Code	Occupation Description (1980)	Total # Employees (Male & Female)	Total # Female Employees
453	JANITORS AND CLEANERS	302
518	INDUSTRIAL MACHINERY REPAIRERS	2,418
519	MACHINERY MAINTENANCE OCCUPATIONS	96
613	SUPERVISORS, EXTRACTIVE OCCUPATIONS	335
614	DRILLERS, OIL WELL	7,333
783	WELDERS AND CUTTERS	101
785	ASSEMBLERS	954	88
889	LABORERS, EXCEPT CONSTRUCTION	1,714	454
TOTAL		13,254	542

*(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.