Tag Archives: fire

Full evacuation


It is a well-known fact that when alcohol kicks in, common sense flies out the window. And with the loss of common sense, the ability to perceive danger, follow instructions, cooperate and move around is also impaired, all of which impacts on an evacuation. Two students from the Technical University of Denmark (DTU) have proven this.

As is widely known, when you consume alcohol, your balance, motor coordination and judgement are impaired. You move differently and you are slower to grasp things – if you grasp them at all. However, none of that is taken account of when simulating an evacuation and organising fire safety and the evacuation of a night club. On the other hand, you can be assured that people will be intoxicated. Instead, the same standards are used for how quickly people move and react as they do in all other buildings.

But, doesn’t alcohol affect how people react in the event of an evacuation? This topic was investigated by two students from DTU, Anne Madsen and Marlene Westmose, for their dissertation.

– We set up a trial in which the participants drank alcohol and conducted various tests in order to test their motor coordination, reaction time and walking pace. First of all, we conducted a reference test during which they were unaffected by alcohol and then we repeated the tests in which the participants were affected by various amounts of alcohol, explains Marlene Westmose.

The tests included, for example, a test of their walking pace and a so-called ‘flamingo test’ whereby the number of times the participants lose their balance when they stand on one leg for a minute is recorded.

Poor perception of own safety
Already after two beers the participants’ balance clearly affected. And, after six beers, which was the maximum permitted in the trial, both the test results and the actual tests were significantly different.

– One of the tests was an ‘up-and-go-test’ whereby the participants had to get up from a chair and run around another chair placed 2.5 metres away and then sit back down on the first chair. After drinking, the participants were overly confident and began to fall over the chair. They had a far poorer perceptions of their own safety, says Anne Madsen.

At the same time, they behaved differently. In the walking pace test, which they did in a group, the participants helped one another far less and it was more about completing the test as quickly as they could for their own sake.

Ruin the mood
Quite simply, the participants’ behaviour changed during the course of the trial. And it was not only in terms of thinking of themselves more and paying less attention to their fellow human beings.

– Existing research shows that, in the event of a fire, recorded warnings work best and shorten the response time in an evacuation of adults who are not under the influence of alcohol. However, in the trial, it was clear that the intoxicated participants generally didn’t listen to what was being said. Therefore, you must question whether this is the best way of getting drunk people to evacuate, says Anne Dederichs, who was dissertation adviser to the two students.

She is a lecturer in DTU’s Department of Civil Engineering where she, among other things, researches the evacuation of people with impaired abilities, including those under the influence of alcohol, and it was she who recommended that the two students research the subject, and who had received support from Knud Højgårds Foundation, the Tryg Foundation and Carlsberg to carry out the trials.

– Perhaps, in order to get through to people, it would be better if we looked at how the mood is ruined. For example, by turning the music off or using a loud siren wail instead, says Anne Dederichs.

More research
Even though the trial gives you an idea of how intoxicated people behave during an evacuation, the results in themselves are no substitute for data in the simulation of an evacuation.

– Based on the results, we must expect that the reaction time and the time it takes to make a decision are longer for intoxicated people. In any case, we can see some trends. But, on the basis of our trial, we can’t conclude anything general about how people behave when they are under the influence of alcohol, says Marlene Westmose.

– The trial provides some data, which we have processed, and which will hopefully result in a scientific article. But, first and foremost, the trial will intensify the focus on the problem and show that more research is needed, adds Anne Madsen.

Meanwhile, the two students can be pleased with their finished dissertations, for which they both received top marks.


The ethics behind getting participants drunk

It is difficult to work with alcohol in a scientific trial. Carlsberg supported the trial so there was no shortage of beer. However, on the one hand, fires in nightclubs have cost many human lives so there is a need for knowledge about how people behave when they are under the influence of alcohol. But, on the other hand, how do you ensure, at the same time, that no one suffers any harm or feels uncomfortable when part of the trial involves alcohol?

– Besides the Danish ethical rules governing the area, we used a code of ethics developed by the Evacuation Group at DTU’s Department of Civil Engineering. This meant, for example, that all participants were informed that they could withdraw from the trial at any time and that there was no requirement for them to drink six beers, which was the maximum limit in the trial, explains Marlene Westmose.

– It is a sensitive area, but it was handled in accordance with all the relevant rules, and the plan for the trial was submitted to both the Danish Council on Ethics and the Danish Data Protection Agency, says Anne Dederichs.


