Scale and Scope of Safety Assessment Methods in the Project Development Process

LONG DESCRIPTION:

Equations and notes for calculating adjusted total crashes per year and adjusted fatal and injury crashes per year.

The predicted average crash frequency is:

N_{predicted int} = N_{spf int} x C Note: Reduced HSM equation

Calculations and notes for adjusted total crashes per year:

N_{predicted int (Roundabout #1-Total)}= 4.50×0.89=4.01 Note: Predicted Total Crashes -- #1

N_{predicted int (Roundabout #2-Total)}= 9.24×0.89=8.22 Note: Predicted Total Crashes -- #2

N_{predicted int (Roundabout #3-Total)}= 7.70×0.89=6.85 Note: Predicted Total Crashes -- #3

Calculations and notes for adjusted fatal and injury crashes per year:

N_{predicted int (Roundabout #1-FI)}= 0.35×0.93=0.33 Note: Predicted FI Crashes -- #1

N_{predicted int (Roundabout #2-FI)}= 0.62×0.93=0.58 Note: Predicted FI Crashes -- #2

N_{predicted int (Roundabout #3-FI)}= 0.54×0.93=0.50 Note: Predicted FI Crashes -- #3

FI = fatal and injury. HSM = Highway Safety Manual.

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