(a) Except as otherwise provided in this chapter, no employee may be employed for a period that exceeds eight hours within any 24-hour period and the hours of employment of any workday shall be consecutive, excluding intermissions for meals, for all persons who are employed or engaged in work in any of the following:
(1) Underground mines.
(2) Smelters and plants for the reduction or refining of ores or metals.
(b) No provision of this chapter applies to quarries or other operations for the extraction of nonmetallic minerals, including, but not limited to, sand, gravel, and rock.
(c) No provision of this chapter applies to an employee who is employed in an executive, administrative, or professional capacity, or employed as an outside salesperson.