What makes people feel safe at night? On the science of street lights

Street lights in Kabul, shortly after they were installed for the first time in 2003. Image: Getty.

Winter is coming: the nights are drawing in and in the Northern Hemisphere the hours of darkness already outnumber the hours of daylight. Research has shown that darkness produces a big fall in the number of people out walking – and a major reason for this is that people feel less safe walking in the dark.

There may be an evolutionary explanation for why people feel less safe at night – we can’t see as well, and this may have exposed our ancestors to greater threat from predators. Nowadays, it’s not so much the prospect of being eaten by a savage beast that concerns would-be pedestrians, but the fear of being mugged or victimised.

Some studies suggest that new outdoor lighting can reduce crime rates in an area, but there is conflicting evidence on this. A large review of research found a link between new lighting and reduced crime rates, but improvements were seen in daylight as well as darkness, suggesting that street lighting is not the only factor. This review has also been criticised by other researchers, and a large statistical analysis found no link between crime rates and switching off or dimming street lighting at night.

Street lights may or may not have an effect on crime, but one thing’s for sure – brighter levels of light do make people feel safer when walking at night. This can lead to a significant increase in the number of minutes people spend walking each week. It can also reduce the number of people who avoid leaving their homes at night, reduce social isolation, improve physical and mental well-being and increase community pride.

Street lighting can improve the quality of neighbourhood life by making people feel safer – but, even so, it would be unwise to flood our streets with light at night. Street lighting costs money: the UK’s annual bill is estimated at around £220m. Artificial light at night may also have a negative impact on wildlife and the natural world, for example by stunting the growth of frogs and toads and preventing them from laying their eggs.

The skyglow from street lights also means we rarely get to see the true wonder of the night sky, frustrating astronomers and limiting our appreciation of the natural environment. For these reasons, lighting should be used selectively and efficiently – and this requires good guidance to help those responsible for installing and maintaining our street lighting.

The guidelines for street lighting in the UK and many other countries are currently based on questionable evidence. That’s why our lighting research group at the University of Sheffield undertook a programme of research to find out how lighting relates to feelings of reassurance after dark, and improve the evidence on which lighting guidelines are based.


Illuminating evidence

In one recent experiment, we asked people to walk along a number of streets in the city of Sheffield at night and rate how safe they felt. We also asked these people to walk and rate the streets in the day, to create a baseline measure of safety and to account for biases that may occur if safety ratings were taken only after dark.

The difference in safety ratings between the day and night walks told us something about the lighting on that street – the smaller the difference between day and dark ratings, the safer people felt due to the lighting. We compared our participants’ different ratings against measures of the lighting on each street, including the average illuminance (amount of light falling on the street surface) and uniformity (how evenly spread out the lighting was).

Today, average illuminance is the main measure used when installing and evaluating street lighting. But we found that, while increasing average illuminance was linked with improved feelings of safety, uniformity was more important for making people feel safe. So it might be more important to have evenly distributed lighting, rather than bright lighting, to make people feel safer.

Local authorities are undergoing major changes to their lighting, as they replace the traditional orange sodium lamps with new LED lighting. These new LEDs are more energy efficient, which saves taxpayers’ money. They also give councils greater control over the lighting they provide, for example by dimming and switching off when there are no pedestrians about.

Used properly, street lights can improve people’s lives and help neighbourhoods come alive at night. But there’s still a lot to discover about how people respond to street lighting and the impacts it has on society and the environment – experiments such as these can help to light the way.

The Conversation

Jim Uttley, Research Fellow, University of Leeds; Aleksandra Liachenko Monteiro, PhD Candidate, University of Sheffield, and Steve Fotios, Professor of Lighting and Visual Perception, University of Sheffield.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

 
 
 
 

What are Europe’s longest train journeys?

The Orient Express was a pretty long train. Image: Getty.

For reasons that aren’t clear even to me, a question popped into my head and refused to leave: what’s longer? Britain’s longest train joruney, or Germany’s?

On the one hand, Germany is quite a bit larger – its area is 70 per cent more than Great Britain’s. On the other hand, Great Britain is long, skinny island and Germany is much rounder – the distance from John O’ Groats to Lands End is over 1,400 km, but you never have walk over 1,000 km to cross Germany in any direction.

And it turns out these factors balance almost each other out. Britain’s longest train, the CrossCountry from Aberdeen in Scotland to Penzance in Cornwall, runs 785 miles or 1,263 km. Germany’s longest train, the IC 2216 from Offenburg in the Black Forest to Greifswald on the Baltic coast, is exactly 1,300 km. Germany wins by a tiny distance.

Except then I was hooked. What about the longest train in France? Spain? Italy?

So I did what anyone would do. I made a map.

The map above was all drawn with the Deutsche Bahn (Germany Railways) travel planning tool, which rather incredibly has nearly every railway in Europe. The data quality is better for some countries than others (the lines in France aren’t quite that straight in real life), and the measurements may be a bit off – it’s not always easy to find the length of a train service, especially when routes can vary over the year – but it gives us a good idea of what the routes look like.

