dynes cm this will minimise the tendency of a wet roller acting on a loose fibrous surface to drag off fibers and particles by the surface tension of the liquid film between the roller surface and the wetted material reduction of this drag is further achieved by a foaming action to the formulation this leads to foam generation by the squeezing action of the roller on a porous resilient layer containing both air and the applied liquid such foam has less drag than a liquid film against the separation of the roller to maximise saturation of the layer of insulation the viscosity of the applied binder should be as low as possible and in any case less than 100 cps further the binder is required to have a pronounced surfactant wetting action on fine fiber and dust having the surface characteristics of asbestos and fiberglass when dry the film of cured binder must have the following indices of flammability as per test method of as1530 prt 3 1976 ______________________________________ a for deep impregnation b for final coat only with of exposed surface finishing or for deep impr outer coating in flammableindex as1530 pt 3 of b situations______________________________________ignitability 0 20 less than 14 less than 1 0spread of flame 0 10 0 0heat evolved 0 10 less than 3 5 0smoke developed 0.