requires grease, oil, and other lubricants. Field sanitation teams, engineers, and
preventive medicine personnel handle insecticide concentrates. Additional examples of
operations involving the use of liquid chemicals can be found in Appendix B.
b. Liquid Chemicals as Vapors. Most organic compounds can be vaporized
very easily; in fact, some vaporize at room temperature. A common exposure involving
chemical vapor occurs in vapor degreasing of metal parts. When metal machine parts
are removed for repair or cleaning, their lubricating oils and greases must be removed.
This is often accomplished by immersing the parts in the vapor of solvents which, when
contained in open top containers, will evolve various amounts of vapor, depending upon
the type of solvent and its temperature.
c. Liquid Chemicals as Mists. Liquid chemicals can be changed into a fine
mist by passing the compound through an appeture such as a spray-painting nozzle.
A common example of this process is spray painting. Spray painting is widely used in
vehicle repair shops, machinery maintenance facilities, and building construction and
maintenance. Paint contains many organic compounds that make up the pigment,
binders, thinners, wetting agents, and solvents.
2-12. BODILY EFFECTS
a. General. The bodily effects of liquid chemicals vary widely, depending on the
exact chemical involved. The effects on the skin, nervous system, liver, and those
leading to cancer will be discussed in this subcourse.
b. Skin Diseases. In terms of numbers, occupational skin diseases (dermatitis)
are by far the most important of the occupational diseases. Although occupational skin
conditions may cause considerable loss of time from work, they are not usually severe
enough to cause permanent disability.
(1) The healthy skin has certain barriers against injury. The dead surface
cells resist most chemicals, while the oily secretions of the skin form a protective
covering against some chemicals. Deeper skin cells prevent the loss of water from the
(2) The occurrence of occupational dermatitis depends mainly on the
specific chemicals to which the skin is exposed and the length of the exposure. The
presence of other skin diseases lowers resistance to exposure. Personal cleanliness is
important, since failure to wash the skin or to remove dirty clothing increases the length
of exposure. The type of skin is an important factor, too. People with oily skins are
more likely to develop infected sweat glands; where as those with dry skins are more
affected by drying agents such as detergents. Male workers have more skin disease
than do female workers, possibly because females take better care of their skin. There
is more skin disease in the summer than in the winter because of the fact that less
clothing is worn and to the presence of sweat.