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Comment by the_mitsuhiko | Hacker News Reader

What many countries started doing is painting rails white. I believe that is also happening in the UK. I believe they started doing that in Italy with good results. This is what the painting process looks like in Austria in a trial project: https://youtu.be/GBMWHAkk6xM?t=52

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Here's what SBB (the Swiss train operator) says at [0], german only:

SBB will not rely on tracks painted white because

- it makes it harder to discover cracks in the tracks

- with prolonged use the effect noticeably lessens to due accumulation of dirt

- ÖBB and SBB have measured he effect at ~5°C and that's not significant enough to be worth it.

[0] https://company.sbb.ch/de/medien/dossier-medienschaffende/so...

It might be a mixed bag and presumably different operators have different results. OeBB did not decide yet on the future, smaller operators are. Italy has been painting rails white for many years (40?) and continues to do so.

From a linked page:

"We paint certain parts of the rail white so they absorb less heat – and expand less. Typically, a rail painted white is 5°C to 10°C cooler than one left unpainted."

Looks surprisingly laborious if this Twitter video is to trust: https://twitter.com/networkrail/status/1547986150723244032

You’d think they could make a robot to paint the rails but then again, the rails on the things that vehicles are supposed to be riding on!

Perhaps you could make a device that rides on one rail while painting the other one. Flip it around and do the other side when you’ve done the first pass.

The GP's video shows them using a spraying train car to do it much, much faster. It still has people riding on it and walking alongside, but sure looks more efficient.

Meanwhile, I notice that all the replies to the UK video are people complaining about the rail system reducing headcount and mocking the idea that this task could be automated.

Such automation will be banned in the UK. Painting things has to be done by hand. Union rules. No unauthorized mechanization! Spray cans are untested technology and are unsafe. Spray paint is worse for the environment and workers health. Besides, painting by hand is better for morale.

Painting will obviously have to happen at night (double pay), and is risky work (double pay again). Oh, and we can't do more than 3 hour shifts because it involves bending down. And we'll be needing a minimum crew of 8 - 1 painter, 1 safety expert, 1 signalling expert, 1 electrics expert, 1 spotter, 1 paint quality expert, a foreman to lead the team, and a union rep to check everything is done according to the book. Oh, and wherever the work is being done more than 15 minutes from a toilet, we'll need a mobile toilet booked and installed, as well as a break room. If any of those people are missing or late, we'll cancel the work and retry in 3 months.

This has been downvoted, but in my experience of 10 years of working in the UK rail industry, this is pretty much spot on.

Railroad deaths and injuries per capita are much lower than in the USA. I'd say the unions and RAIB have done a pretty good job at improving safety standards.

Ah, but railroad workers in the US are also part of a union/unions, with arguably even more rules and regulations and very averse to technological advances, since it reduces the need for manual labor. So yeah USA would have more deaths because everything is manual and archaic, whereas in the UK you have things like the DLR, it could never happen in the US.

The DLR is only automated because it's brand new. It replaced nobodies job. And even that was a real fight to get and caused lots of strikes.

Of course, but try to add an automated line to the new york subway.

TfL brought level 2 GoA to a few Tube lines. In the US newer subway systems are already at that level. DLR is GoA 3, and a few smaller lines in the US (e.g. Las Vegas Monorail, Miami's thing, pretty much all airport people movers) are Level 4.

Yes, newer ones don’t have the same problem, since they are not held back by the rules of a union. Sadly those are few and far between, and I haven’t heard of a new railroad line since the yet to be finished CHSR, though can’t blame that one on the unions.

Dude. What the fuck are you on about?

BART and Muni are both union shops. I don't know if SMART is but it postdates the HSR proposals.

As someone who lived through Muni's transition to SelTrac (the system that underpins DLR and I think some of the Tube lines) I can say the union was not the problem. The technology was unreliable and eventually abandoned by Alcatel/Thales. GoA 4 stuff is only viable along small, low ridership stretches of track. If you knock the level of automation down a peg or two it's a lot easier to scale up to busier/larger systems.

That would free the people to do the job of "conductor", "nanny", security, and cleaner to make that mess a less icky experience. Morale boost!

while this isn't without merit, I consistently see that individual workers are much more concious of quality of their work and safety/reliability of the end user than the management is.

We've had many industrial accidents, from Bhopal's disaster to Boeing Max, thousands of people died, and all of them were caused by management meddling where they shouldn't. none of them were caused by unions

> we'll be needing a minimum crew of 8 - 1 painter, 1 safety expert, 1 signalling expert, 1 electrics expert, 1 spotter, 1 paint quality expert, a foreman to lead the team, and a union rep to check everything is done according to the book.

