Guide to Understanding Effects of Raising Speed Limits
Over the past decade, there has been a trend toward higher speed limits, especially on rural
interstates and freeways. Eleven states have increased speed limits to 75 mph, with some of them
raising the limit as high as 85 mph on freeways and 75 mph on other roads.
The TRB National Cooperative Highway Research Program's
NCHRP Research Report 1006: Guide to Understanding Effects of Raising Speed Limits
provides a better understanding of the expected safety implications of increasing speed limits to
75 mph or higher.
Supplemental to the report are a
presentation and
NCHRP Web-Only Document 328: Safety Effects of Raising Speed Limits to 75 mph and Higher.
This Summary Last Modified On: 10/17/2022