delivered the opinion of the Court.
Last Term, this Court examined the relationship between federal and state authority in the nuclear energy field and concluded that States are precluded from regulating the *241safety aspects of nuclear energy. Pacific Gas & Electric Co. v. State Energy Resources Conservation & Development Comm’n, 461 U. S. 190, 211-213 (1983). This case requires us to determine whether a state-authorized award of punitive damages arising out of the escape of plutonium from a federally licensed nuclear facility is pre-empted either because it falls within that forbidden field or because it conflicts with some other aspect of the Atomic Energy Act.
Karen Silkwood was a laboratory analyst for Kerr-McGee1 at its Cimarron plant near Crescent, Okla. The plant fabricated plutonium fuel pins for use as reactor fuel in nuclear power plants. Accordingly, the plant was subject to licensing and regulation by the Nuclear Regulatory Commission (NRC) (then the Atomic Energy Commission) pursuant to the Atomic Energy Act, 42 U. S. C. §2011 et seq. (1976 ed. and Supp. V).2
During a 3-day period of November 1974, Silkwood was contaminated by plutonium from the Cimarron plant. On November 5, Silkwood was grinding and polishing plutonium samples, utilizing glove boxes designed for that purpose.3 In accordance with established procedures, she checked her hands for contamination when she withdrew them from the *242glove box. When some contamination was detected, a more extensive check was performed. A monitoring device revealed contamination on Silkwood’s left hand, right wrist, upper arm, neck, hair, and nostrils. She was immediately decontaminated, and at the end of her shift, the monitors detected no contamination. However, she was given urine and fecal kits and was instructed to collect samples in order to check for plutonium discharge.
The next day, Silkwood arrived at the plant and began doing paperwork in the laboratory. Upon leaving the laboratory, Silkwood monitored herself and again discovered surface contamination. Once again, she was decontaminated.
On the third day, November 7, Silkwood was monitored upon her arrival at the plant. High levels of contamination were detected. Four urine samples and one fecal sample submitted that morning were also highly contaminated.4 Suspecting that the contamination had spread to areas outside the plant, the company directed a decontamination squad to accompany Silkwood to her apartment. Silkwood’s roommate, who was also an employee at the plant, was awakened and monitored. She was also contaminated, although to a lesser degree than Silkwood. The squad then monitored the apartment, finding contamination in several rooms, with especially high levels in the bathroom, the kitchen, and Silk-wood’s bedroom.
The contamination level in Silkwood’s apartment was such that many of her personal belongings had to be destroyed. Silkwood herself was sent to the Los Alamos Scientific Laboratory to determine the extent of contamination in her vital body organs. She returned to work on November 13. That night, she was killed in an unrelated automobile accident. 667 F. 2d 908, 912 (CA10 1981).
*243Bill Silkwood, Karen’s father, brought the present diversity action in his capacity as administrator of her estate. The action was based on common-law tort principles under Oklahoma law and was designed to recover for the contamination injuries to Karen’s person and property. Kerr-McGee stipulated that the plutonium which caused the contamination came from its plant, and the jury expressly rejected Kerr-McGee’s allegation that Silkwood had intentionally removed the plutonium from the plant in an effort to embarrass the company. However, there were no other specific findings of fact with respect to the cause of the contamination.
During the course of the trial, evidence was presented which tended to show that Kerr-McGee did not always comply with NRC regulations. One Kerr-McGee witness conceded that the amount of plutonium which was unaccounted for during the period in question exceeded permissible limits.5 485 P. Supp. 566, 586 (WD Okla. 1979). An NRC official testified that he did not feel that Kerr-McGee was conforming its conduct to the “as low as reasonably achievable” standard.6 Ibid. There was also some evidence that the level of plutonium in Silkwood’s apartment may have exceeded that permitted in an unrestricted area such as a residence. Ibid.
*244However, there was also evidence that Kerr-McGee complied with most federal regulations. The NRC official testified that there were no serious personnel exposures at the plant and that Kerr-McGee did not exceed the regulatory requirements with respect to exposure levels that would result in significant health hazards. In addition, Kerr-McGee introduced the Commission’s report on the investigation of the Silkwood incident in which the Commission determined that Kerr-McGee’s only violation of regulations throughout the incident was its failure to maintain a record of the dates of two urine samples submitted by Silkwood.
