What is a Roundabout?

A roundabout is a type of circular intersection, but is 

quite unlike a neighborhood traffic circle or large rotary. 

Roundabouts have been proven safer and more efficient 

than other types of circular intersections. 

Roundabouts have certain essential distinguishing features: 

• Counterclockwise Flow. Traffic travels

counterclockwise around a center island.

• Entry Yield Control. Vehicles entering the roundabout

yield to traffic already circulating.

• Low Speed. Curvature that results in lower vehicle 

speeds (15-25 mph) throughout the roundabout.

FHWA identified roundabouts as a Proven Safety 

Countermeasure because of their ability to substantially 

reduce the types of crashes that result in injury or loss of life. 

Roundabouts are designed to improve safety for all users, 

including pedestrians and bicycles. They also provide significant 

operational benefits compared to conventional intersections.

Cover photo sources, top to bottom: Jeff Shaw, FHWA; Brad Estochen, MnDOT;

Jeff Young, McHenry County Highway Department

ROUNDABOUTS

& First Responders

Saving Lives Together

To learn more about roundabouts, please visit:

safety.fhwa.dot.gov

Publication number FHWA-SA-14-098 Updated July 2020

Circulatory

roadway

Counterclockwise

circulation

Accessible

pedestrian crossing

Splitter Apron

island

Pavement

Markings at Entry

Landscape

buffer

Bicycle lane

treatment

Central

island

Sidewalk or

shared use

path

Figure 1. Modern Roundabout Schematic

On average, roundabouts reduce severe crashes – 

those resulting in injury or loss of life – by 78-82%1

1 Highway Safety Manual, American Association of State Highway and Transportation 

Officials, Washington, DC, 2010.

Educational Resources

Wisconsin Guidance on Reacting to

Emergency Vehicles in Roundabouts

https://wisconsindot.gov/Documents/safety/

safety-eng/roundabouts/br-emergencyveh.pdf 

Minnesota DOT Roundabout Animation

www.dot.state.mn.us/roundabouts/emergency.html

Washington State DOT Videos on

Roundabouts and How to Drive Them

https://www.youtube.com/watch?v=P3k65uS5-EE

http://www.youtube.com/watch?v=MywmtskFiiI 

British Columbia MOT Video on Navigating a

Roundabout with Emergency Vehicles

https://www.youtube.com/watch?v=Tk9n1uVa8LE

StrengtheningPartnerships

Incorporating EMS into Strategic

Highway Safety Plans

http://safety.fhwa.dot.gov/hsip/shsp/ems/connection/

For More Information

Jeffrey Shaw, P.E., PTOE, PTP

FHWA Office of Safety

2 0 2 .7 3 8 . 7 7 9 3 or jeffrey.shaw@dot.gov

Hillary Isebrands, P.E., PhD

FHWA Resource Center

7 20. 5 45.4367 or hillary.isebrands@dot.gov
Designing for First Responders

Roundabouts are not designed to inhibit traffic. Rather, 

they are optimized for the safety and efficiency of all users. 

Roundabouts can be designed for large trucks, including 

a special purpose apparatus such as a ladder truck. This is 

accomplished by using features such as:

• Wider entry and exit lanes for efficient movement of

traffic through the roundabout.

• Mountable aprons and curbs intended for use by

vehicles with a wide and/or long wheelbase.

• Curvature and radii that allow for easy turning 

movements, including u-turns.

“Before the first roundabout was 

constructed in our city, our station 

arranged to visit one nearby so that 

we could experience it firsthand. That 

answered a lot of questions and helped 

build confidence in roundabouts.”

- Brad Estochen

Minnesota DOT Safety Engineer &

Firefighter and EMT for the City of Woodbury

Frequently Asked Questions

When the first roundabout in a community is proposed, 

it is natural for first responders to have questions and 

concerns. Several of the most common questions are 

addressed below:

Q: Will all our vehicles be able to maneuver

through a roundabout?

A: Roundabouts work for many types of large vehicles. 

Partnering with the road agency to conduct a “test drive” 

(laying out the roundabout in a large open area using 

cones and temporary devices) can help evaluate and 

influence the design.

Q: What about emergency response times?

A: At any intersection, traffic conditions vary throughout 

the day. Roundabouts can actually improve travel times 

by eliminating unnecessary stops and delays. Furthermore, 

the IAFF and other public health and safety organizations 

recognize that small differences in travel times rarely, if ever, 

impact incident or patient outcomes.3,4

Q: How will drivers in our community know how to 

react to approaching emergency vehicles?

A: In this way, roundabouts are no different from other 

intersections – drivers must clear the intersection, pull 

off to the right, and let the emergency vehicle pass. To 

help educate drivers, there are many excellent resources 

available from states and cities where roundabouts are 

common. First responders can contribute to general 

roundabout education and outreach in a community 

by helping explain to the public how to react when an 

emergency vehicle approaches.

Q: Why consider roundabouts when we have traffic 

signal preemption in our city?

A: The use of preemption devices at signalized 

intersections remains a worthwhile option. However, in 

addition to being safer, roundabouts are viable in many 

places where traffic signals are not. Furthermore, even 

where signal preemption is used, first responders must 

obey state laws and department policies, and proceed 

cautiously – likely at speeds comparable to a roundabout.

Shared Mission – Shared Benefits

Saving lives and preventing serious injuries are the highest 

priority of both first responders and highway agencies. 

Roundabouts are safer intersections that result in fewer 

severe crashes requiring emergency response. 

Safer intersections are important for first responder 

occupational safety and health, too. Studies show that 

most fatalities resulting from a crash involving a fire truck 

occur at, or are related to, an intersection. Further, angle 

crashes are the most common fatal crash type involving fire 

trucks.2

 The International Association of Fire Fighters (IAFF) 

and others cite intersections as high risk locations for all 

emergency response disciplines.3 

Roundabouts are also a very efficient type of intersection. 

They do not have the same stop-and-go conditions as 

traditional intersections.

• Roundabouts keep people moving, but at speeds

where injury risk is greatly reduced.

• Roundabouts can reduce or eliminate lines of stopped 

traffic typical of stop signs and traffic signals, making 

them easier to navigate throughout the day and night.

• Unlike traffic signals, roundabouts don’t depend on

electricity to function, so they are not susceptible to 

power outages.

1 Highway Safety Manual, American Association of State Highway and Transportation Officials, Washington, DC, 2010.

2 Campbell, K.L., Traffic Collisions Involving Fire Trucks in the United States, UMTRI-99-26, Ann Arbor, MI: University of Michigan Transportation Research Institute, 

Ann Arbor, MI, 1999

3 International Association of Fire Fighters (IAFF), Best Practices for Emergency Vehicle 

and Roadway Operations Safety in the Emergency Services, Washington, DC 2010

4 Bailey, E.D., Sweeney, T., Considerations in Establishing Emergency Medical Services 

Response Time Goals, National Association of EMS Physicians, Lenexa, KS, 2003

Source: Howard McCulloch, NYSDOT

Source: Jeff Young, McHenry County Highway Department

Source: Brad Estochen - MnDOT