Daytime Running and Xenon High Intensity Discharge light studies: A scientific battleground






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21 December 2010
























































Expert Ophthalmological Studies on blinding by DRL and Xenon-HID lamps


These expert ophthalmological and neurological documents listed opposite explain in graphic medical terms why DRL and HID lamps are dangerous. Whilst the flawed DRL studies below claim accident reductions typically 11%,
in reality NO European country can produce evidence that DRL save lives.
Tragically DaDRL are collecting evidence that DRL KILL - see charts in What's New In mandating DRL the European Commission and their traffic focussed advisers have neglected to consider the ophthalmological and neurological effects of blinding other drivers with High Intensity Discharge (HID) Xenon headlamps and High Power laser like LED DRL both of which emit light close to the eye damaging 370nm UV end of the light spectrum. To justify their studies EU traffic "experts" used slides in a laboratory which cannot emulate the photon emissions beamed directly into a driver's eye.
The EU then commissioned meta-analysis (studies of studies) which compounded their errors to produced the desired result.
Only the Japanese Government have carried out real world tests and they determined that 200cd was an appropriate intensity. The EU have mandated 400 - 1,200cd from February 2011 in a futile attempt to compete with the power of the sun!    

In analogy to the Hippocratic oath some particularly conscious scientists are swearing a voluntary oath:

"I promise to work for a better world, where science and technology are used in socially responsible ways. I will not use my education for any purpose intended to harm human beings or the environment. Throughout my career I will consider the ethical implications of my work before I take action. While the demands placed upon me may be great, I sign this declaration because I recognize that individual responsibility is the first step on the path to peace." Heather Stewart

"First, in all my scientific work I will be honest and I will not do anything which in my view is to the obvious detriment of the human race. Second, if later I find that my work is being used in my view to the detriment of the human race I will endeavour to nullify these developments." Peter Reineker

DRL and Xenon-HID light imply a Violation of Protection, offends against the Equality Principle and violates Article Three* of the Universal Declaration of Human Rights

* Everyone has the right to life, liberty and personal security *

How Much Light do we need?  P.Heilig Nov 2010 - deutsch

Prof Heilig lucidly explains how vehicle lights affects the safety of children, adults, the elderly and athletes

Safe Cycling P. Heilig Apr 2010 - english     Safe Cycling P. Heilig Apr 2010 - deutsch

Safe Cycling is a good introduction to the problems blinding Xenon-HID and DRL lights cause vulnerable road users.

Impaired Perception - Driving and Sports P. Heilig Aug 2010 - english
Impaired Perception - Driving and Sports P. Heilig Aug 2010 - deutch

Impaired Perception takes a step further explaining how blinding Xenon-HID and DRL lights cause change blindness, inattentional blindness, effect on Visual Short Term Memory and Capacitive Dysfunction

Why HID Xenon headlights bother older drivers   British Journal of Ophthalmology 2003
M A Mainster, G T Timberlake, Department of Ophthalmology, University of Kansas Medical Center,
"Governmental regulations determine which headlights we encounter. Acceptance or rejection of the current generation of HID xenon headlights ultimately depends on their record in traffic and litigation.


Can Xenon lights affect vision?
Dr. Edgar Leuenberger, Asian Eye Institute  March 2009

Retinal Light Damage 2009 Dr. P. Heilig, Dr. Elena Rozanova, Dr. Jasminka Godnic-Cvar


The CHILD and Daytime Running Lights Dr. P.Heilig Oct 2008

Light Pollution P. Heilig Sep 2010 - english

EPIGUS - Prof. Dr. Ernst Pfleger Sep 2007  Report on the failed Austrian DRL experiment

Monitor on Psychology - inattentional blindness - Siri Carpenter

The Morbid Philosophy of Advertising Dr. P. Heilig Oct 2010
Unrestrained Advertising Dr. P.Heilig Oct 2010 - deutsch

These publications describe how the cumulative effect of roadside adverts diminish safety

Disability and Discomfort Glare of Headlamps - english  Locher, J.&  Kley, F. (2009).
ISAL 8th International Symposium on Automotive Lighting (38 - 42) Munchen
This paper seeks to justify Xenon headlights - it concludes in static laboratory conditions that there is minimal difference between Xenon-HID, LED and normal Tungsten-Halogen headlights if correctly aligned.  However if mis-aligned discomfort glare is present.
A major failing of this static laboratory experiment is not carrying out real-world tests on moving vehicles with Xenon-HID headlamps - when they traverse legal speed humps or potholes they temporarily blind drivers.
This is a real concern as the laboratory was Hella's who make headlights for many vehicles.


Glare from oncoming traffic: Headlight properties -Visual performance and glare – deutsch
Locher, J., Schmidt, S., Isenbort, A., Kley, F.&  Stahl, F. (2008)
Blendung durch Gegenverkehr: Der Einfluss unterschiedlicher Scheinwerfereigenschaften af die Sehleistung und das subjektiv empfundene Blendgefühl. Zeitschrift für Verkehrssicherheit, 54 (1), 10 – 15.


