The Crash Modification Factors Clearinghouse provides a searchable database of CMFs
along with guidance and resources on using CMFs in road safety practice.
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What are CMFs?

A crash modification factor (CMF) is used to compute the expected number of crashes after implementing a countermeasure on a road or intersection.

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NEWSLETTER

Hot off the press! The CMF Clearinghouse Update: Winter 2021 enewsletter is now available. Read for the latest on the Clearinghouse's additions and activities.

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Updated Ratings

The CMF Clearinghouse transitioned to the CMF rating criteria developed as part of the NCHRP 17-72 project for the 2nd edition of the Highway Safety Manual on February 15, 2021.

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RECEIVE THE QUARTERLY EMAIL NEWSLETTER

CMFs were last added to the clearinghouse on November 9, 2021.