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ANTI-STATIC
FLOORING OVERVIEW
As the installer of new
technological advances in the field of anti-static coatings and overlays,
the following information is presented to provide the elementary knowledge
needed to understand, specify, and install the newly developed products.
Whether your restoration needs call for a 6 mil anti static sealer or a
quarter inch overlay system, EP Floors has the products to achieve all your
specified needs. Even more important is the certainty that these products
are not surface modified coating systems; the same technology that makes
them work, will not wear off or degrade with time. Once installed, these
products provide permanent anti-static properties for the lifetime of the
coating system. Now you can beautify while you protect with colors ranging
from pastel grays to deep vivid blues, reds and greens. We even offer
semi-transparent one coat sealers to meet the challenges of any environment.
ELECTROSTATIC CHARGES:
Electrostatic charges can be induced from friction between two different
kinds of material (between two non conductors or simply by common surface
contact). Such charging takes place readily when most flooring material is
walked on or driven over and these discharges can often be accompanied by
sparks. As everyone is aware, in some industries, sparks can have
devastating consequences. This hazard can be eliminated if our anti-static
flooring system is the choice of the specifying engineer. These products
meet the requirements of electrical conductivity as well as a high
resistance to chemical attack and are designed for applications in such
places as laboratories, chemical plants, painting manufacturers and anywhere
where solvents are used. Additionally, some industries such as the computer
trade, require anti-static coatings for protecting sensitive electrical
components from failure. When all else has failed, you will find that the
use of the EP Floors product line will not be a shocking experience.
LEAKOFF
OF ELECTROSTATIC CHARGES:
The electrical discharge capacity of synthetic resin flooring is determined
by measuring the ohmic resistance. As a rule, floors with a leakage
resistance of 10+6 ohms are considered to be electrically
conductive. However, each country has its own standards for how they rate
this discharge capacity. For instance DIN 51953 applies in Germany, UL 779
applies in the United States
and the British standard is 3398. However, many engineers have requirements
far below those that are certifiable by organizations such as the
Underwriters Laboratories, depending on the protection needed for their
prospective environments. Although it is widely recognized in the industry
that less than 109 ohms of resistance is considered to be
anti-static, the majority of our systems far surpass those requirements. As
a matter of fact, the majority of our systems will provide anti-static
characteristics in the range nearing that specified for UL certification. UL
certification requires a discharge capacity of <1,000,000 ohms (10+6
ohms resistance) for conductive certification.
OUR
NUMBERS AND WHAT THEY MEAN:
*For our ESD144C/324C our
resistance average as tested = 1.72e+6
*For our ESD145CP sealer
our resistance average as tested = 1.80e+5
*1.72e+6 ohms = 1.72 x 10+6
ohms = 1,720,000 ohms
*1.80e+5 ohms = 1.80 x 10+5
ohms = 180,000 ohms
*Tested on a 4'x4'
plywood panel with spacing from 1-4 feet.
The Underwriters
Laboratories standard specifies:
*<1.0e+6 ohms
or <1.0 x 10+6 ohms or <1,000,000 ohms
* testing to be done on
4'x4' plywood panel at three feet.
SOME
THINGS YOU SHOULD KNOW:
*Concrete is conductive because of the moisture content present in the
concrete. However, the moisture content can be highly variable. That is why
a primer such as our ESD142, ESD144C, ESD145CP or ESD163CP must be used to
achieve proper anti-static characteristics below 1.0e+9 ohms. The
primer increases the conductivity by decreasing the ohmic resistance.
Although the ESD324C has anti-static characteristics, the full potential is
not achieved without an appropriate primer.
SO HOW DO WE KNOW WHAT NUMBERS ARE THE BEST ??
First, the best possible conductive floor would be a metal floor such as
copper. The ohms of resistance for a metal floor would be zero. Thusly the
numbers could be viewed as follows.
RATING FLOOR STATUS
RESISTANCE (ohms)
----------------------------------------------------------------------------------------------------------------
best
conductive 0.0 ohms
very
good conductive
>zero but <1.0x106 (0.0 to 1,000,000)
good
anti-static >1.0x106 but
<1.0x109 (1,000,000 to 1,000,000,000)
poor not
rated >1.0x109 (>
1,000,000,000)
Finally, it should be
pointed out that grounding the anti-static conductive system does improve
the performance of the system by decreasing the ohmic resistance and charge
buildup. The conductive primer is the product that should be grounded and
not the topcoat or any underlayment placed prior to the primer. This is
easily accomplished by grounding the coating with strips of copper or
grounding straps connected to a water pipe or neutral conductor in the
electric wiring system. Two earthing points normally suffice for a single
room. One ground point per 200 square meters of floor space is the general
rule for large areas when all individual slabs are connected with conductive
copper strips or tape.
RESTORING ANTI-STATIC
CHARACTERISTICS: However, for the same
reasons that make the conductive primers work, the conductive primers can be
used over a non-conductive overlay such as our ESD120/ESD94 power troweled
formula to impart significant anti-static properties. This allows the
installation of high build concrete restoration that would reduce the ohmic
resistance of the concrete substrate to an often acceptable level of ohmic
resistance. For instance: ESD120 (natural) power troweled, topcoated with
ESD95, then coated with ESD145CP and ESD183C will provide anti-static
performance.
Generally speaking, when
an anti-static system is placed over a non-anti-static coating system, the
numbers (ohms of resistance) will increase by a factor of about 10 to 100.
This means that a system that had customarily been tested over concrete at
1,000,000 ohms will yield a system of about 10,000,000 to 100,000,000 ohms (ie,
will go from 1.0x106 to between 1.0x107 ohms and
1.0x108 ohms).
RECOAT TIMES:
It has been ascertained that recoat times can affect the overall floor
resistance. All of our conductive primers have shown a tendency in some
applications to not reach the full resistance potential until 20-24 hours
after application. This in turn can affect the overall performance for the
complete system. In standard applications over concrete, the primers have
developed good resistance characteristics long before 24 hours; however,
when the primer is placed directly on a non-porous substrate, the cure times
to reach full resistance can be in the 20-24 hour range. Based on our
findings, we have not listed a recoat time on the technical data. Instead we
have instructed the user to not topcoat the conductive primer until the
electrical resistance is 106 ohms of resistance or lower. In some
instances it will require up to 24 hours for the primer to reach proper
conductivity before topcoat placement can begin. It is best to test the
primer before topcoating as this will eliminate any chances for a system
failure. If testing equipment is not available, then it would be advised to
wait 24 hours before recoating. In all testing, we have found the material
to be within the established parameters within the 24 hour time period at
normal room temperatures. 
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