Countermeasures for the effects of reducing Headlight Glare
AAA Foundation 2001  Mace, Garvey, Porter, Schwab, Adrian



Pro DRL Study

Anti DRL Report, Analysis, Response or Critique

NHTSA September 2008 The Effectiveness of Daytime Running Lights for Passenger Vehicles.
States "No significant statistically associations" from DRL
#1. Go to  #2.  Under "Search Document" enter the following document number:  NHTSA-2008-0153-0004     and then click on Go>>      116 page report

Extracts by DADRL indicating that the benefit of Daytime Lights in the USA is inconclusive

SWOV Daytime Running Lights Factsheet  August 2008 - Claims a theoretical 15% reduction in fatal crashes and 10% reduction in injury crashes.   However real word data show accidents have increased and DRL are killing vulnerable road users - see DaDRL critique >>

DaDRL UK critique of SWOV Daytime Running Light Factsheet   June 2008

European Commission August 2006

Saving Lives with Daytime Running Lights (DRL) Consultation Paper

November  2006

FEPA Federation of European Pedestrians Associations - dangers to Pedestrians

Cyclists Touring Club - Response to EC Consultation Paper  - dangers to Cyclists

ECF European Cyclists Federation and ETRA European Twowheel Retailers Association - dangers to Cyclists and Motorcyclists

Motorcycle Action Group UK - Response to the Consultation Paper Saving Lives with Daytime Running Lights

FEMA Federation of European Motorcyclists Associations - dangers to Motorcyclists

National Motorists Association USA - Response to Consultation Paper - dangers to Motorists

DaDRL USA Drivers against Daytime Running Lights USA - Flawed study methodology

DaDRL UK Why the European Commission's proposal of mandatory motorcar daytime running lights is wrong (short )

DaDRL UK Why the European Commission's proposal of mandatory motorcar daytime running lights is wrong (full)

Medical Evidence against Daytime Running Lights - reduced hazard perception - "change blindness

UK Government Department for Transport - summary of submission to EC against DRL

Tessmer 2004 NHTSA An Assessment of the Crash-Reducing Effectiveness of Passenger Vehicle Daytime Running Lamps (DRLs) for National Highway Transport Safety Authority USA (NHTSA). This was an in-house study NHTSA daytime running lights

Comments on Tessmer DRL Study by Association of Drivers Against Daytime Running Lights USA - web link

Prower BMF 2004 (a)  How Tessmer 2004  uses a method of that is inherently biased in favour of motorcar daytime running lights yet still only succeeds in making mixed findings that they reduce accidents  (200kb pdf)




The Association Drivers Against Daytime Running Lights agrees with these papers and supports the Japanese government in their quest to use low non glaring 200cd DRL.

Japanese Government position on DRL

Japan's comment on TRANS/WP.29/GRE/2001/6/Rev.3 (176kb pdf p15) 

Daytime Running Lamp in Japan 1 page comment (11kb pdf)

Japanese Government: Study on the Effects of Four-wheeled Vehicles' Daytime Running Lights on the Improvement of Their Conspicuity and on the Impairment of Conspicuity of Motorcycles

TRANS WP29 GRE 51 10e (245kb pdf)

Japanese Government: Study on the Effects of the Daytime Running Lights of Four-wheeled Vehicles on their Discernibility (and on the Impairment of Conspicuity of Motorcycles)

TRANS WP29 GRE 53 08e Report No. 2 (163kb pdf)


EU IR3 Brouwer Janssen TNO + Theeuwes  Vrije Universiteit 2004 (1,135kb 31 pages)

Do other road users suffer from the presence of cars that have their daytime running lights on?

Milnes DaDRL UK 2005 (a) Critique of the Methodology of IR3

How laboratory tests cannot replicate real life situations  (27kb pdf 2 pages)

EU IR1  State of the art with respect to DRL installations Commandeur 2004 (947kb 69 pages)

EU IR4 DRL Implementation Scenarios Commandeur+Mathijssen 2004 (302kb 19 pages)

EU DRL Final Report Deliverable 3 TNO 2004 (240kb 10 pages)

Milnes DaDRL UK 2005 (b) Critique of “Daytime Running Lights Final Report by TNO 2004”

A summary of the flawed and inconsistent methodology used by the EU Commission and its experts to impose dangerous daytime running lights on an unwitting population. (57kb pdf 7 pages)

Perlot FEMA 2005 Comments on the Final Report on Daytime Running Lights  (37kb pdf 2 pages)

Wells et al 2004  Susan Wells, Bernadette Mullin, Robyn Norton, John Langley, Jennie Connor, Roy Lay-Yee, Rod Jackson 'Motorcycle rider conspicuity and crash related injury: case-control study' BMJ, doi:10.1136/bmj.37984.574757.EE (23 January 2004)    
Cairney & Styles 2003 Peter Cairney and Tanya Styles 'Review of the literature on daytime running lights (DRL)' Department of Transport and Regional Services, Australian Transport Safety Bureau, ARRB Transport Research CR 218 October 2003

EU IR2 Elvik Christenson Olsen 2003 (2,175kb pdf 124 pages)

