Safety Analysis Methods & Resources
FDOT's Safety Crash Data Guidance
Apply this process when a safety analysis is needed on any project or location on the State Highway System. The process can also be applied to the off-system roadway network.
Based on Historic Crashes and Trends
Location Specific Analysis Specific location safety analysis determined by:
| Systemic Analysis Broader network analysis of data to determine where safety improvements are needed:
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Based on Safety Performance
Predictive Analysis Risk based approach to systemically analyze safety performance of roadways:
Click here to access Safety Data Analysis and Mapping tools.
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AASHTO’s Highway Safety Manual (HSM) is the guidance document for incorporating quantitative safety analysis in the highway transportation project planning and development processes to inform the highway transportation decision-making process.
The HSM includes guidance on:
- Human factors and the fundamentals of traffic safety
- The roadway safety management process (including information relevant to FHWA’s Highway Safety Improvement Program requirements and project planning), including:
- Network screening (identify sites with potential for crash or severity reduction
- Site assessment (diagnosis, countermeasure selection, economic appraisal
- Project prioritization
- Safety effectiveness evaluation
- Predictive methods for infrastructure improvement project alternative analysis and development/design, including:
- Use of national safety performance functions (models) developed to predict crashes by severity specific facility types and base conditions
- Associated crash modification factors (CMFs) to estimate the potential effects of design alternatives or changes from base conditions
FDOT HSM Resources & Tools
HSM Part B: Roadway Safety Management Process
Network screening resources on this page include:
- Safe Strides 2 Zero (SS2Z) – conducting an annual
screening of signalized intersections on the SHS.
Identifies high crash signalized intersections and is
shown in the Safety Assessment Dashboard.
- 2020 Pedestrian & Bicycle Network Screening –
a risk-based evaluation of pedestrian and bicycle safety
on the SHS utilizing roadway characteristics and ped and
bike demand characteristics. Results are available on eTraffic.
FDOT Safety Assessment Dashboard
The Safety Assessment Dashboard enables FDOT project scoping staff to incorporate safety needs into any work program project. The Dashboard consists of the Traffic Operations' Statewide Safety Initiatives and the over-lapping safety needs priorities identified by each district.
HSM Part C: Predictive Method
The HSM Part C provides a predictive method for estimating expected average crash frequencies at individual sites. This method relies on safety performance functions (SPF) that estimate predicted average crash frequency as a function of traffic volume and roadway characteristics (e.g., number of lanes, median type, intersection control, number of approach legs).
FDOT Intersection Control Evaluation (ICE)
The ICE process quantitatively evaluates several intersection control scenarios (alternatives) and ranks these alternatives based on their operational and safety performance. Implementing a “performance-based” procedure such as ICE creates a transparent and consistent approach to consider intersection alternatives based on metrics such as safety, operations, cost, and social, environmental, and economic impacts. ICE resources on this page include:
• FDOT ICE Tool
FDOT HSM Spreadsheet Tools & Crash Cost Calculations
• For data collection, use MUTS Forms 750-020-06a to 750-020-06c
Work Under Development
Project Safety Analysis - Initiating the development of Florida based Safety Performance Functions (SPFs) and Crash Modification Factors (CMFs) for intersections in context classifications C3R, C3C and C4.
Safe System Intersection (SSI) Analysis - Initiating the development of a process to use the SSI index for crash prediction.
Crash Modification Factors
Crash Modification Factors (CMFs) quantify the expected change in average crash frequency as a result of geometric or operational modifications to a site that differs from set base conditions. The Crash Modification Factor Clearinghouse currently houses over 3,500 CMFs.
Crash Modification Factor Clearinghouse
How to Use Crash Modification Factors
The CMFs that meet the HSM inclusion criteria are identified as such in the Clearinghouse. Many state DOTs have developed a listing of the preferred CMFs for use on projects within their jurisdiction. Several state examples are provided in the Clearinghouse, but users should contact the DOT safety engineer for guidance on appropriate CMFs for use on projects in their jurisdiction.
FDOT HSM Training
The following training modules are made available from the FDOT Design Office.
HSM Webinar 1 - Introduction to HSM & Fundamentals
HSM Webinar 2 - Roadway Network Screening
HSM Webinar 3 - Crash Modification Factors (CMF)
HSM Webinar 4 - Two Lane Rural
HSM Webinar 5 - Multi-Lane Rural
HSM Webinar 6 - Urban and Suburban
HSM Webinar 7 - Freeways
HSM Webinar 8 - Ramps
HSM Webinar 9 - Benefit/Cost Analysis
Other HSM Resources
FDOT Highway Safety Manual User Guide 2015
Highway Safety Manual - Homepage (AASHTO)
Interactive Highway Safety Design Model (IHSDM) (FHWA)
Thank you to FDOT District One for portions of this page content, adapted from the Safety Academy.
Page updated : March 8,2023