Fire Department Access, Part 4: Traffic Calming Devices

As discussed in Code Red Consultant’s prior Insights on fire department access, roadway dimensional criteria, proximity to buildings as well as materials and maintenance of the roadways are critical to the design and longevity of a project to ensure responding apparatus can access a site.  This week’s blog will address the impacts of traffic calming devices to fire department access.

Traffic calming devices are commonly used when the traffic pattern of a particular area is not conducive to the nearby residential, recreational, or retail land uses. These devices are designed to reduce speed, increase driver focus, and in some cases encourage drivers to seek alternative routes, to enhance pedestrian, cyclist, and local traffic safety. Traffic calming devices can include the following measures:

  • Narrowing of roadways, such as reducing lane width, allowing on street parking, or converting one-lane roadways to two-lane roadways. These measures ensure that slower speeds and more attentive driving is necessary.
  • Vertical deflection, such as speed humps, speed bumps, speed tables, rumble strips, and raised pedestrian walkways. These deflections cause discomfort for drivers, and can cause damage to larger vehicles if traveling at significant speeds.
  • Horizontal deflection, such as chicanes. These deflections require drivers to swerve slightly, promoting more attentive and slower driving.

The major drawback to implementing traffic calming devices relates to first responder access. The primary concerns of the response community are timely arrival to an incident scene, with all emergency vehicle occupants arriving safely. Devices or strategies designed to slow the speed of traffic can greatly reduce response time, and can even cause damage to larger vehicles such as fire engines and ladder trucks. A 1995 study by the Portland, Oregon Bureau of Fire, Rescue, and Emergency Services tested the response times for 6 different sized fire vehicles at a various response speeds vs. common traffic calming devices (https://nacto.org/wp-content/uploads/2012/06/City-of-Portland-1996.pdf ). The study produced the following range of delays:

  • 14-foot speed bumps: 1.0 to 9.4 seconds of delay per bump
  • 22-foot speed bumps: 0.0 to 9.2 seconds of delay per bump
  • Traffic Circle: 1.3 to 10.7 seconds of delay per circle

NFPA 1141, Standard for Fire Protection Infrastructure for Land Development in Wildland, Rural, and Suburban Areas outlines requirements for traffic calming in relation to fire department access. Section A.5.2.18 states that “prior to installation of traffic calming, the authority having jurisdiction should work with the emergency response department(s) to ensure traffic calming devices can be negotiated by emergency response vehicles in a safe and timely manner without damage to those vehicles”. This requirement is echoed in 527 CMR 1.00, requiring AHJ approval for any traffic calming devices.

In response to the negative impact on first responder access, new traffic calming devices have been developed with easier passage for emergency vehicles in mind. These include speed tables and speed humps with gaps that line up with fire engine tire width.

While devices like these exist, it is important to ensure that coordination with the local emergency response agencies is paramount. Being cognizant of the needs, operating procedures, and equipment of the local fire department will ensure that a strategy is implemented that both increases pedestrian safety from traffic but also ensures little to no impact on response times of first responders.

This completes are blog series on fire department access.  We hope you found the content informative and will consider it a resource for future project planning. If you have questions on fire department access compliance, please reach out to our office at info@crcfire.com to find out how we can assist.

Click the links below to view the other Insights in the FD Access series:

Introduction

Part 1 Roadway Dimensions

Part 2 Roadway Materials and Maintenance

Part 3 Proximity to Buildings

Application of any information provided, for any use, is at the reader’s risk and without liability to Code Red Consultants. Code Red Consultants does not warrant the accuracy of any information contained in this blog as applicable codes and standards change over time. The application, enforcement and interpretation of codes and standards may vary between Authorities Having Jurisdiction and for this reason, registered design professionals should be consulted to determine the appropriate application of codes and standards to a specific scope of work.