Specifications

Introduction
Containing the overspray and
keeping it out of the air and off
other objects is an important
consideration in a spray finishing
operation. This chapter discusses
various types of booths and details
periodic maintenance.
1. What is a spray booth?
A compartment, room or enclosure
of fireproof construction; built to
confine and exhaust overspray and
fumes from the operator and
finishing system.
There are various models available,
designed for particular spray
applications. Spray booths may be
partially enclosed (figures 1 & 2) or
totally enclosed (figure 3).
Consult the National Fire Protection
Association (NFPA) pamphlet #33
and the O.S.H.A. requirements for
construction specifications.
2. What are the benefits of a
spray booth?
A well-designed and maintained
spray booth provides important
advantages:
It separates the spraying operation
from other shop activities, making
the spraying, as well as the other
operations, cleaner and safer.
It reduces fire and health hazards
by containing the overspray.
It provides an area that contains
residue, making it easier to keep
clean. It also keeps both the
operator and the object being
sprayed cleaner.
In a booth equipped with adequate
and approved lighting, it provides
better control of the finish quality.
3. What types of spray booths are
there?
There are two; the dry filter type
and the waterwash type.
4. What is a dry filter type spray
booth?
This booth draws overspray-
contaminated air through
replaceable filters and vents the
filtered air to the outside.
It is the most common type of
booth for most industrial and
automotive applications.
It is used for spraying low-volume,
slower-drying materials, and is not
affected by color changes.
Figure 1 - Dry Filter Type Booth
5. What is a waterwash type
booth?
A waterwash booth actually
washes the contaminated
overspray air with a cascade of
water and traps the paint solids.
Fewer paint particles reach the
outside atmosphere to harm the
environment.
Waterwash booths are generally
used when spraying high volumes
of paint.
Figure 2 - Waterwash Industrial
Type Spray Booth
Figure 3 – Automotive Downdraft
Dry Filter Booth
6. What is an exhaust fan?
A typical exhaust fan consists of a
motor, a multiple blade fan, pulleys
and belts. It removes overspray
from the spray booth area
(see figure 4).
Contemporary exhaust fans are
carefully designed to prevent
overspray from coming into contact
with the drive mechanism.
Blades are made of non-sparking
metal, and they move the
maximum volume of air-
per-horsepower against resistance
such as exhaust stacks, filters, etc.
(See NFPA pamphlet #33.)
8. Spray Booths
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