Tuesday, 22 March 2016

Trains, large trucks and buses and where they fit in Sustainable Safety

As a slight side break from my Sustainable Safety series, one thing that I didn't cover in my homogeneity segment was that of trains, trucks and buses, at least not in the detail that I wanted to cover. So let's do that now.

Trains are large and heavy objects that when allowed to, can move at very high speeds. Freight trains usually can go up to 70 mph (for some reason the railways in Canada also haven't moved on from mph) or 110 km/h. The Netherlands a while ago built a 120 km/h railway reserved for freight, complete with electrification, double tracking and no level crossings. Much faster than speed limits trucks often have, in Canada and the US this is often around 100 or 105 km/h, or 60-65 mph, and in Europe, trucks over 7.5 metric tonnes are often limited to 80 km/h.

But this blog post is about road safety of course, and at an at grade level crossings, if a train hits anything, there is going to be a big problem. If the vehicle is large enough then it might derail the train too. Many campaigns about road safety often cover level crossings. But as usual, without a natural reason to stop, people often take risks. By removing as many at grave level crossings as possible, there is no crossing to be risky, and provided that there is a fence on either side of the track (s), then it is very unlikely that there is going to be a crash. If you can't grade separate, then the next best option is to fully protect the crossing with flashing lights, bells, and quad gates that also block off the cycle path and pedestrian crossing if they are present, and that they lock into some sort of slot and is designed to withstand a car crashing into it. Adding a bend in the road to require slowing down for this also helps, especially in letting people know where the crossing is after a long section of ordinarily straight road.

This also has the advantage in that you are able to let trains go faster if they are prevented from doing so only by having unprotected level crossings. In the US you can go up to 110 mph (180 km/h) just by having the gate arms, bells and flashing lights (as well as the right signal protection), and up to 125 mph (200 km/h) with impenetrable barriers.

Some advantages of trains is that they don't induce demand for motor vehicles like roadway upgrades tend to. They are also easier to make automatic, and in fact, many trains (although as far as I know, only passenger trains) are automatic. Ever ridden Vancouver's Skytrain? And even if not fully automated, they can have many systems to make them run with minimal driver input, and also far smaller risks. China uses this a lot on their bullet trains. And you need less width for a double tracked railway than for a 4 lane motorway, and with a smaller impact. You can also make them run on electricity more effectively, as batteries are still fairly inefficient, at most giving you back 2/3 the power you put in. You can also run trains further into the city centres than you can with motorways and main arterial roads.

Trucks as identified in Sustainable Safety are not able to be used to fully meet the homogeneity standards unless and until these large trucks only take on the role of being used on the through trunk roads that are grade separated with a head on crash barrier if they are over about 7.5 tonnes in mass. And you can do even better by not having commercial vehicles over 3.5 tonnes used on urban streets. The main semi trailer trucks, and others over 3.5 tonnes, would turn off of the motorway almost immediately into a distribution centre, then distribute the cargo into vans and other light trucks to take the goods around the city. This also has the advantage in that intersections can be smaller, down to the size of buses and firetrucks as opposed to long semi trailers.

Buses also have certain similar problems. They are large, often around 12 tonnes for a non articulated vehicle, but at least they don't go as fast as a truck does on a freeway. But the best solution by Sustainable Safety's standard is to separate them just like cyclists are from motor traffic, but in this case, this is because otherwise they would be a danger to the other road users, not that they are vulnerable. Simultaneously this also preforms many functions that is asked of transit, to be reliable and fast and especially avoids congestion.

The next best option is to route them on distributor roads where the most vulnerable road users are separated in space, including at intersections, and time, at any remaining traffic lights, and to provide them with stopping bays at their stops, so as to not be a solid object that can be hit from behind. They should also make as few turns as possible, so as to help make their movements predictable and minimize the risk of a conflict in direction.

A few other things that can be modified in the realm of vehicle design includes skirt guards, so that other road users and vehicles can't as easily get dragged under, better cameras to cover more blind spots can really be an improvement. There are experiments going on to see how feasible systems to make it so that you can see ahead of a truck if you are behind the truck, useful for certain undivided highways where it could be dangerous to overtake. Trucks could get some elements of automation, at least on motorways and other through roads, as truck drivers often get sleepy due to tight schedules and long drives, and given that your primary job on such a road is primarily driving in a straight line at a speed of 100 km/h for the most part, that is a fairly simple thing for a computer to do.

Some vehicle regulations I propose mainly involve rest breaks. Combined with motorway and autoweg service stations and rest stops every 50 km to take a break, it would be easier to take the legally required breaks with less disruption to timetables. But another law is needed to make it would better. You must be given specific allotted times for breaks and that you are not allowed to arrive before the time is up, and no importer or the person paying the trucker can create any financial incentives in any way to avoid such rest breaks or create a program to that effect.

Large vehicles can be incorporated into the latest and best design standards and safety models, but it requires careful use of controls over routing, size and speed of vehicles, and by separating them from the other types of road users that are more vulnerable and do not match as much as possible. The Dutch still have plenty of commercial deliveries and large trucks, so opponents claiming that buses and trucks will suffer too much do not have a foundation on which to stand, and these improvements to roadway design, vehicle design, education and rules and regulations have saved many lives over the last 24 years since Sustainable Safety has been introduced and for 11 years since it was expanded. It works. Let's adopt it, also for large vehicles and train level crossings.

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