While all perimeter joint protection is tested at its maximum joint
width, the maximum joint width of a static perimeter joint protection
is the same as its nominal joint width. This is another difference
between dynamic perimeter joint protection Listings and those
designated as “static”.
The dynamic perimeter joint protection is tested at its maximum
joint width, which is larger than the nominal joint width at which
the perimeter joint protection is installed. Many of the perimeter
joint protection systems consist of compressed insulation, which
increases its nominal density when installing into a perimeter joint
that is narrower than the nominal thickness of the insulation. In all
dynamic perimeter joint protection, the effective compression and
the effective density of the insulation decrease at maximum joint
width, which increases heat transfer through it creating a worse-
case ASTM E2307 fire test scenario.
No movement data is presented in static perimeter joint protection
Listings. The nominal joint width and maximum joint width are the
same for static perimeter joint protection, which is unrealistic for
perimeter joint applications. An unchanged (static) joint width means
that heat transfer through the insulation remains the same for their
nominal joint width and maximum joint width conditions. This is the
best-case fire test scenario. Static perimeter joint protection will
perform better than a dynamic perimeter joint protection that uses
the same nominal width and nominal density insulation because the
former does not experience a decrease in its effective compression
or effective density to be ASTM E2307 fire tested.
Some ASTM E2307 laboratory test frames are designed to
accommodate both horizontal and vertical movement cycling.
These test frames use hydraulics to cycle the dynamic perimeter
joint protection before the ASTM E2307 fire-resistance test is
conducted. The magnitude of expansion/ contraction movement
cycling for ASTM E2307 is determined by the test sponsors.
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