Assertion: foam's form | /r/CapableOf | prevent water vapour
Facets:
value: from passing through the insulation
type: TRANSITIVE-OBJECT
Source sentences:
text: Condensation will not occur, provided that (a) the insulation surface is above the dewpoint temperature of the air; and (b) the insulation incorporates some form of water-vapour barrier or retarder that prevents water vapour from passing through the insulation to form on the pipe surface.