Glossary of Terms

The term describing the action of a coating or mastic when it cracks into large segments. When the action is fine and incomplete it is usually referred to as “checking”.

Insulation, of the flexible type, formed into sheets or rolls, usually with a vapour-barrier on one side and with or without a container on the other side.

Rounded elevation of the surface of a mastic resembling a blister on the human skin, usually the entrapment of air or vapour.

Rigid or semi-rigid, self-supporting insulation formed in rectangular shapes.

Rigid or semi-rigid insulation formed into sections, rectangular both in plan and cross section, usually 900 mm to 1200 mm long, 150 mm to 600 mm wide, and 25 mm to 150 mm thick.

A light, plain weave, coarse, cotton cloth with hard twisted yarns, usually not more than 271 g/m2 (8 oz. per square yard).

A liquid, or semi-liquid, protective finish capable of application to thermal insulation or other surfaces, usually by brush or spray, in moderate thickness, less than 0.76 mm.

The dimensional change with time of a material under load apart from, and following, the initial instantaneous elastic or rapid deformation.

An optional term for sheeting having nominal thickness not greater than 0.25 mm.

A transverse gap between layers of sheet materials caused by warping or bunching one or both layers.

In a coating application a place not covered by a coating compound.

A covering placed around an insulation to protect from mechanical damage, and, insofar, as it is intrinsically able, from weather, water, ultra violet light, etc.

Uneven surface of spray-applied coating, somewhat resembling an orange peel.

The incandescence, or glow, which lingers in some materials after any flame, or other evidence of fire, has departed.

Excessive flow in material after application to a surface, resulting in “curtaining” or running.

The formation of a relatively dense film on the surface of a mastic or coating material while stored in containers.