how safe, uh, pedestrian fields along their streets. Uh, one way to determine, uh, the land use mix. Uh, in your city is the, uh, entropy index, uh, higher. The entropy index means higher, uh, land use mix and higher land use mix, meaning, uh, better for safety, right? So entropy, the entropy index is nothing but, uh, the different types of, uh, land use. Uh, it, it, it develops an index to determine, or the different types of land use, uh, on, on the different types of parcels. Right. So, for example, if you were, uh, if, uh, if you were to be asked to, uh, develop a entropy index for this kind of a land use distribution, where there are four different types of land uses, uh, water, agriculture, residential, and industrial, uh, and you have different parcels, you have 12 parcels of water, 18 parcels of eight parcels of agriculture, six of residential and eight of industrial. So for this entire, uh, uh, land use mix, your, uh, entropy index. Wouldn't, it would be nothing but a summation of the probability that one, a one cell is a particular type of land use, right? PJ, the probability of that cell being the type of land use of J uh, times, uh, uh, the log of that probability divided by. The log off and the natural log of all of the different types of land uses. So in this case, uh, Jay's four. So you divide everything by natural log of four. And the probability that, uh, uh, one of the cells is water is 12 divided by 36, right? Because there are 12 different types of, uh, other 12, uh, Waterland uses. The total is 12 plus eight plus six plus eight. So the total is statistics. So 12 by 36 gives us the probability, uh, 0.3, three in LA. And that's a log of that. Probability is minus point a 1.1. If you submit to all different types of four different types of land uses divided by the natural log, you will get a, uh, entropy index of 0.94. So as the entropy index, uh, It is closer to one. You would tend to say that there's a good mix of different types of land uses and a better mix of land uses. Usually in sheriffs, that there is higher walkability and because land use is being close to each other, makes people more probable to walking.