During which conditions might the Free Flow Speed (FFS) be observed?

Free Flow Speed (FFS) refers to the maximum speed at which vehicles can travel under ideal conditions without being impeded by traffic. This condition is typically observed when there is low-volume traffic since a sparse flow of vehicles allows for smooth, uninterrupted movement.

Under low-volume traffic situations, the density of vehicles on the roadway is low enough that interactions between vehicles are minimal. As a result, drivers can maintain speeds that are close to the roadway's posted speed limit or design speed, experiencing little to no delays. This scenario contrasts sharply with peak hours, where congestion leads to slower speeds due to increased vehicle density and interactions.

Adverse weather conditions, such as rain or snow, can also reduce driving speeds due to safety concerns and decreased visibility, while heavy construction can obstruct roadways and limit available lanes, directly affecting traffic flow and speeds. Both of these situations would not support the conditions for Free Flow Speed. Thus, the ideal condition for observing Free Flow Speed is indeed during low-volume traffic situations.