Hah! Typical free market libertarian approach that cuts corners. You can't just go out and start painting stuff matey! What about the viability study? Someone needs to build a model of the processes, and conduct a pilot time and motion study. People won't just accept white rails without consultation. Where's the perception management and transformation campaign to make sure the new white theme is on message and brand aligned for Railtrack? You'll have to add at least 1 lawyer, 1 community liaison officer, 2 PR people, an advertising account executive...

> we'll need a mobile toilet booked and installed

Toilet? Pfff. You can't just go out and stick up a toilet....

For all you doubters, this is how it works. And talking of breaks, if a manager says anything to the lads, even non-work related, they're allowed to start their break again.

Does not even matter that majority of the rail in the UK does not operate at night.

For context, a bunch of UK rail staff have been striking lately and one of their demands is no efficiency improvements or compulsory redundances. (They also want a substantial pay increase of course.)

If you read anything about their demands, you will discover that from this year their contract is changing to require more hours at the same pay, so they are literally being given a paycut. In every other industry that would be illegal, but rail workers are expected to just suck it up and be grateful that they even still have a job, right? They protest compulsory redundancies because they know exactly how the British system works - a lot of people will be fired and the rest expected to just pick up the slack and work more hours, without any improvement like automation.

And among other things changes like not being paid for their commute when doing overtime(which was paid for previously), at the time when petrol has crossed £2/L around the country.

Are pay cuts illegal in UK? Wow, that’s insane.

Why is it insane? Maybe I should have clarified - your employer cannot cut your pay without a very good reason and you have to agree to it. In general it's a very tricky process legally, just like letting someone go - you need to make sure it's done correctly or you will lose in court. They cannot just say "from next month you will work extra 2 hours a week at same pay". Like....no? That's not in the employment contract we have signed, it binds both sides. And yet that's exactly what is happening to rail workers.

Your clarification makes more sense -- I also consider reduction in pay to be equivalent to firing, a piecewise one. I understand that it means that has to follow all rules about firing people, and that much I also find reasonable. At the same time, I find the rules about firing commonly found in Europe as wrongheaded, but that's not my complain above, which is about "illegality of pay reduction".

Do we count price increases on healthcare provided through an employer as a paycut? If so, everyone I know has been getting paycuts for years even ignoring inflation.

Why is that insane?

None of the media coverage I've seen or can find seems to mention this supposed paycut due to more hours at the same pay, including in really sympathetic outlets like the Guardian which describes their demands as being exactly what I claimed. In fact, the only change to terms I can find anywhere that even vaguely resembles that is that maybe some staff will no longer get the same generous overtime multiplier on Sunday, and that's from the literal World Socialist site which is vague enough in their wording that I suspect they might be playing sneaky word games again. (They're... not the most trustworthy source.)

It's even spraying in front of the train car and then apparently rolling right over it without much trouble (although I note some white paint on the wheels).

I don't think anyone is expecting the paint to stick to the rolling surface of the rail for very long, but that (on a track with regular usage) gets polished by the passing trains, so it's reflective anyway...

Of course that is not a problem.

What needs to be painted is the sides of the rail, the top - even if painted in the process - will return to lucid metal as soon as the next few trains pass on them.

Usually small trucks (Unimogs adapted to rail use) or small convoys are used, see:

https://scalaenne.wordpress.com/2016/07/30/binari-bianchi/

This is an easy problem to solve. You just have the paint mechanism at the back of the vehicle so it paints after the wheels have moved over the track. Kind of like the reverse of the plough at the front of the train that some networks (not U.K.) have to clear the track before the wheels pass over it.

or just paint behind the robot

And use a pencil instead of inventing a pen that works in zero gravity.

The pencil introduced graphite dust into the air that caused electrical problems.

This is why astronauts use a pen. Sometimes the "cheap and simple" way has side effects that are more harmful than the original problem.

And Russian space station (while they had one) was notorious for repeated fires.

Probably that approach to safety was cause for it.

Oil pencils and wax pencils are a thing too.

They are, and the Soviets stopped using them because

- The paper peeled away is a fire hazard

- The oil and wax writing smudges and is a terrible way of writing

- The floating bits of paper from sharpening the pencils was a mess and since they float, got in people's faces.

Generally those are terrible ideas too, especially compared to a $100 for a pen. It's really not that much compared to every other cost.

What about mechanically advancing wax rods? The question isn’t whether the unit price of a super-pen is less than that of a consumer-waxpencil, but rather the R&D cost of the super-pen vs that of a supposed super-waxpencil.

