Figure 10-16.-Vane-axia1 fan: A. Exterior view. B. Cutaway view. C. Cutaway view of the fan motor.
Most portable fans are of the axial-flow type,
driven by electric, explosionproof motors. On ships
carrying gasoline, a few air turbine-driven
centrifugal fans are normally provided. You can
place greater confidence in the explosionproof
characteristics of these fans.
Never use a dc-driven fan to exhaust air that
contains explosive vapor.
Many local exhausts are used to remove heat
and odors. Machinery spaces, laundries, and
galleys are some of the shipboard spaces where
local exhausts are used.
Most exhausts used on Navy ships are
mechanical (contain an exhaust fan), although
natural exhausts are sometimes used in ships
structures and on small craft.