Rationale

This revision to E2579 is needed to ensure that mounting and testing fire-retardant-treated wood panel products impregnated with chemicals during manufacture (FRTW) are consistent with the performance required by the IBC building code for using FRTW as structural panels for any construction type. The code requires that FRTW wood structural panels “be tested with a ripped or cut longitudinal gap of 1/8 inch (3.2 mm)”, using the ASTM E84 test, “continued for a 20-minute period”, and there is no provision, neither in ASTM E84 nor in ASTM E2579, for doing that. An earlier ballot to revise ASTM E2579 already added that this mounting method is applicable for the 30-minute test (i.e., for ASTM E2768). The required “gap” is being proposed (as intended by the code language) to run longitudinally along the tunnel length, at the centerline of the test chamber. The word “centre-line” is being revised.