NASA didn't spend any R&D on it as it was developed by a third party, so that point is moot as the answer is $0.

https://www.scientificamerican.com/article/fact-or-fiction-n...

Painting vehicle and robot likely cost pretty much the same. And with vehicle you don't really need to think about all of the nitty gritty details of autonomous operations or regulations.

How would this be any better then the video? It would also be much more expensive and complex then what they made.

Do it from the back end while it moves forward?

It still blows my mind that the color of something makes such a difference.

Wait until you hear about how much money we could be saving if roofs were white instead of the typical dark gray. (Locale: en-US)

Wait why aren't roofs white then?

They are in many parts of the world. The reasons why they aren’t in other parts of the world are many, but they include the fact that bitumen as a petroleum byproduct has been cheap; other traditional roof materials used in Western Europe are also naturally fairly dark; in cooler climates heating has historically been a more pressing concern than cooling; people migrating from said cooler climates have not bothered to adapt their construction methods to local conditions; AC powered with cheap fossil energy has been seen as a silver bullet; people choose to avoid upfront expenses even if that means suffering in the future; cooling is rapidly becoming a concern even in said cooler climates, but adaptation lags behind because people are surprised that the climate change is actually now their problem and not some future people’s problem…

Just built a house in Ireland (moved here from California) and have been very glad we ignored basically all the advice people wanted to give us and went for things that make it easy to cool. High ceilings with roof windows to vent heat have made the last couple days much more pleasant. Really glad it's wood and we're not dealing with all that thermal mass people here seem so enamored of.

I also have a 200 year old stone cottage and when it gets hot it stays hot for a very long time (same for being cold).

Thermal mass makes sense if exposure to heat can be carefully controlled, in a manner consistent with solar passive principles. Ideally this would be in the form of concrete floor/brick wall behind a glazed and shaded south-facing window (northern hemisphere) in an otherwise well insulated house.

In practice, it’s generally better to just have a well insulated house in the first place. (Passivhaus being the attainable ideal.)

True, and thermal mass is amazing if you have a lot of giant rocks and use them to soak up sun and keep fruit trees warm at night, allowing you to grow fruits normally suited to much warmer climates.

My experience was mostly old brick buildings in Dublin (old enough to not be cavity wall) and having all the heat they soaked up during the day radiated back at you at night.

I plan to add retractable awnings over the windows that get a lot of sun at some point too; they can make a big difference.

And, of course, trees! Deciduous trees give you shade in the summer and kindly drop their leaves so you have light in the winter. They're amazing!

Thermal mass can definitely be useful when you don't have air conditioning. Most of the older building in countries like Peru had thick walls (as well as tall ceilings) and were far cooler than outside during the day since the thermal mass effectively buffered the indoor temperature between night and day.

True, I think I'm just a little grumpy from years of boiling hot apartments in very old buildings.

There is such a thing as white bitumen, and Obama's Nobel-laureate Secretary of Energy Steven Chu had suggested we adopt it.

Because they produce glare for neighbors. Also tradition. Mirrors would be even better, but apart from expense and weight, worse for anyone in the path of the glare :-/ [edit: reply comment to this says mirrors wouldn’t actually be better]

But, for example, California is requiring light roofs and other mitigating issues, so there is some progress.

BTW if you do decide to paint your roof (or any other external surface) please use TiO2 paint as the UV from the sun will then cause it to break down pollutants like NOx and greenhouse gases like methane.

Mirrors have low emissivity. While they accept a bit less heat, they will hold on to it more than something with white paint (which can have pretty good emissivity) and will thus get hotter.

Thanks, that’s interesting. Al is a pretty good IR reflector, and I believe most common mirrors these days use it as the reflective coating. Is the glass the problem?

Given that window glass can get damn hot when exposed to strong sun, and situating a perfect reflector behind it would presumably double the effect, intuition leads me to guess that yes, the glass would be a problem.

Cultural norms are really hard to change. There is no reasonable world in which businesspeople in the US south and southwest should wear suits and ties. But if they didn’t, they would not be taken seriously in our culture.

If you live in the north, it's so you don't have roof collapses in the winter due to snow buildup.

If you live in the south, it's because people think there isn't good roofing materials that can be lighter colors. Those people are wrong.

Once the snow is covering the roof the color can’t matter? This would only have a marginal effect on very mild snow to melt it before it accumulates. Snowy days also don’t have much sun to catch to begin with, clouds ya know. No, roof collapses are prevented by stronger and more sloping roof.

I can tell you're not from the north. Snowy days aren't dark and cloudy. You'll wear sunglasses sometimes. Dark roofs absolutely help melt snow. The snow starts melting near the gutters and then climbs upward. The snow also sublimates. When it gets really cold, clouds can't form so there are a lot of bright days without a cloud in the sky.

