Smoke is an inevitable by-product of fires. We may think of it
as simply a dark cloud, but smoke also contains finely dispensed
liquids and gases. In fact, the most dangerous components of
smoke are the invisible gases present during the fire. After the
fire, the gases disperse but the smoke solids and liquids remain
on exposed surfaces. These deposits are more accurately called
"fire residues" than "smoke", because they are no longer the
same as the heated cloud generated by the fire. Fire residues
vary in character. Some appear as dry particles, others as
smeary flakes; still others are sticky and viscous. The type of
residue depends on the items that burned and their rate of
combustion. Smoke residues often emit obnoxious odors which
persist long after the fire. Questions of toxicity arise,
particularly when the odor is intense. Off - gassing from fire
residues may cause eyes to tear, particularly in confined
spaces. While no studies have been performed on the effects of
breathing fire residues after a fir