Fires in nightclubs

There are good reasons for investigating how you can ensure the smooth evacuation of nightclubs. This is because, throughout history, there has been several examples of fires in nightclubs where frighteningly large numbers of people have not made it out. The most recent example was in Romania where 31 people died in October 2015 when the fireworks in a stage show set fire to the ceiling in a nightclub.
Over the years there has been several incidents where nightclubs have formed the backdrop for tragedies. The five most deadly are:

  • 494 fatalities – Coconut Grove Night Club, Boston, USA, 1942.
  • 309 fatalities – Dance Hall, Luoyang, China, 2000.
  • 242 fatalities – KISS Nightclub, Santa Maria, Brazil, 2013.
  • 207 fatalities – Rythm Club Dance Hall, Natchez, USA, 1940.
  • 194 fatalities – Cromagnon Republic Club, Buenos Aires, Argentina, 2004.

Flashing signs lead to quicker evacuation


When evacuation signs start flashing, evacuation takes place more quickly and is more evenly distributed. This has been demonstrated by studies from abroad. And new technology also reduces the big unknown in every evacuation: the response time.

Example: A fire breaks out in an airport terminal. The detection system senses the fire at once and the evacuation signs automatically start to flash. The public address system asks all travellers to leave the terminal via the evacuation routes. However, not all the evacuation signs flash green. Instead, some have a flashing red cross at the top. This is because the fire detection system has registered that the fire has broken out near two of the evacuation routes. And so, to divert the public away from the risk zone, the signs above these evacuation routes flash with a red cross.

Another example: A shopping centre is attacked by armed terrorists. Using fire detection systems, dynamic signage, public address warnings, evacuation simulation programs and video cameras, the shopping centre’s safety officers are able to guide customers and other civilians away from the terrorists and out of the centre, without running into the terrorists’ guns.

Flashing signs tell you to choose a different route
These are imaginary examples, but could easily become reality if the various fire fighting systems were linked together. This is something currently being researched in other countries, for instance in EU-financed projects. These have investigated the effect on evacuation of dynamic evacuation signs – in other words, where the signs flash when the alarm goes off, with a red cross over them if the public needs to choose a different route.

– Experiments show that the public will evacuate more quickly than usual with the dynamic signs, says Lise Olesen, a fire safety consultant at the Danish Institute of Fire and Security Technology (DBI). She continues:

– This isn’t a technology we have seen much of in Denmark. But it could easily be of benefit for evacuating airports or conference halls, where many people are gathered together and are unfamiliar with the escape routes. The same goes for night clubs, where it can be difficult to find your way out and where it is hard to attract people’s attention.

Both the above examples would be possible if the technology was fully implemented and all systems were able to communicate. But complete linkage of all systems is unnecessary for achieving quicker and better evacuation. If just the fire safety systems and the lighting on the evacuation routes lighting can communicate, so that signs will flash when the alarm goes off, this can have a positive effect.

Bringing down response time
Many people don’t notice evacuation signs. Even if we are familiar with the green signs with the stylised icon of a man running towards a door, few people notice them in daily life. We become blind to them – even, unfortunately, when disaster strikes.

– The majority of people will try to escape the same way they came in, without much noticing what the signs say. But if the signs are actually flashing, they attract our attention, and this can lead both to quicker evacuation and less congestion at the main entrance, where most people will typically try to exit, Olesen says.

The flashing sign can also help to bring down the response time – which means the time from when the alarm goes off to when the public start to evacuate the building. Sometimes this can take a considerable period of time.

– When the alarm goes off, there are a number of factors which affect how long people take before they react. Humans are herd animals, so first of all we look to see how other people are reacting. And if you’ve just been served with a steak, you’ll prefer to sit and finish it. After that, you’ll need to find your jacket, your children, your friends or go to the toilet. That is why the response time is the big unknown in an evacuation situation, and dynamic signage can bring down that time, Olesen maintains.

The technology is out there
In rapidly developing fires, every minute counts, so the effect of linking systems and using dynamic signage can be significant.

– Every reduction in response time can potentially save life, and technology provides a number of opportunities for improving safety. This is true of both advanced and simpler solutions, Olesen explains.

It is still uncertain when or how the technology will become widespread but the possibilities are already with us.

– It’s not a question of technology, because we already have what we need to realise the simple solutions. It’s more a question of getting the different systems to cooperate, Olesen says.