Episode 20: How to Fix the Bus

Buses are an inexpensive and easy-to-deploy form of mass transit that could help reduce traffic congestion and curb air pollution. But in the United States, no one wants to ride them—and for good reason: the design of the American bus has not changed much since World War II. The antiquated design is uncomfortable and creates hazards for riders, drivers, and pedestrians. How could the bus be transformed into a mode of transit that people actually want to use?

On this episode, host Lisa Margonelli talks to Brian Sherlock, a former Seattle bus driver and safety specialist at Amalgamated Transit Union International, the largest public transit union in North America. He explains what’s wrong with American buses, and how a redesign could make for a better urban future. 

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Lisa Margonelli: Welcome to The Ongoing Transformation, a podcast from Issues in Science and Technology. Issues is a quarterly journal published by the National Academies of Sciences, Engineering, and Medicine and Arizona State University. Most of us have ridden a bus, but in America, few of us love the bus. American bus service is inconvenient and unreliable, and the bus designs are outdated. They’re uncomfortable for passengers to ride, difficult for bus operators to drive, and a safety risk for those inside and outside of them.

But things could be really different. Better designed buses could change the transit system for millions of Americans. I’m Lisa Margonelli, editor-in-chief of Issues. I’m joined by Brian Sherlock, a safety specialist at Amalgamated Transit Union International, one of the largest transit unions in North America. Brian specializes in transit health and safety issues. He’s a former Seattle bus driver and has spent many years thinking about how we create the bus of the future.

Brian, welcome. I’m very excited to talk to you about your long experience understanding how buses work. Welcome.

Brian Sherlock: Well, thank you. I really appreciate the opportunity to discuss some of the things we can bring to writers and employees in transit.

Margonelli: Before we talk about the bus of the future, let’s talk about the bus of the past. What’s it like to drive a bus?

Sherlock: Well, it was a lot of fun. I’m very social and it was a way to get paid to chat with folks, so I just had a grand time in that regard. Physically, it really beats you up, and the high control efforts and extremely high whole-body vibration. The suspension was designed for military vehicles in World War II, remarkably, and so it’s not designed to provide a smooth ride, and there’s just no excuse for it remaining in there except tradition. And then the driver is sitting out ahead of the front wheels. So any impulse coming into the front wheels gets amplified by the time it gets to the operator. Then the seats, they look like they should be a good idea. They go up and down with motion of the bus, they’re suspended. But unfortunately what they end up doing is turning one pulse into many because they’re not critically damped. They don’t go up and down and stop. They ring. So one impulse gets turned into many.

Margonelli: So can I just say—so the driver on the bus really does go up and down the whole way. The driver is going up and down and gripping onto the steering wheel, which is fixed.

Sherlock: Fixed, but bounces around a lot. And that creates hand arm vibration syndrome, carpal tunnel, a whole lot of these things. Basically every segment of your body gets pretty thoroughly beat up.

Margonelli: So the bus drivers are getting worn out physically from this up and down and the carpal tunnel and all of these other things. And what else is going on?

Sherlock: A quick note on the physical stressors. We did a number of surveys, standard ergonomic surveys, and we found that for one example, 42% of all bus drivers are unable to make it to work in a given 12-month period because of low back and across all the other body segments, it was roughly a third, with over half having multiple issues that kept them physically unable to make it to work in a given 12-month period. So it’s pretty staggering levels of abuse of the body.

But getting back to your question about the other things going on, you’re in a nearly constant state of cognitive overload. You’re supposed to keep track of everything that’s behind the bus, in front of the bus, inside the bus, and you just don’t have 17 eyeballs to keep track of all this stuff. And the mirrors are primitive, and the sight lines are terrible. The structure of the bus has been built as absolutely cheaply as possible, and that results in enormous blind spots and a lot of pedestrian fatalities, or an unnecessary number.

Margonelli: So one of the things that started to happen when COVID first appeared in 2020 was that there were very high rates of infection for some bus drivers and transit drivers. What did you know about the activity of the virus in the buses from your experience as a driver?

