Pour water into the ring at a rate sufficient
to maintain a head between the two marked lines. Use a total
of 3.60 6 0.05 kg [8.0 6 0.1 lb] of water. Begin timing as soon
as the water impacts the pervious concrete surface. Stop timing
when free water is no longer present on the pervious surface.
Record the amount of elapsed time to the nearest 0.1 s.