The trial court determined that Kerr-McGee had not shown that the contamination occurred during the course of Silk-wood’s employment. Accordingly, the court precluded the jury from deciding whether the personal injury claim was covered by Oklahoma’s Workers’ Compensation Act, which provides the sole remedy for accidental personal injuries arising in the course of employment. Okla. Stat., Tit. 85, §§ 11, 12 (1981). Instead, the court submitted the elaims to the jury on alternative theories of strict liability and negligence.7
The court also instructed the jury with respect to punitive damages, explaining the standard by which Kerr-McGee’s conduct was to be evaluated in determining whether such damages should be awarded:
“[T]he jury may give damages for the sake of example and by way of punishment, if the jury finds the defendant or defendants have been guilty of oppression, fraud, or malice, actual or presumed. . . .
“Exemplary damages are not limited to cases where there is direct evidence of fraud, malice or gross negligence. They may be allowed when there is evidence *245of such recklessness and wanton disregard of another’s rights that malice and evil intent will be inferred. If a defendant is grossly and wantonly reckless in exposing others to dangers, the law holds him to have intended the natural consequences of his acts, and treats him as guilty of a willful wrong.” 485 F. Supp., at 603 (Appendix).
The jury returned a verdict in favor of Mr. Silkwood, finding actual damages of $505,000 ($500,000 for personal injuries and $5,000 for property damage) and punitive damages of $10 million. The trial court entered judgment against Kerr-McGee in that amount.
Kerr-McGee then moved for judgment n.o.v. or a new trial. In denying that motion, the court rejected Kerr-McGee’s contention that compliance with federal regulations precluded an award of punitive damages. The court noted that Kerr-McGee “had a duty under part 20 of Title 10 of the Code of Federal Regulations to maintain the release of radiation ‘as low as reasonably achievable.’ Compliance with this standard cannot be demonstrated merely through control of escaped plutonium to within any absolute amount.” Id., at 585. Therefore, the court concluded, it is not “inconsistent [with any congressional design] to impose punitive damages for the escape of plutonium caused by grossly negligent, reckless and willful conduct.” Ibid.
Kerr-McGee renewed its contentions with greater success before the Court of Appeals for the Tenth Circuit. That court, by decision of a split panel, affirmed in part and reversed in part. 667 F. 2d 908 (1981). The court first held that recovery for Silkwood’s personal injuries was controlled exclusively by Oklahoma’s workers’ compensation law. It thus reversed the $500,000 judgment for those injuries. The court then affirmed the property damage portion of the award, holding that the workers’ compensation law applied only to personal injuries and that Oklahoma law permitted an award under a theory of strict liability in the circumstances *246of this case. Finally, the court held that because of the federal statutes regulating the Kerr-McGee plant, “punitive damages may not be awarded in this case,” id., at 923.
In reaching its conclusion with respect to the punitive damages award, the Court of Appeals adopted a broad preemption analysis. It concluded that “any state action that competes substantially with the AEC (NRC) in its regulation of radiation hazards associated with plants handling nuclear material” was impermissible. Ibid. Because “[a] judicial award of exemplary damages under state law as punishment for bad practices or to deter future practices involving exposure to radiation is not less intrusive than direct legislative acts of the state,” the court determined that such awards were pre-empted by federal law. Ibid.
Mr. Silkwood appealed, seeking review of the Court of Appeals’ ruling with respect to the punitive damages award. We noted probable jurisdiction and postponed consideration of the jurisdictional issue until argument on the merits. 459 U. S. 1101 (1983).
I — < HH
We first address the jurisdictional issue. This Court is empowered to review the decision of a federal court of appeals “by appeal [if] a State statute [is] held by [the] court of appeals to be invalid as repugnant to the Constitution . . . .” 28 U. S. C. § 1254(2). Mr. Silkwood argues that because the Court of Appeals invalidated the punitive damages award on pre-emption grounds and because the basis for that award was a state statute, Okla. Stat., Tit. 23, § 9 (1981),8 the Court of Appeals necessarily held that the state statute was unconstitutional, at least as applied in this case. Accordingly, Mr. Silkwood contends, this case falls within the confines of 28 U. S. C. § 1254(2). We disagree.