Sherlock: Boy, this isn’t a pretty picture. I knew that airflows, again, because of being built down to the lowest possible cost, there are airflow problems in buses at the front. The front is very, very square and that causes the airflow to separate as it approaches the front. It gets too much momentum to turn the sharp corners. And so you get a low pressure zone just behind the front, all the way around the bus. This takes the air on the inside from back to front where it exits through large leakage paths near the operator. So I knew that SARS was coming our way. I was watching it in China and knew that the death rates and all that were pretty scary. And I knew that if anyone on board was shedding virus that would exit past the operator making it one of the worst places to be, save a COVID ward.

Margonelli: So the viruses are coming forward. You already were prepared for this because there is a connection between driving transit and getting viruses anyway. So tell us about the levels of COPD and other respiratory illnesses among drivers even before COVID hit.

Sherlock: Yeah, COPD is a good example. If you take all transit workers, not just operators, had over 80% higher rates of COPD than the rest of the population. And you can hear it in the voices of senior operators and that sort of thing. Because of this low pressure, they hoover up some of their own exhaust and dust and debris off the street and all the respiratory infections are coming your way if you’re driving a bus. So the challenge was how do we keep folks from dying at extraordinary rates?

Margonelli: So this is as SARS started coming towards us, as COVID started coming. What was the first reaction that you had?

Sherlock: First was panic, and I just laid out on the couch to think about it, determined to come up with some kind of an answer. And what I came up with was, of course, masking, but there was a shortage of masks that were effective. And so we came up with a solution where there is fresh air available on the front in most buses, and we could use the fresh air that comes in through the front heater defroster, where you’ve got a knob like in a car that goes fresh and recirculate. So we could put that on fresh and then we could do anything, hang a shower curtain up there and create a bubble around the operator of fresh air. And it’s called positive pressure isolation, but it could be really quite crude and leak a lot.

And that was actually a design objective because the passengers need fresh air too, to dilute the gradual rise in viral titers. You know, how many virus particles there per cubic meter. And so our objective was to take care of the passengers as well, and this was the best thing we could do. And it creates all kinds of other problems. You can’t see well through a shower curtain, and if it’s surrounding you, you’ve got some real problems there. And operators tended to prefer to not put others at risk and instead take on that literally grave risk on themselves.

Margonelli: Before we get into the bus of the future, I think we need to just quickly discuss why it is that for 50 years bus drivers in the US have been driving the bus of the past. It’s built on this World War II chassis. Why is that?

Sherlock: It’s not that the transit industry globally hasn’t made excellent progress, but rather we have something that’s politically understandable. The Buy America standard, if you’re going to spend federal dollars on buying a bus, you’ve got to buy an American manufactured bus. But unfortunately the manufacturers have zero incentive to innovate. Each one has taken up a various segment of the market. There’s a higher price option that’s definitely a better bus, and there’s low priced option. So they’ve divided up the market and no incentive for innovation and there’s no incentive for price controls. We’re paying two and a half or more times for a bus here versus buying a much better bus in Europe where there’s more competition and more emphasis on high quality transit.

Margonelli: So what ultimately happened as the bus didn’t really improve over 50 years, and we didn’t really regulate those improvements, is that bus drivers themselves paid the price.

Sherlock: Well, the public as well. The ride’s terrible, the air quality’s terrible. We run down a lot of pedestrians and that’s completely unnecessary.

Margonelli: How did COVID affect the operators early on?

Sherlock: Yeah, there was a morbidity and mortality report issued recently that stated the exposure of transit operators was such that they were infected at 500% of the normal rate and dying at 1.8 times the normal rate. The miracle to me is that it’s that low given the airflows and all the many, many hours of exposure. It’s a tribute to how effective masks can be, even if they’re poor quality.

Margonelli: So this gave an impetus to revisit a whole question about redesigning the bus of the future, which I think had started maybe five years before COVID came. You had been talking to different groups and with federal agencies about redesigning buses. So tell us different plans or ideas that are in play for redesigning the bus and rethinking the future of the bus.

