A nozzle assembly, for a metal casting apparatus selected from a sliding gate and a tube exchange device, comprises a first refractory element comprising a first coupling surface which includes a first bore aperture, and a second refractory element comprising a second coupling surface, which includes a second bore aperture, the first and second elements being coupled to one another in a sliding translation relationship through their respective first and second coupling surfaces such that the first and second bore apertures can be brought into and out of registry to define, when in registry, a continuous bore for discharging molten metal from a molten metal inlet to a molten metal outlet of said nozzle assembly. A sealing member is provided between the first and second coupling surfaces of the first and second elements. The sealing member comprises a thermally intumescent material.

A fire-stopping material in a panel for an interior building wall is provided. The fire-stopping material includes a resilient, porous material at least partially impregnated with an intumescent agent.

A fire-stopping material in a panel for an interior building wall is provided. The fire-stopping material includes a resilient, porous material at least partially impregnated with an intumescent agent. A method of providing a service penetration through an internal building wall having fire-stopping material therein.

The invention relates to a potting paste composition for honeycomb reinforcement having improved fire retardancy characteristics. The potting paste composition comprises (a) a curable polymer; (b) a curing agent for the curable polymer; (c) a fire retardant comprising an ammonium polyphosphate in combination with an ingredient selected from the group consisting of metal hydroxides, expandable graphites, liquid phosphate esters, phosphorous organic compounds or salts thereof, and zeolites; and (d) a filler selected from the group consisting of polymeric microspheres, hollow glass microspheres, and thixotropic fillers; wherein the potting paste has an uncured density determined by the method according to EN ISO 1183 of not more than 0.7100 g/cm.sup.3, preferably of at most 0.680 g/cm.sup.3, more preferably of at most 0.673 g/cm.sup.3, still more preferably of at most 0.660 g/cm.sup.3, even more preferably of at most 0.658 g/cm.sup.3, yet more preferably of at most 0.653 g/cm.sup.3 and in particular of at most 0.620 g/cm.sup.3; and wherein the total content of the fire retardant is at least 5.0 wt.-%, preferably at least 10 wt.-%, more preferably at least 15 wt.-%, relative to the total weight of the potting paste composition.