*247In keeping with the policy that statutes authorizing appeals are to be strictly construed, Perry Education Assn. v. Perry Local Educators’ Assn., 460 U. S. 37, 43 (1983); Fornaris v. Ridge Tool Co., 400 U. S. 41, 42, n. 1 (1970), we have consistently distinguished between those cases in which a state statute is expressly struck down on constitutional grounds and those in which an exercise of authority under state law is invalidated "without reference to the state statute. The former come "within the scope of § 1254(2)’s jurisdictional grant. Malone v. White Motor Corp., 435 U. S. 497, 499 (1978); Dutton v. Evans, 400 U. S. 74, 76, n. 6 (1970). The latter do not. Perry Education Assn., supra, at 42; Hanson v. Denckla, 357 U. S. 235, 244 (1958); Wilson v. Cook, 327 U. S. 474, 482 (1946).9 See also County of Arlington v. United States, 669 F. 2d 925 (CA4), cert. denied, 459 U. S. 801 (1982); Minnesota v. Hoffman, 543 F. 2d 1198 (CA8 1976), cert. denied sub nom. Minnesota v. Alexander, 430 U. S. 977 (1977). The present case falls into the second category.
The Court of Appeals held that because of the pre-emptive effect of federal law, “punitive damages may not be awarded in this case.” 667 F. 2d, at 923. It did not purport to rule on the constitutionality of the Oklahoma punitive damages statute. The court did not mention the statute, and the parties did not contest or defend the constitutionality of the statute in their appellate briefs. While the award itself was struck down, the statute authorizing such awards was left untouched. Cf. Perry Education Assn., 460 U. S., at 42. Therefore, the present appeal is not "within our §1254(2) appellate jurisdiction.10
*248Nevertheless, the decision below is reviewable by writ of certiorari. Ibid. The issue addressed by the court below is important; it affects both the States’ traditional authority to provide tort remedies to their citizens and the Federal Government’s express desire to maintain exclusive regulatory authority over the safety aspects of nuclear power. Accordingly, treating the jurisdictional statement as a petition for certiorari, as we are authorized to do, 28 U. S. C. §2103, we grant the petition and reach the merits of the Court of Appeals’ ruling.
Ill
As we recently observed in Pacific Gas & Electric Co. v. State Energy Resources Conservation & Development Comm’n, 461 U. S. 190 (1983), state law can be pre-empted in either of two general ways. If Congress evidences an intent to occupy a given field, any state law falling within that field is pre-empted. Id., at 203-204; Fidelity Federal Savings & Loan Assn. v. De la Cuesta, 458 U. S. 141, 153 (1982); Rice v. Santa Fe Elevator Corp., 331 U. S. 218, 230 (1947). If Congress has not entirely displaced state regulation over the matter in question, state law is still pre-empted to the extent it actually conflicts with federal law, that is, when it is impossible to comply with both state and federal law, Florida Lime & Avocado Growers, Inc. v. Paul, 373 U. S. 132, 142-143 (1963), or where the state law stands as an obstacle to the accomplishment of the fall purposes and objectives of Congress, Hines v. Davidowitz, 312 U. S. 52, 67 (1941). Pacific Gas & Electric, supra, at 204. Kerr-McGee contends that the award in this case is invalid under either analysis. We consider each of these contentions in turn.
*249A
In Pacific Gas & Electric, an examination of the statutory scheme and legislative history of the Atomic Energy Act convinced us that “Congress . . . intended that the Federal Government should regulate the radiological safety aspects involved in the construction and operation of a nuclear plant.” 461 U. S., at 205. Thus, we concluded that “the Federal Government has occupied the entire field of nuclear safety concerns, except the limited powers expressly ceded to the States.” Id., at 212.
Kerr-McGee argues that our ruling in Pacific Gas & Electric is dispositive of the issue in this case. Noting that “regulation can be as effectively exerted through an award of damages as through some form of preventive relief,” San Diego Building Trades Council v. Garmon, 359 U. S. 236, 247 (1959), Kerr-McGee submits that because the state-authorized award of punitive damages in this case punishes and deters conduct related to radiation hazards, it falls within the prohibited field. However, a review of the same legislative history which prompted our holding in Pacific Gas & Electric, coupled with an examination of Congress’ actions with respect to other portions of the Atomic Energy Act, convinces us that the pre-empted field does not extend as far as Kerr-McGee would have it.
As we recounted in Pacific Gas & Electric, “[ujntil 1954 . . . the use, control, and ownership of nuclear technology remained a federal monopoly.” 461 U. S., at 206. In that year, Congress enacted legislation which provided for private involvement in the development of atomic energy. Atomic Energy Act of 1954, Act of Aug. 30, 1954, ch. 1073, 68 Stat. 919, as amended, 42 U. S. C. §2011 et seq. (1976 ed. and Supp. V). However, the Federal Government retained extensive control over the manner in which this development occurred. In particular, the Atomic Energy Commission was given “exclusive jurisdiction to license the transfer, *250delivery, receipt, acquisition, possession, and use of nuclear materials.” Pacific Gas & Electric, supra, at 207. See 42 U. S. C. §§ 2014(e), (z), (aa), 2061-2064, 2071-2078, 2091-2099, 2111-2114 (1976 ed. and Supp. V).