Sherlock: Well, there’s two tracks. One is the rush to battery electric, and that’s its own can of worms. And I’m a very green guy. I want to see that zero emission design work and it’s problematic right now. The other is this whole set of operational problems where you’re disabling out your best folks, your most experienced, the problem solvers.

Margonelli: The drivers, you mean?

Sherlock: Yeah, exactly. And the things like the whole-body vibration were studied in King County, that’s Seattle. They found that they were spending 12.8% of the entire budget on just low back costs.

Margonelli: Can I just back up here? So one eighth of all the fares and all of the money coming into the public transit fund in this case, is being spent on lower back injuries?

Sherlock: Correct.

Margonelli: That’s nuts.

Sherlock: A staggering number. That is absolutely nuts. And that led to a series of experiments with the University of Washington Ergonomics Department where the actual dynamics were examined. And so if you go over an expansion joint, like on an elevated portion of a freeway, in a car it’s a bump-bump and its trivial. In a bus with a brand-new seat from either of the two manufacturers that dominate the market, it’s your body weight worth of slam. So as a 200 lb person, you’re getting a 200 lb wallop, go through a good chuckle and that could be 500 pounds.

Margonelli: Wow.

Sherlock: Yeah.

Margonelli: So part of this is to really change the suspension so that you’re not slamming bus driver’s backs every day.

Sherlock: Yeah. Actually, when we got this project, the combination of direct objectives of the FTA and their broader priorities gave us an excuse to start at the front bumper and consider changes all the way to the back. And I really do mean the bumpers. They’re battering rams currently. And why can’t they be energy mitigated?

Margonelli: What does that mean? They’re a battering ram now, which means that they’re hard. So they slam into things and they slam into cars and pedestrians and people like that. So an energy mitigator is what? Something that’s foam?

Sherlock: Oh, I was actually looking at airbags for pedestrian protection. And because we do bash a fair number of pedestrians and that technology is just beginning to be brought into cars. It was one of my disappointments of the project that in the time allotted, I was unable to find an industry partner who was interested in this relatively small market of vehicles, but they’re in Volvos, for example. There’s an airbag available that mitigates frontal impacts with pedestrians. It elevates the hood right next to the windshield and cushions the blow as people are folded over by the force of the impact and slam down kind of whip-like. And so that mitigates that very hazardous portion of the duration of the impact.

Margonelli: This is really interesting because it shows that how little creativity we’ve put into thinking about the bus.

Sherlock: Bingo.

Margonelli: Because the fact that you could have, it’s blowing my mind that you could have airbags on the front of the bus to protect the pedestrians, but of course you could. And why haven’t we thought of that? So tell me some of the other things about this future bus because it’s a new world.

Sherlock: Yeah, indeed. It’s rather that around us is a new world and transit hasn’t recognized the change in the last, as you’ve been saying, half century. But there’s all the control systems are, and I do mean all, are really, really primitive right, down to the switch gear. The switch is the control things like blowers and lights and all that sort of thing. None of it’s really within ergonomic reach and the steering effort is enormous. Even with boosted steering, we still have five turns locked to lock. It varies.

Margonelli: What does five turns lock to lock mean?

Sherlock: That means turn all the way one way and now measure the amount. You go back clear to the other extreme and that’s about five, five and a half turns.

Margonelli: Wow, that’s a lot.

Sherlock: It’s ridiculous.

Margonelli: It’s a workout.

Sherlock: Yeah. And it comes from not thinking it through and is something that was necessary back when we had manual steering. I started on manual steering buses and it just has come with us all that time. So I measured, because this was just appalling and people were getting carpal tunnel, all that stuff. A number of years ago I measured the effort and on a straight route there were a couple of little turns but not much. I found that over eight hours there was 13,000 pound feet of effort required. So that’s equivalent to a hundred-pound person climbing up a rope with only their hands and going 130 feet. It’s absolutely a ridiculous in a powered control.

