OPINION OF THE COURT
RONEY, Circuit JudgeThis case questions which Government agency has jurisdiction over the safety practices in connection with handling and processing coal within an electric generating plant in Homer City, Pennsylvania. We affirmed a decision by the Federal *1503Mine Safety and Health Review Commission upholding the issuance of certain safety violation citations issued under the Mine Safety and Health Act against Pennsylvania Electric Company (Penelec). Penelec asserted that the Occupational Safety and Health Act (OSHA) should govern its practices and that the Mine Act inspector was without jurisdiction to issue the citations. Penelec filed a petition for rehearing which we granted in order that we might consider the arguments made therein.
Upon reconsideration, we again affirm the Federal Mine Safety and Health Review Commission, but on narrower grounds than set forth in our prior opinion. We affirm first, because the Penelec conveyor head drives constitute the “work of preparing coal” and thus they fall under the Mine Act, 30 U.S.C. § 802(h)(1), and second, because the Mine Safety and Health Administration promulgated regulations that preempt the Occupational Safety and Health Act, 29 U.S.C. §§ 651 to 678.
In order to understand how the operations at Penelec bring these two Acts into convergence, one must track the coal from the mine to the generator boilers. (See the parties’ stipulated Exhibit B entitled “Homer City Station Coal Flow Diagram” appended hereto.)
The “raw coal” used in the Penelec generating facility to produce power is delivered by conveyor belt from two adjacent mines. The conveyor belts move the coal from the adjacent mines to scales where it is weighed and sampled. The conveyor transports the coal to the coal processing station. At the station the coal is broken, crushed, sized, washed, cleaned, dried, and blended in order to make a “useable coal product” for the electric generating facility. At the time the citations were issued, the Iselin Preparation Company, a subsidiary of one of the two mining companies, operated the station. As the stipulated diagram denotes, MSHA had previously inspected and otherwise exercised jurisdiction over the Penelec processing station since 1977. However, it has never regulated the facilities used to move the processed coal leaving the station and destined for the generating facilities.
The present dispute concerns the head drives of the conveyor belts used to transport coal from the minehead scales to the processing station located at the entrance of Bin # 1 on the parties’ diagram. On January 7, 1988, an inspector from MSHA issued citations to Penelec for failing to place adequate guards around these head drives, as required under MSHA. 30 C.F.R. § 77.400(c). Penelec does not contest that it failed to guard the cited head drives or that MSHA satisfied its burden of proof with regard to the existence of the violations underlying the citations. It argues, however, that the MSHA inspector did not have the authority to issue the violations.
The Mine Act generally involves coal mining operations. See 30 U.S.C. § 801, et seq. Section 802(h)(1) provides that “structures, facilities, equipment, machines, tools or other property ... used in, or to be used in, or resulting from, ... the work of preparing coal” fall within the definition of “coal or other mine” and as such, are subject to the Mine Act’s jurisdiction under section 803. Section 802(i) defines the “work of preparing coal” as the “breaking, crushing, sizing, cleaning, washing, drying, mixing, storing, and loading of bituminous coal, lignite, or anthracite, and such other work of preparing such coal as is usually done by the operator of the coal mine.” Applying these provisions to the facts of this case, it is clear that the conveyor head drives 5A and 5B are structures used in the work of preparing coal and therefore come within the jurisdiction of the Mine Act.
Under the functional analysis we are to employ when giving the “broadest possible” scope to mine Act coverage, see generally, Marshall v. Stoudt’s Ferry Preparation Co., 602 F.2d 589, 592 (3d Cir.1979), cert. denied, 444 U.S. 1015, 100 S.Ct. 665, 62 L.Ed.2d 644 (1980), the delivery of coal from a mine to a processing station via a conveyor constitutes coal preparation “usually done by the operator of a coal mine.” 30 U.S.C. § 802(i). Thus the *1504plain language of section 802(h)(1) controls this case.
Our decision in Hanna v. Director, OWCP, 860 F.2d 88, 92-93 (3d Cir.1988), confirms that the head drives come under the Mine Act. Like the employee who loaded coal onto the barge in Hanna, the head drives serve a necessary function in the “work of preparing coal” by delivering raw coal to the Iselin station where it then undergoes further processing before it is ultimately transferred to the ultimate consumer, Penelec’s energy producing facility. This conclusion is also consistent with our decision in Stroh v. Director, OWCP, 810 F.2d 61 (3d Cir.1987), which held that the delivery of raw coal to a coal processing facility is an activity within the Mine Act, but not the delivery of completely processed coal to the ultimate consumer. Id. at 64.
