Specifications

20
Environmental Factors
The ability of the touch system to
withstand environmental conditions is an
important factor when evaluating touch
technologies.
Sealability
Sealability is the ability to seal a touch
system, including display electronics, from
dirt, liquids, etc. If the system is going to be
located in an area where contaminants are
present, sealability can be an important
consideration. In environments such as
surgical operating rooms, sealability is
critical.
All touch technologies can be sealed to
meet NEMA 12 requirements that a system
be operational after accidental splashing or
cleaning.
Capacitive overlay, guided acoustic
wave, resistive overlay, near field imaging
and scanning infrared technologies can be
sealed to meet NEMA 4 requirements, which
require a system to operate, even after
exposure to hose-directed water.
Durability and Resistance to Vandalism
Durability is the ability to withstand
millions of touches over many years.
Resistance to vandalism is the ability to
resist defacement - scratching, breaking,
theft, etc.
Dust and Dirt
An excessive buildup of dust, dirt, or
other contaminants can adversely affect the
performance of some touch technologies.
n Capacitive overlay, scanning
infrared, and surface acoustic wave
technologies will operate with low to
moderate accumulations of dust, dirt, and
other contaminants. Excessive levels will
affect performance.
n Guided acoustic wave, resistive
overlay, and near field imaging touch
technologies are not affected by dust, dirt, or
other contaminants.
Chemicals
All touch technologies are unaffected by
general purpose cleaning solutions.
However, some materials used in the various
touch technologies can be attacked by
certain chemicals.
n A resistive overlay touch system
has an exposed polyester overlay.
Chemicals that attack polyester should not
be used.
n A scanning infrared touch system
has exposed polycarbonate bezels.
Chemicals that attack polycarbonate, such as
petroleum-based chemicals, should not be
used. More resistant materials are available
for construction of special IR touch systems,
but unless specified, they are not widely
used.