Traffic and Safety Informational Series


The goal of this project was to make available clear, concise, and consistent answers to 25 common traffic and safety questions. The information may be altered, distributed, and used as seen fit by area officials and/or transportation professionals.


Any references to the MUTCD are to the 1988 edition.

The opinions, findings, and conclusions expressed in this publication are not necessarily those of the Center for Transportation Research and Education or the Iowa Department of Transportation.

Document Format

All documents are in Microsoft Word format.

If you have any questions or comments, please call CTRE at 515-294-8103.

Traffic and Safety FAQ Sheets

To download/save an FAQ document, right click on the link and select "save target as."

Download FAQ Sheets in Batches

Individual Questions Two-Page Answers One-Page Summaries
1. Won't a "Children at Play" sign help protect our children? answer summary
2. How many bullet holes does it take to kill a sign? (sign vandalism) answer summary
3. Won't a lower speed limit lower travel speeds and the number of accidents? answer summary
4. Why can't I have several driveways to my property where I want them? answer summary
5. Why aren't there better and longer lasting stripes on the road? answer summary
6. Why can't I place a business-related directional sign within the roadway right-of-way? answer summary
7. What factors are considered when locating, controlling, and/or marking pedestrian crossings? answer summary
8. Why isn't there a "School Bus Stop Ahead" sign everywhere a bus stops? answer summary
9. Why can't speed bumps be used on all streets to slow traffic? answer summary
10. Why do you choose the posted speed limit and where do you put the signs? answer summary
11. Can all traffic signals be timed so I receive a green light at every intersection? answer summary
12. How are signals timed to accommodate pedestrians? answer summary
13. Why can't we have stop signs to reduce speeding along my street? answer summary
14. Why can't we have a four-way stop to reduce accidents? answer summary
15. What is the harm in installing an unwarranted traffic control device? answer summary
16. Won't a traffic signal reduce accidents? answer summary
17. Safe driving procedures at railroad crossings answer summary
18. How do you decide where to place signs? answer summary
19. How does the county make decisions about dust control on gravel roadways? answer summary
20. When do intersections receive stop signs (two-way and four-way) and signals? answer summary
21. Why converting a four-lane street to a three-lane street may improve safety and not increase congestion? answer summary
22. Why do light poles have to be located so far from the street? answer summary
23. How does the county make decisions about paving gravel roadways? answer summary
24. Why don't we have crossing guards at all school crossings? answer summary
25. Won't a flashing yellow light draw more attention to a sign? answer summary

CTRE is an Iowa State University center, administered by the Institute for Transportation.

Address: 2711 S. Loop Drive, Suite 4700, Ames, IA 50010-8664

Phone: 515-294-8103
FAX: 515-294-0467


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