Code	Occupation Description (1980)	Total # Employees (Male & Female)	Total # Female Employees
519	MACHINERY MAINTENANCE OCCUPATIONS	31
549	NOT SPECIFIED MECHANICS AND REPAIRERS	215
613	SUPERVISORS, EXTRACTIVE OCCUPATIONS	335
614	DRILLERS, OIL WELL	5,362
617	MINING OCCUPATIONS, N.E.C.	3,346
757	SEPARATING, FILTERING, AND CLARIFYING MACHINE OPERATORS	338	123
779	MACHINE OPERATORS, NOT SPECIFIED	106
824	LOCOMOTIVE OPERATING OCCUPATIONS	3,346
856	INDUSTRIAL TRUCK AND TRACTOR EQUIPMENT OPERATORS	61
878	MACHINE FEEDERS AND OFFBEARERS	6,492
TOTAL		19,631	123

*(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.