What is the “Correct” Speed Limit?

From “Not Just Bikes”. ( YouTube / Nebula )

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There’s a trend towards lower speed limits in cities all over the world, but why is this happening? What is the research behind it? And what is the "correct" speed limit for cities, anyway?

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References & Further Reading

Confessions of a Recovering Engineer
Charles "Chuck" Marohn

SWOV Fact sheet – The relation between speed and crashes

Rosén, E., Stigson, H. & Sander, U. (2011). Literature review of pedestrian fatality risk as a function of
car impact speed. In: Accident Analysis and Prevention, vol. 43, nr. 1, p. 25-33.

NACTO – Impact Speed and a Pedestrian’s Risk of Severe Injury or Death

Nilsson, G. (1982). The effects of speed limits on traffic accidents in Sweden. In: Proceedings of the international symposium on the effects of speed limits on traffic accidents and transport energy use, 6-8 October 1981, Dublin. OECD, Paris, p. 1-8.

Kinetic energy management in road traffic injury prevention: a call for action

Stopping Distance Calculator

New crash tests show modest speed increases can have deadly consequences – IIHS News

Speed and the Laws of Physics
Société de l’assurance automobile du Québec

Shaffer, D.M., Maynor, A.B. & Roy, W.L. The visual perception of lines on the road. Perception & Psychophysics 70, 1571–1580 (2008). https://doi.org/10.3758/PP.70.8.1571

Driver Reaction Time
Marc Green – Human Factors & Science

The Effect of Driving Speed on Driver’s Visual Attention: Experimental Investigation

The Critical Ten – Stgreets.mn

The Critical Ten

Zhang, W., & Peterson, M. (2011). Predicting Patterns of Potential Driver Distraction Through Analysis of Eye-Tracking Data.

Why Speeding – Just a Bit – Can Be Dangerous
ARCON Forensic Engineers

Serious Injuries 2018 – European Road Safety Observatory

Svenson, Ola (February 1981). "Are We All Less Risky and More Skillful Than Our Fellow Drivers?" (PDF). Acta Psychologica. 47 (2): 143–148. doi:10.1016/0001-6918(81)90005-6.

McCormick, I. A.; Walkey, F. H.; Green, D. E. (June 1986). "Comparative Perceptions of Driver Ability: A Confirmation and Expansion". Accident Analysis & Prevention. 18 (3): 205–208. doi:10.1016/0001-4575(86)90004-7. PMID 3730094.

E. Verheijen and J. Jabben, Effect of electric cars on traffic noise and safety,
RIVM report 680300009/2010, http://www.rivm.nl/bibliotheek/rapporten/680300009.pdf

Alexander RG, Macknik SL, Martinez-Conde S. Microsaccades in Applied Environments: Real-World Applications of Fixational Eye Movement Measurements. J Eye Mov Res. 2020 May 15;12(6):10.16910/jemr.12.6.15. doi: 10.16910/jemr.12.6.15. PMID: 33828760; PMCID: PMC7962687.

Slowing city traffic cut road deaths by a quarter

Too Fast, Too Furious: New York City’s Speeding Epidemic


0:00 Intro
0:45 False Start NJB Logo
0:51 Real NJB Logo
0:56 Why 30km/h?
1:33 Noise
2:27 Kinetic Energy
3:33 Mass
4:24 Microcars
5:08 Walking & Cycling
6:15 Avoiding Crashes
7:36 Visual Perception
9:29 Overconfidence
9:52 "That guy"
10:17 Mobility vs Safety
11:04 Faster and Slower
12:22 Too Much Traffic?
13:04 Brainerd Traffic Lights
14:47 Removing Traffic Lights
15:53 Painfully Inefficient Stroads
16:29 Building Great Streets
17:27 Fuel Efficiency
18:30 The Benefits
19:44 Conclusion & Assholes
20:17 Ground News