And so one of our objectives is to bring that down as close to one turn, lock to lock as possible. So a progressive steering where it’s very much like current on center, but the further you turn the steering wheel, the faster the road wheels turn. There’ve been cars with this feature for many, many years and it just really dramatically lowers the total effort, which is force times distance. So you’re reducing the distance. We also reduce the amount of force required. Pretty absurd levels are required to drive buses. And at the same time, one of the primary directives from the FTA was a functional security barrier.

Margonelli: Let’s just talk about what a functional security barrier is. That’s like near the fare box. When people enter on the front of the bus, they can talk to the bus driver usually, and there’s a fare box and some combination of gates and windows between them and the bus driver.

Sherlock: Yeah, ineffective ones. They’re almost none of these that work. And the reason is there’s a series of conflicting interests in the driver’s workstation. As you said, passengers are supposed to board and exit there, pay the fare there. We’ve killed a lot of pedestrians for a lot of years because the fare box was big enough to block the right half of the windshield up to its midpoint. Absolutely ridiculous. Obscene is more the term.

Margonelli: How did that kill pedestrians?

Sherlock: It blocked off your view of anyone on the right half of the windshield up to well over six feet tall. And yeah, oh my goodness. That was the predominant pedestrian accident type that was severe. That’s now with low floor buses, now the elevation of that fare box has fallen and so there’s a better view out the windshield. And so now the predominant accident type for quite a number of years has been at the left front in left turns. But back to the barrier issues, the barrier because the operator has been pushed as far forward as possible to get in as many seats as possible, which is very understandable, but it creates these secondary problems. You can’t get a barrier in to that small space and have passengers come in and out without blocking views, having masking reflections and these sorts of things. So that for example, if it’s sunset and the sun is setting to your right, the left side of the street is going to be brightly lit and the right side’s going to be in deep shadow.

Well, if you have a barrier to your right, it’s going to reflect the bright side of the street and you’re trying to look through it to the dark side of the street. And that causes what’s called a masking reflection. It’s like a one-way mirror. It’s not like you can’t see through it. It’s all based on the masking of transmitted views by reflective views, much like brightly lit fog, it doesn’t allow you to see through. If the fog wasn’t so brightly lit, you’d see through better it. It’s similar, it’s called masking.

So what operators have even demanded is that the barrier that’s there to keep them from getting killed, and I did have a friend who’s shot and killed in the driver’s seat, that’s really alarming. And so there are security barriers there, but operators request that they be cut back so that they can see the right side of the windshield and the right mirror, which is critical to not kill people outside the box. And so as a result, almost all barriers that are out there right now, an assailant can just reach right around them, especially if they’re big enough to hurt you.

Margonelli: So what is the design solution to something like that?

Sherlock: You have to end up with a little bit more room in the driver’s area. And the barrier can then go between the operator’s eyes and the pillar right ahead of the front door. And the barrier can be on axis or in plain with your eyes. So the existing pillar that’s there can have the barrier placed between it and your eyes. So it has vanishingly little impact on vision, but that does require a little bit of extra space in the front. That system works even better if you can get the barrier behind the operator because if you’re making a right turn, buses, because they’re so huge, turn very extremely sharply at the front. And so when you go make a right turn, you actually pull into the intersection to where your shoulders lined up with a curb on the street you’re going to, meaning that the lanes of the street can only be seen through the front door and a little bit of the front window.

Well, that area gets blocked by a barrier that’s between you and the door and front corner. And if again, you have this lighting situation where the area you’re trying to see is dark and the area reflected is bright, you can’t see a darn thing. And as much as I’m very aware of these issues and have studied them and photographed them to demonstrate them to others and that sort of thing, I could not reliably predict when I was going to have that problem and when I wasn’t. Part of it’s just cognitive load. And part of it’s that it’s not predictable in terms of, oh, on this trip at this time of day on this route, I always have this masking problem. The weather’s going to be different, sunrise, sunset, and all this sort of thing changes. And you don’t always drive the same thing every day necessarily.

