Question

Explain how Peak Hour Factor accounts for uneven flows

Answer 1

The Peak Hour Factor(PHF) compares the traffic volume during the busiest 15minutes of the peak hour with the total volume during the peak hour.It indicates how consistent traffic volume is during peak hour.

PHF=(total hourly volume)/[(peak 15-minute volume within the hour X4 )]

=V/(VpeakX4)

0<PHF>=1

A PHF of 1 indicates that the traffic volume in every 15-minute interval is the same and therefore the traffic flow is consistent throughout the hour.Lower PHF values indicate more variable traffic flows and that the traffic volume has a spike during the peak 15-minute interval.