ESD Tiles and sheet goods are designed to provide options in conductivity
for a static discharge rate suited to a multitude of environments. By far,
the most popular ranges are Static Conductive and Static Dissipative.
Generally speaking, for electronic manufacturing and other sophisticated
static control environments static conductive is now the preferred choice.
For non critical static control (such as hospitals) static dissipative may
be used. Both ranges cost about the same. Static dissipative flooring
doesn't provide ay particular set of advantages over static conductive
however static dissipative has been written into so many existing
specifications over the years it continues to be offered to the industry.
The more
conductive a flooring material is the faster the static charge will be
dissipated to ground. Should you require assistance in selection
of conductivity appropriate to your needs please contact United SCP for
immediate assistance.
Anti-Static Flooring: That was then,
this is now! Anti Static flooring was
a phrase coined by the flooring industry (circa 1959) used to describe
a flooring material that wouldn't allow a person (when walking on the
flooring) to generate enough
static to feel the discharge when they touched a grounded object
(like a light switch). Keep in mind a
person must generate over 3,000 volts to actually "feel" the discharge!
Now-a-days? Anti-static is used as a somewhat misleading catch all, generic
phrase to describe any flooring material that controls an electrostatic
discharge. The three following ranges of electrical conductivity
move the static charge from personnel to ground and are the
industry accepted standards for conductivity for true static control
floors.
HIGH CONDUCTIVITY: Does not meet industry accepted safety standards of a minimum
electrical resistance of >1.0E04. This material is recommended for use by
trained personnel ONLY and it is typically only used in specialty Military
and munitions manufacturing applications. Our High Con (for example) is such
a product. It is a solid black 2mm thick x 2 meter wide x 20 meter long sheet good static control
flooring vinyl with an electrical resistance range of <1K ohm.
STATIC CONDUCTIVE:
Meets all minimum safety requirements for electrical conductivity of >1.0E04
(as measured in ohms) yet falls in what is termed the "static conductive"
range of <1.0E06 when tested to ANSI/ESD S7.1 and <3.5E07 when tested to
ANSI/ESD 97.1 (combination resistance of technician in esd heel straps and
flooring to ground). This range of conductivity provides easy (TR 53)
compliance to the latest specifications of ANSI/ESD S 20.20-2007 (the most
recent requirements for static control in electronic manufacturing
environments.
STATIC DISSIPATIVE: Static
dissipative flooring materials have a specific electrical
resistivity (when tested to S7.1 protocol) of greater than 1.0E06 but below
1.0E09 (as measured in ohms. Static dissipative vinyl flooring is manufactured via 2
methods. Either a vinyl material is loaded with a conductive element
(as is the case of Forbo
and VPI flooring) OR the material
is manufactured without the conductive elements but with hygroscopic
capabilities. These hygroscopic capabilities allow the flooring to absorb
ambient humidity thus rendering the material slightly conductive (aka static
dissipative). Static Dissipative flooring that contains conductive elements
typically falls in the range of 1.0E06 to 1.0E07, hygroscopic materials
typically fall in the range of 5.5E07 to slightly <1.0E09 @ 50%rH.
ElectraFloor static dissipative is a hygroscopic material. The lower
conductivity still drains electrostatic potential but at a slightly slower
speed. Nuisance static discharges from personnel to grounded objects are
eliminated (such is also the case with static conductive flooring). This
material is very useful in health care environments as well as electronic
manufacturing where high voltage power sources may present an electrocution
hazard to personnel.
Static dissipative and anti-static flooring may
present difficulties in obtaining combination resistance levels
(i.e. esd chair's, carts and trolley's with drag chains in
combination with the flooring) at electrical resistance levels
that meet industry accepted standards. HOWEVER static
dissipative floor can indeed do a very efficient job of
eliminating static from technicians. Many static dissipative
floors reduce a charge from a technician, walking on the floor
in heel straps to <14 volts! Why? Many times a floor's
ability to tribo charge is related more to flooring TEXTURE than
conductivity. The smoother a floor, the easier for it to build
up a charge on technicians. United Flooring marked as
anti-slip has the added benefit of a sizeable reduction in
personal tribocharging characteristics.