And so you just couldn’t predict it. And boy oh boy, mid-turn, if you’re suddenly blind, you can’t just stamp the brake. You might avoid an accident in front of the bus, but you’ve just had 30 accidents inside it. So it’s fairly difficult problem and it’s because operator issues are considered last, whether that’s the interest of the operator or the cognitive and perceptual needs of the operator, they’re always put last. And so whether it’s something I really value, disabled access to the front door, equal access, not being forced to take a secondary path into the bus, that’s a huge priority. And other things take precedence, like the number of people you can get in the bus. And then we have these bad engineering decisions that result from that. And we need to think holistically about the thing, whether it’s the purchase cost being the lowest possible amount or is the real important variable, the total operational cost over the life of the vehicle. And we need to think about all of these things in terms of the economics, the service quality and the safety of the whole operation. And that just hasn’t been done.

Margonelli: And one of the things that you bring up is that the needs of the operator are often placed last. And that goes back to something that was happening back when the city buses were actually pulled by horses.

Sherlock: Yeah, it’s really a shocker and an illustrative of the problems that we still face today. In the early days of transit, street cars were pulled by horses and if you froze the horse, you had to go buy a new one and they were expensive, but you freeze the human and you just hire a new one. No harm, no foul. So we lost, even in my union, one of our first officers froze to death and the horse went back to the barn by itself to get fed, get warm. So there was quite a battle about this and some related issues that are equally primitive.

And finally in Washington DC there was the Vestibule Act and it required that there be a shelter, not heated or anything, just a shelter, a wind break for the operator. But that was a long, prolonged battle. So we faced this kind of thing for a very long time and of late we’ve been able to make the point that if we just consider the economics, the welfare of the taxpayer, the welfare of people out in front of the bus, the welfare of the riders and others, we don’t have to make an argument about ourselves and the interests that should be protected by the employer, our health and safety.

We don’t even have to bring that up in order to make tremendous progress. And I think that change in messaging has been a key element and it’s pathetic, but it’s been effective.

Margonelli: Issues as a magazine that talks continuously about innovation. And we’re sitting here and we’re talking with a lot of very sophisticated equipment around us that has all been the result of innovation. My phone is going off on the side, I’m sure yours is too. All of that is years and years of aggregations of innovations made by individuals and companies and government and DARPA and everything coming together. And yet it’s wild that the bus has not really been the site of innovation, that we could have big chunks of our lives or places where this attention of innovation has not been focused. What do you chalk that up too?

Sherlock: I’ve not explored this area as much as you might suspect. Some of the social questions are very unsettling and the transit workers and writers have been subject to some of that social disdain. And we put a lot more money into promoting the interests of billionaires than we do in promoting the interests of commuters in cities. So nonetheless, we do have an opportunity to take the innovations that have occurred in transit around the world. Like our benchmark for this design that we wanted to exceed is the best bus by all accounts, a Mercedes Citaro. It might as well be a spaceship by comparison to what we’re driving. And it costs between two and a half times and three times less than what we’re paying today, with far better outcomes for everyone involved. The riders are better cared for. People outside the vehicle are put at less risk and the economics are better. And of course the operators are far less frequently injured.

Margonelli: So let’s talk just really briefly about the ultimate space age aspect of the new bus that you’re talking about. And that is that each person would be in their own pocket of air. How does that… When I think about getting on the bus, I think of the whole bus smells the same. If someone has lunch, you can smell their lunch.

Sherlock: Yeah, let’s just hope it’s a good one. As we were working early days in the pandemic to push out these temporary barriers, after we came up with this positive pressure isolation notion that could use the front heater defroster to put a bubble air around the operator who was at greatest risk because of hours of exposure, I called up a researcher, Andrew Crum at Virginia Tech Transportation Institute, who I’d worked with before. He was an engineer and asked with would he be interested in saving a few lives, no pressure. And so he volunteered his time to pursue this and I connected with a professor of Fluid Dynamics at the University of Washington with whom I’d worked previously. And he was informing us on the airflow issues because if airflows were really counterintuitive. So after we were done with our work, he was thinking out loud and said, wouldn’t be great if we do as a clean room approach with vertical airflow? That would keep all the passengers in their own isolated column of air.

