materials (types and thickness) are uniformly distributed around
its neutral axis.
Symmetrical Insulating Glass Unit: an insulating glass unit
which has lites of equal thickness and identical heat treatment.
Temper: the degree of residual stress on annealed glass measured
polarimetrically or by polariscopic comparison with a standard
such as one or more strain disks.
Tempered Glass: glass that has been subjected to a thermal
treatment characterized by rapid cooling to produce a
comparatively stressed surface layer. See "Fully Tempered Glass"
and "Heat Strengthened Glass."
TNT-Equivalent Weight: the weight of a particular explosive
which produces an explosion similar to 1 pound of TNT.
Tool Mix: group of tools and explosives used in forced entry
attacks. Qualifying tool categories for each design basis threat
severity level are specified in Table D-30.
Urethane, Aliphatic: thermoplastic interlayer required to bond
polycarbonate lite to polycarbonate or glass lite.
Venting: the relief of overpressure in confined volumes through
the release of air to a larger volume. An open window helps to
vent an explosion.