Thus it is clear that Penelec’s head drives come under Mine Ac., jurisdiction, regardless of whether the facility receiving the coal for processing is also under Mine Act jurisdiction. We need only look to MSHA’s regulation of the conveyors leading to the coal cleaning facilities to reach the proper decision in this case.
OSHA generally involves safety in the generating plant. 29 U.S.C. § 651, et seq. OSHA regulations that would otherwise apply to the head drives, however, are preempted by MSHA regulations under § 4(b)(1) of OSHA. 29 U.S.C. § 653(b)(1). The OSHA preemption analysis in this case simply requires an application of our decision in Columbia Gas v. Marshall, 636 F.2d 913 (3d Cir.1980). Columbia Gas established a two-step inquiry into whether: (1) a regulation was promulgated by a state or federal agency other than OSHA; and (2) whether the regulation promulgated covers the specific “working conditions” at issue. Id. at 915-16. We defined “working conditions” as the “environmental area in which an employee customarily goes about his daily tasks.” Id. at 916. Once we are satisfied that a regulation was promulgated that covers the challenged working conditions, OSHA is preempted and the inquiry ends. We stated that the reviewing court need not look further than the face of the regulation: “[w]e therefore need not examine the substance of preemp-tory regulation; as long as it covers the identical working conditions, OSHA’s jurisdiction is preempted.” Id. at 918. Consequently, we need not examine the enforcement history of a particular regulation. OSHA § 4(b)(1) is satisfied by the very fact that a regulation with the requisite specificity is promulgated.
Applying Columbia Gas to the facts of. this case, it becomes clear that MSHA regulations preempt OSHA. The Mine Safety and Health Administration promulgated a safety regulation concerning conveyor head drives in 1971, and reauthorized this regulation through the period when the MSHA citations were issued to Penelec:
§ 77.400 Mechanical equipment guards.
(c) Guards at conveyor-drive, conveyor-head, and conveyor-tail pulleys shall extend a distance sufficient to prevent a person from reaching behind the guard and becoming caught between the belt and the pulley.
30 C.F.R. § 77.400(c). Section 77.400(c) prescribes a standard for the “environmental area,” that might pose a potential danger to Penelec workers. Under our jurisprudence, that is enough to answer the question of whether OSHA is preempted.
It may be argued that we should extend our Columbia Gas analysis beyond the two-step analysis and inquire into the “totality of circumstances” surrounding the enforcement history of a regulation. If, for example, competing agencies such as MSHA and OSHA are allowed to regulate a working condition, the'regulated party will not have adequate notice of what conduct constitutes a regulatory violation. While it may be unfair for a regulated party to be subject to the “whipsaw effects” of competing agency regulation, neither Columbia Gas nor the language of OSHA § 4(b)(1) can be read to authorize such an inquiry into the enforcement history of a regulation.
*1505In Columbia Gas we merely looked to whether the state agency promulgated a regulation covering the specific working conditions over which OSHA attempted to issue a citation. 636 F.2d at 916-17. The critical point was the specificity of the regulations, vis-a-vis the working conditions, rather than whether the regulations were consistently enforced. See U.S. Air, Inc. v. OSHRC, 689 F.2d 1191, 1192 (4th Cir.1982) (the “crux” of § 4(b)(1) preemption is the phrase “working conditions”).
Last, the plain language of § 4(b)(1) indicates that the enforcement history surrounding a regulation is not relevant to the issue of whether another agency preempts OSHA. Section 4(b)(1) provides, in pertinent part:
Nothing in this chapter shall apply to working conditions of employees with respect to which other Federal agencies ... exercise statutory authority to prescribe or enforce standards or regulations affecting occupational safety or health.
29 U.S.C. § 653(b)(1) (emphasis added). The operative language italicized above shows that the exercise of statutory authority by an agency triggers the preemption of OSHA. The statute does not require us to look beyond the exercise of statutory authority by the agency; no language refers to the quality or consistency of the agency’s exercise of statutory authority. It is not necessary to look beyond the plain terms of § 4(b)(1) to decide the dispute. As our Columbia Gas decision indicates, the preemption inquiry is satisfied once we determine that an agency has exercised its authority to prescribe a safety standard or regulation and that regulation covers the specific working conditions at issue.
Here, MSHA properly issued the two citations because, at the time they were issued, MSHA had regulations concerning the safety of conveyor head drives in force and those regulations addressed the precise working conditions at issue, i.e., the need for guards on conveyor head drives. Therefore, the two-step inquiry of Columbia Gas is satisfied and OSHA is preempted. The Secretary has satisfied her burden of showing that MSHA, rather than OSHA, is the proper agency regulating this part of Penelec’s facility.
After full consideration of the arguments of the parties upon rehearing, we uphold the citations and will affirm the Commission’s decision.
*1506EXHIBIT B
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