Daytime running lights  A systematic review of effects on road safety

Hardy MAG 2004 Critique of the Methodology of IR2: Daytime Running Lights - How data is misused and duplicated  (199kb pdf)

Prower BMF 2004 (b)  Why the method of Elvik et al 2003 is unscientific; its findings unreliable; and its cost-benefit calculation baseless  (149kb pdf)

General comment on DRL

Perlot & Prower 2003 “Review of the evidence for motorcycle and motorcar daytime lights” (437kb pdf)

Lassarre 2001 Sylvain Lassarre

'Évaluation de l'expérimentation des feux de croisement de jour dans les Landes'  Rapport de recherche INRETS Septembre 2001 (from Lavoisier press €15.24)

Prower BMF and Thiollier FFMC 2005 Lassarre 2001 A critical review.

How Lassarre 2001 fails to demonstrate a plausible dose-response relationship between the usage rate of motorcar daytime running lights, and the incidence of fatal accidents, as a result of a campaign in les Landes (161kb pdf)


Tessmer 2000 NHTSA A preliminary assessment of the crash reducing effectiveness of passenger car daytime running lamps (DRLs) (71kb pdf 34 pages)

for National Highway Transport Safety Authority USA (NHTSA)

Johnson DADRL USA (b) response to Tessmer 2000  (web link)

Prower BMF 2001 (b) How NHTSA 2000 fails to overcome the problems of method of the daytime running light studies  (98kb pdf)


Hendtlass 2000 Inquiry into Motorcycle safety in Victoria Australia - The Case Against Daytime Running Lights

This report by Dr. Jane Hendtlass was commissioned by the State of Victoria Melbourne Australia, found daytime lights for motorcycles dangerous and advised the Australian Government against adopting them.

General Motors 1999

General Motors Daytime Lights Field Effectiveness Study

Johnson DaDRL USA (a) response to General Motors 1999

This was an in house study by GM who have a self interest in claiming benefits or they could loose millions of dollars for choosing the wrong DRL system. (web link)

HILDI 1997 Note:

This confidential document was unofficially shown to a DADRL member.

For a copy apply to HILDI under the freedom of information act.

(Now merged with USA’s Insurance Institute for Highway Safety IIHS)

Conveniently, the 2005 HILDI/IIHS website ignores the existence of this report and recommends DRL as a benefit.

HILDI 1997 Highway Insurance Loss Data Institute

This report was produced after the introduction of DRL in the USA during 1995 and 1996 by General Motors, VW Saab and Volvo. This anti DRL study is more authoritative than any other report on this page.

Document summary:

Data was collected from 13 major USA insurers pre DRL and post DRL. HILDI analysed 780,611 pre-DRL and 659,816 post DRL insurance policies and found a 3.7% increase in motor car and SUV injuries after DRL were introduced, excluding extra injuries to pedestrians, cyclists and motorcyclists.

Koornstra et al SWOV (EU) 1997 R97-36 (901kb pdf 179 pages)

The safety effects of daytime running lights

Prower BMF 2001 (a) How Koornstra et al 1997 only achieved consistent findings in favour of daytime running lights from their re-analysis of the Swedish and Norwegian data by the adoption of an inconsistent methodology. (45kb pdf)

Bijleveld 1997

Prower BMF 2000 Bijleveld 1997: Calculation of odds ratio values for Austria 1976–1995 Note on Graphs

General comment on DRL

Prower BMF 1996 Answers to six points that are frequently put forward in favour of motorcycle daytime lights

Elvik 1996 A meta-analysis of studies concerning the safety effects of daytime running lights on cars (from Elsevier Press $30.00)

Prower BMF 2000 30 Years on – Do Motorcar Daytime Headlights reduce accidents? (63kb pdf)

Williams AF, Farmer CM 1996. 'Comment on Theeuwes and Riemersma's revisit of daytime running lights'  Accid Anal Prev. 1996 Jul;28(4):541-42 (not available on the internet)

Theeuwes, J. & Riemersma, J.B.J 1996 'Comment on Williams and Farmer's claims regarding Day Time Running Lights' Accident Analysis & Prevention, 28, 799-800 (171kb pdf 2 pages)

Andersson & Nilsson 1981 'The effect on accidents of compulsory use of running lights during daylight in Sweden', Statens Väg- och Trafik-Institutet (VTI), Linköping, Sweden, Rapport Nr208A, 198 (not available on the internet)

Theeuwes J & Riemersma JBJ, 1995 'Daytime running lights as a vehicle collision countermeasure: The Swedish evidence reconsidered. Accident Analysis and Prevention 27(5) 633.642 (1,081kb pdf 10 pages)

NTR 1976  The Nordic Road Safety Council (Nordisk Trafiksikkerheds Råd NTR) recommended that Denmark, Norway and Sweden mandate daytime running lights for motorcars.

Lund 1979 conducted a monitoring study of the effect of the Danish motorcycle law. But embarrassingly, Lund found as a result of the law a slight increase, not the expected decrease, of motorcycle accidents.