A flexible fire resistant innerduct structure is configured to contain a
cable within a conduit. The innerduct structure includes a pair of
adjacent strip-shaped layers of flexible material that are joined along
their longitudinal edges to define a channel through which the cable can
extend longitudinally through the innerduct structure between the layers.
The adjacent layers have differing widths between their longitudinal
edges, whereby the wider layer bulges away from the narrower layer to
impart an open configuration to the channel. Other features of the
innerduct structure relate to the material of which it is formed. Such
features includes the structure of the material, such as a woven
structure, and further include properties such as melting point, tensile
strength, fire resistance, elongation, coefficient of friction, crimp
resistance and compression recovery.
