Code	Occupation Description (1980)	Total # Employees (Male & Female)	Total # Female Employees
224	CHEMICAL TECHNICIANS	2,228	356
453	JANITORS AND CLEANERS	922
516	HEAVY EQUIPMENT MECHANICS	211
549	NOT SPECIFIED MECHANICS AND REPAIRERS	386
563	BRICKMASONS AND STONEMASONS	3,759
565	TILE SETTERS, HARD AND SOFT	5,655
585	PLUMBERS, PIPEFITTERS, AND STEAMFITTERS	2,072
595	ROOFERS	2,593
737	MISCELLANEOUS PRINTING MACHINE OPERATORS	112
755	EXTRUDING AND FORMING MACHINE OPERATORS	123
756	MIXING AND BLENDING MACHINE OPERATORS	2,005
759	PAINTING AND PAINT SPRAYING MACHINE OPERATORS	144
764	WASHING, CLEANING, AND PICKLING MACHINE OPERATORS	95
777	MISCELLANEOUS MACHINE OPERATORS, N.E.C.	1,625	169
783	WELDERS AND CUTTERS	2,065	5
804	TRUCK DRIVERS, HEAVY	268
869	CONSTRUCTION LABORERS	3,862	5
887	VEHICLE WASHERS AND EQUIPMENT CLEANERS	61
TOTAL		28,186	536

*(1) The estimates for each occupation apply across the surveyed industries in which the agent was observed. Not all industries were surveyed, and not all agents were observed in all surveyed industries. (2) When using the estimates, standard errors associated with estimates should be considered. (3) Potential exposures to a chemical agent are categorized as actual (i.e., the surveyor observed the use of the specific agent) or tradename (i.e., the surveyor observed the use of a tradename product known to contain the specific agent). The estimates presented in the table combine both categories.