Let’s start with the UK. The Aberdeen to Penzance route isn’t really for people who want to go all the way across the country. Instead, it’s a way to link together several railway lines and connect some medium-to-large cities that otherwise don’t have many direct services. “Cross-country” trains like these have existed for a century, but because they crossed multiple different company’s lines – and later, multiple British Rail regions – they tended to get ignored.

 

That’s why, when it privatised the railways, the government created a specific CrossCountry franchise so there was a company dedicated to these underused routes. If you want to get from Edinburgh to Leeds or Derby to Bristol, you’ll probably want a CrossCountry train.

The usual route is Edinburgh to Plymouth, but once a day they run an extra long one. Just one way though – there’s no Penzance to Aberdeen train. 

The longest train in Germany is weird – at 1,400 km, it’s substantially longer than the country itself. On the map, the reason is obvious – it takes a huge C shaped route. (It also doubles back on itself at one point in order to reach Stuttgart).

This route takes it down the Rhine, the biggest river in west Germany, and through the most densely populated patch of the country around Cologne and Dusseldorf known as the Ruhr. Germany’s second and third longest trains also have quite similar routes – they start and end in remote corners of the country, but all three have the Rhine-Ruhr metropolitan area in the middle.

You’re not meant to take the IC 2216 all the way from north east to south west – there are much more direct options available. Instead, it’s for people who want to travel to these major cities. They could run two separate trains – say, Offenburg-Dusseldorf and Griefswald-Cologne – but making it a single route means passengers benefit from a bit more flexibility and helps DB use its rolling stock more effectively.

France’s longest train exists for a very good reason. Most of France’s high-speed lines radiate out from Paris, and it’s very hard to get around the country without going to the capital. Usually to get from Marseille on the Mediterranean to Nantes near the Atlantic, you’d need to take a TGV to Paris Gare de Lyon station, then get the Métro across the city to Gare Montparnasse.

Once a day though, this TGV avoids this faff by stopping in the suburb of Juvisy and turning around without going into the centre. This lets passengers travel direct between the coasts and reduces the traffic through Paris’s terminals in the rush hour. The exact length of this route isn’t clear, but Wikipedia says it’s about 1,130 km.

Spain’s longest train is very different. This is the Trenhotel sleeper service from Barcelona to Vigo, and it’s pretty fancy. This is a train for tourists and business travellers, with some quite luxurious sleeping cabins. But it is a regularly scheduled train run by the state operator Renfe, not a luxury charter, and it does appear in the timetables.

Being dry, hot and quite mountainous in its middle, most of Spain’s cities are on its coast (Madrid is the one major exception) and as a result the train passes through relatively few urban areas. (Zaragoza, Spain’s 5th largest city, is on the route, but after that the next biggest city is Burgos, its 35th largest,) This is partly why overnight trains work so well on the route – without many stops in the middle, most passengers can just sleep right through the journey, although there are occasional day time trains on that route too if you want to savour the view on that 1,314 km journey.

Finally, there’s Italy. This is another sleeper train, from Milan in the north to Syracuse on the island of Sicily. It goes via Rome and travels along the west coast of... wait, it’s a train to the island of Sicily? How, when there’s no bridge?

Well, this train takes a boat. I don’t really have anything else to add here. It’s just a train that they literally drive onto a ferry, sail across the water, and then drive off again at the other side. That’s pretty cool.

(As I was writing this, someone on Twitter got in touch to tell me the route will get even longer in September when the line to Palermo reopens. That should be exciting.)

So those are the longest trains in each country. But they aren’t the longest in Europe.

For one thing, there are some countries we haven’t looked at yet with very long trains. Sweden has some spectacular routes from its southern tip up into the Arctic north, and although the Donbass War appears to have cut Ukraine’s Uzhorod to Luhansk service short, even Uzhorod to Kharkiv is over 1,400 km. And then there are the international routes.

To encourage the Russian rich to take the train for their holiday, Russian Railways now run a luxury sleeper from Moscow to Nice, passing through France, Monaco, Italy, Austria, Czechia, Poland, Belarus and Russia. This monster line is 3,315 km long and stretches across most of the continent. That’s got to be the longest in Europe, right?

Nope. Incredibly, the longest train in Europe doesn’t actually cross a single border. Unsurprisingly, it’s in Russia, but it’s not the Trans-Siberian – the vast majority of that’s route is in Asia, not Europe. No, if you really want a long European train journey, head to Adler, just south of the Olympic host city Sochi. From there, you can catch a train up to Vorkuta on the edge of the Arctic Circle. The route zigzags a bit over its 89 hour, 4,200 km journey, but it always stays on the European side of the Ural mountains.

Bring a good book.

Stephen Jorgenson-Murray often tweets about this kind of nonsense at @stejormur.


All maps courtesy of Deutsche Bahn.