Why white light is best for our town centres

June 22, 2004

White lighting is twice as good at letting you see the face of someone else as that from the yellow light from high pressure sodium lamps commonly used to light our streets, according to new research sponsored by the ESRC and published as part of Social Science week.

It can therefore allow the same facial recognition as conventional sodium lighting while cutting energy use by 40 - 45 per cent, says a study led by Professor Tadj Oreszczyn, of the Bartlett School of Graduate Studies, University College London.

Professor Oreszczyn said: "People have been putting in sodium light because they think it saves energy. But the truth is, you need more sodium light to be able to see other people's faces properly in pedestrian areas. And if you put in this extra light, you use more energy not less".

Researchers investigated the impact that improved lighting can have on people's sense of security and social and economic activity in Britain's town centres and shopping areas. But Professor Oreszczyn believes the implications of the research apply to all lighting for pedestrians.

The laboratory study of white light and facial recognition was used to compliment the research in which new lighting was installed in Sutton Coldfield town centre and the local urban area of Swinton. Interviews took place with more than 3,500 visitors to these sites before and after the relighting.

And virtual reality techniques were used for the first time in the lighting design process at focus groups with retailers, town centre managers, and young people known to the police. Issues raised at these sessions led to the laboratory investigation into the importance of the colour of light in people's ability to recognise faces - an important contributing factor in people's sense of personal security in town centres at night.

Professor Oreszczyn said: "Previous recommendations on street lighting for pedestrians required set lighting levels irrespective of the colour."

"This has resulted in the widespread use of high pressure sodium lamps, due to their greater energy efficiency and long life. But the information we have gathered suggests that this is a false economy."

"We found that you need about half as much white light as yellow to be able to recognise faces at a given distance, with an energy saving of somewhere around 40 to 45 per cent."

One of the major factors facing people using urban spaces is the fear of crime, and this is linked to their ability to recognise faces before somebody enters their 'personal space.' The study found that people aged over 45 need 30 per cent more light than those under that age in order to recognise faces to the same degree.

Professor Oreszczyn said: "This may in part explain why the fear of crime at night time is greater among the elderly. Our study has shown that normal standards of lighting, if applied using high pressure sodium lamps, will not provide the necessary level of lighting to alleviate fear."

These significant new findings are being passed on to lighting designers and researchers through industry journals, and incorporated in British Standard design guidance for road lighting. The result will be a significant change to UK urban lighting.
-end-
For further information, contact: Professor Oreszczyn on 020-7679-5906 or 07810-153730 e-mail: t.oreszczyn@ucl.ac.uk. Or Iain Stewart, Lesley Lilley or Becky Gammon at ESRC, on 01793-413032-413119-413122.

Economic & Social Research Council

Related Facial Recognition Articles from Brightsurf:

The brain's facial recognition area doesn't differentiate outgroup members
A quirk in how the brain processes faces makes it harder to tell members of a racial outgroup apart, according to new research published in eNeuro.

The facial expressions of mice
The face of a mouse reveals its emotions.

Facial expressions don't tell the whole story of emotion
Facial expressions might not be reliable indicators of emotion, research indicates.

Facial recognition software has a gender problem
A new study of popular facial analysis services found they misidentified trans men as much as 38% of the time, mischaracterized non-binary individuals 100% of the time and appeared to be based on outdated gender stereotypes.

Facial recognition technique could improve hail forecasts
The same artificial intelligence technique typically used in facial recognition systems could help improve prediction of hailstorms and their severity, according to a new study from the National Center for Atmospheric Research (NCAR).

Using facial recognition technology to continuously monitor patient safety in the ICU
A team of Japanese scientists has used facial recognition technology to develop an automated system that can predict when patients in the intensive care unit (ICU) are at high risk of unsafe behaviour such as accidentally removing their breathing tube, with moderate (75%) accuracy.

Half a face enough for recognition technology
Facial recognition technology works even when only half a face is visible, researchers from the University of Bradford have found.

Bacteria use their enemy -- phage -- for 'self-recognition'
Scientists discovered that cells can distinguish themselves from closely related competitors through the use of a virus, and the harboring of phage in bacterial genomes benefits host cells when facing competitors in the environment.

Facial recognition software to identify Civil War soldiers
Photo Sleuth may help uncover the mysteries of nearly 4 million photographs of Civil War-era images.

New legislation needed to regulate police facial recognition technology
Facial recognition technology, being trialled by two major police forces in Britain, should be subjected to more rigorous testing and transparency, according to new research from the University of East Anglia (UEA) and Monash University.

Read More: Facial Recognition News and Facial Recognition Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.