The north could (and is!) solved by metal roofs that are white or light colored and steep - steep enough that snow slides right off.

The roof of the apartment building where I live is silvery-white.

It makes totals sense. I also suppose that many people who own single-family houses would not do that, mostly because it looks odd. Looking odd is something that makes people uncomfortable.

When you find a way for a light-colored roof to look cool while also not costing an arm and a leg, people will gladly adopt it. This happened to solar panels when they started to look well and also signal wealth and care of the Earth.

Many newer roofs are white. For example, EPDM roofs are all near-white.

Meh, my EPDM roof is black.. I think you’re thinking of TPO?

a tricolour dog or cat that's been sitting in the sun is how I discovered this as a child!

How did you decide what 3 colors to paint them with for the test?

It sounds like a natural experiment to me - genetics decided the colors (I'm guessing black, white and brown: colors commonly found in multicolored cat & dog breeds)

This is also why I paint my CPUs and GPUs black.

[1] https://duckduckgo.com/?q=la+painting+streets+white

I suppose you could as well polish them very well, but I think that will last shorter time than paint.

It’s easily relatable, compare wearing a black vs white t-shirt a warm sunny day.

And for a better effect they could use paint that can cool below the ambient temperature by radiating infrared to space (if they aren't already using that, but it's probably more expensive):

https://www.nature.com/articles/d41586-019-03911-8

Here is a YouTuber trying to making such paint:

https://www.youtube.com/watch?v=N3bJnKmeNJY

Another article:

https://greekreporter.com/2022/05/08/revolutionary-white-pai...

The same thing is done to roofs in hotter climates; modern roof paint (expensive, it was $160 a gallon when I used it) on a roll roof can drop interior house temperatures 5-10 degrees or more.

We replaced our 40 year old tar and gravel roof (with small light colored stones) with a dark colored architectural shingle. There was an immediate, noticable difference. On summer nights you could feel the heat radiating out of the attic after a long day in sun.

This was in a cold climate, albeit at high latitude, so long days and low sun angle in the summer means more insolation. Since we rarely get above 70F here, I didn't think it would make much difference. Of course, it's only noticable a couple months out of the year.

In a cold climate it could help with heating costs though, I suppose?

It might help if we had some sunny fall days, until the snow flies, anyway.

Does this increase the longevity of the roofing material if used on something like asphalt shingles?

It can, yes. But often with shingles you’re better of replacing them when worn with shingles that have the reflectivity “built in”.

They started doing that a few years ago. Can see it in action on the main bridge going towards Glasgow Central as there's lots of points (15 platforms), seemed to help.

Alternately, I've seen videos in the likes of Chicago where they've literally installed pretty much bunsen burners and set the rails on fire to deal with the winter. https://www.youtube.com/watch?v=z76ywZDXyPw

From the video: first trials achieved a cooling by 5 to 8°C.

Somewhere it was written that the ground underneath the trackbed also sinks in as it dries out. Is this not a mostly universal problem in addition to the temperature the tracks reach because of direct sunlight and lack of cool air?

Don’t the majority of trackbeds deform when the ground below them shrinks like a dry sponge? Exceptions may be a railroad bridge built on bedrock?

Why aren't they painting them backwards though?

Good point. However the paint in the hip is going to rub off anyway and what’s underneath is reflective.

how long does the paint last?

I believe it lasts quite a while on the sides and the top is rubbed to a reflective shine when trains run over it anyways.

Can't eroding paint chips pollute the environment ?

Same as when you fart

So einfach, so wirksam

Unable to find guidelines or comment from the mods, but HN’s comments are in English, please use English unless it is a comment in English explaining a non-English term.

(Dang, please clarify HN’s position on non-English comments; believe I recall seeing this before, but unable to find guidelines or comment from you. Thanks.)

EDIT: Related comment from Dang on use of non-English submissions:

https://news.ycombinator.com/item?id=27571809

I agree completely with "comments in English, please". but despite not learning any German for over 50 years, I came up with "One think works", which is not too far off!

"So easy, so effective" seems like the most appropriate translation in this case

Submissions are community property, so to speak, so the rules are stricter for those.

There's a lot more room for individual expression in comments. If someone's quoting a saying or making a quip that's best expressed in another language, that's fine. If they're consistently posting in a way that most people here can't understand, we'd ask them to stop.

Understand and agree, thanks for taking the time to respond!

Submissions have to be in English. The problem with the GP comment is not that it's not in English, it's that's it's tropey and unsubstantive. Just flag bad comments and move on.

Kannitverstaan! Was Du saggn?

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