ABSTRACT
The most important types of fossil oils are extracted directly from
subterranean reservoirs, as crude oil and natural gas. Fossil oils can
also be extracted from coal or from oliferous slate or clay.
The refining process is the starting point for many products used in
the building industry (Table 9.1). Heavy distillates including tar and
asphalt are used directly, mostly for making roofs and joints watertight.
Other, more refined, products provide raw materials for a whole spec-
trum of commodities: glues, waxes and solvents for paints. Fossil oils
are also the raw material for most plastics. The plastics industry has
developed explosively over the past half century. By 1971 an average
apartment contained about 1 ton of plastic. A modern Scandinavian
apartment contains 2 to 3 tons of plastics (Plastic Industries of Den-
mark), in everything from the sheathing on electric cables to floor
finishes and window frames (Table 9.2). The building industry uses
25% of all plastics produced.