Gardening Articles: Landscaping :: Lawns, Ground Cover, &
Wildflowers Leaf Blowers Go Green (page 3 of 4) by National
Gardening Association Editors All hand-held blowers consist of a
small gasoline-powered engine (usually two-stroke) or electric
motor connected to a plastic fan that pulls in outside air and
forces it through a small-diameter tube at high velocities. This
velocity is measured two ways: in cubic feet per minute (cfm)
and miles per hour (mph). Cfms can be measured at different
points resulting in different numbers. (In the listing of
various blower-vacs below, the cfms are measured conservatively
in the "pipe," "tube," or "blow-mode.") Some fans are side-
mounted, but on most newer models they are bottom-mounted, a
design feature that makes for an easier-handling machine because
there's no twisting action caused by the spinning fan.
Manufacturers of blower-vacs are highly competitive and tend to
make inflated claims about power and reduction ratio. For most
tasks, a 150-mph air velocity will serv