And then there’s a thump and that’s me falling out of the chair. This was just such a fabulous idea, just instead of the flow going from back to front through the length, carrying viral shedding to everyone on board potentially, why not just have it come out of the ceiling in a grid and go out under the seats in the floor? And so I thought about it for a couple of days and thought through the puzzles and realized that we really could do this.

And since the first professor doesn’t like doing computer simulations, I connected with another professor of Fluid Dynamics at UMass Amherst who had done fabulous work in vehicles. And same thing, would you love to save a few lives and chuckle, but it’s not funny. It’s real serious business. And so he modeled this concept and it turned out this thing worked like mad because there’s an unobstructed path from the ceiling to where you breathe, meaning that you can maintain a orderly flow vertically with very, very small amounts of turbulence.

So there’s no current to carry these viral or bacterial particles which don’t have wings or tails to fly or swim to you. So they are forced to go from wherever you’re shedding down to the floor and out. So within the union that I worked for, Nominated Transit Union International and this Bus of the Future Project together provided seed grant funding to do a second stage, much more accurate simulation at UMass. And that too showed that the concept works.

And so then the National Academies of Science responded to a proposal that the first professor and I put in for research on this, and they had what’s called an insight event. And that’s where you collect the best and brightest in a given area. And this group went through all of the concerns surrounding COVID and transit and ended up recommending the pursuit of this approach. And the FTA, the Federal Transit Administration is interested in going further down this road for all the reasons you’ve mentioned, whether it’s flu season or the next SARS or whatever.

Margonelli: And it also could help with wildfires and other sorts of pollution that are now a big part of the urban and bus air scape, I guess.

Sherlock: Boy oh boy, you just nailed it. And the zoonotic diseases are increasing on an exponential pace. It’s really fairly alarming. There’s good research available on that. And as you mentioned, the wildfire smoke. What a shocker. We really need to find some solutions here and with this approach and some good filters, which are something that’s foreign to transit, they’ve only put on filters that protect the hardware, not the people, really it’s kind of an obscenity. We really could be perceived as a breath of fresh air coming down the road as opposed to how we’re perceived now.

Margonelli: I think that’s really interesting. And so if you could come back in 50 years, can you give me just a really quick summary of what you imagine the innovated bus of the next 50 years could look like?

Sherlock: Well, there’s so many things that we can do. We can cut the whole body vibration for passengers by half, just by changing the suspension. We can cut it to a quarter by changing the suspension and seat for the operator and mitigate these enormous costs. If you solve the low back injuries, you can get a free fleet. It’s that bad a problem. And we could have an inviting environment. In the back of a bus it’s often a lot more conversation. Well, my intent is to provide a conversation nook so that the seating is designed to promote that.

Why shouldn’t this be a fun place where you see your acquaintances from the neighborhood and have your daily chat instead of a harsh, clattering, smelly environment that we’re getting today? It’s ridiculous. If we’re going to quit burning up the planet, we damn well have to get people back on buses. And we need to increase that number of riders and we need to make an inviting proposition. Politically it has never worked to push people into something like this. We need to draw them in and we have the engineering chops and hopefully the kindness to provide that service and mitigate the environmental hazards that are burning up the planet.

Margonelli: That is a fabulous vision. And it’s spoken like a person who drove a bus because he really liked talking to people. Buses present so many incredible opportunities for change, ranging from how the operators use them to how passengers take them to people who just passed buses on the street. To learn more about the American Bus System, read Brian Sherlock’s essay in Issues titled “COVID-19 Revealed an Invisible Hazard on American Buses.” You can find this link and more in our show notes.

Subscribe to The Ongoing Transformation wherever you get your podcasts. You can email us at [email protected] with any comments or suggestions. And if you enjoy conversations like this one, visit issues.org where you can subscribe to our magazine and find more essays.

Many, many thanks to our podcast producer, Kimberly Quach, and audio engineer, Shannon Lynch. I’m Lisa Margonelli, editor-in-chief of Issues in Science and Technology. Thank you for joining us.

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Cite this Article

“Episode 19: How Can Clinical Trials Better Reflect Society’s Diversity?” Issues in Science and Technology (October 4, 2022).