In 1959 Congress amended the Atomic Energy Act in order to “clarify the respective responsibilities ... of the States and the Commission with respect to the regulation of byproduct, source, and special nuclear materials.” 42 U. S. C. §2021(a)(1). See S. Rep. No. 870, 86th Cong., 1st Sess., 8-12 (1959). The Commission was authorized to turn some of its regulatory authority over to any State which would adopt a suitable regulatory program. However, the Commission was to retain exclusive regulatory authority over “the disposal of such . . . byproduct, source, or special nuclear material as the Commission determines . . . should, because of the hazards or potential hazards thereof, not be disposed of without a license from the Commission.” 42 U. S. C. § 2021(c)(4). The States were therefore still precluded from regulating the safety aspects of these hazardous materials.11
Congress’ decision to prohibit the States from regulating the safety aspects of nuclear development was premised on its belief that the Commission was more qualified to determine what type of safety standards should be enacted in this complex area. As Congress was informed by the AEC, the 1959 legislation provided for continued federal control over the more hazardous materials because “the technical safety considerations are of such complexity that it is not likely that any State would be prepared to deal with them during the foreseeable future.” H. R. Rep. No. 1125, 86th Cong., 1st Sess., 3 (1959). If there were nothing more, this concern over the States’ inability to formulate effective standards and *251the foreclosure of the States from conditioning the operation of nuclear plants on compliance with state-imposed safety standards arguably would disallow resort to state-law remedies by those suffering injuries from radiation in a nuclear plant. There is, however, ample evidence that Congress had no intention of forbidding the States to provide such remedies.
Indeed, there is no indication that Congress even seriously considered precluding the use of such remedies either when it enacted the Atomic Energy Act in 1954 or when it amended it in 1959. This silence takes on added significance in light' of Congress’ failure to provide any federal remedy for persons injured by such conduct. It is difficult to believe that Congress would, without comment, remove all means of judicial recourse for those injured by illegal conduct. See Construction Workers v. Laburnum Corp., 347 U. S. 656, 663-664 (1954).
More importantly, the only congressional discussion concerning the relationship between the Atomic Energy Act and state tort remedies indicates that Congress assumed that such remedies would be available. After the 1954 law was enacted, private companies contemplating entry into the nuclear industry expressed concern over potentially bankrupting state-law suits arising out of a nuclear incident. As a result, in 1957 Congress passed the Price-Anderson Act, an amendment to the Atomic Energy Act. Pub. L. 85-256, 71 Stat. 576. That Act established an indemnification scheme under which operators of licensed nuclear facilities could be required to obtain up to $60 million in private financial protection against such suits. The Government would then provide indemnification for the next $500 million of liability, and the resulting $560 million would be the limit of liability for any one nuclear incident.
Although the Price-Anderson Act does not apply to the present situation,12 the discussion preceding its enactment *252and subsequent amendment13 indicates that Congress assumed that persons injured by nuclear accidents were free to utilize existing state tort law remedies. The Joint Committee Report on the original version of the Price-Anderson Act explained the relationship between the Act and existing state tort law as follows:
“Since the rights of third parties who are injured are established by State law, there is no interference with the State law until there is a likelihood that the damages exceed the amount of financial responsibility required together with the amount of the indemnity. At that point the Federal interference is limited to the prohibition of making payments through the State courts and to prorating the proceeds available.” S. Rep. No. 296, 85th Cong., 1st Sess., 9 (1957).
See also H. R. Rep. No. 435, 85th Cong., 1st Sess., 9 (1957); S. Rep. No. 1605, 89th Cong., 2d Sess., 6 (1966).
Congress clearly began working on the Price-Anderson legislation with the assumption that in the absence of some subsequent legislative action, state tort law would apply.14 This was true even though Congress was fully aware of the *253Commission’s exclusive regulatory authority over safety matters. As the Joint Committee explained in 1965:
“The Price-Anderson Act also contained provisions to improve the AEC’s procedures for regulating reactor licensees .... This manifested the continuing concern of the Joint Committee and Congress with the necessity for assuring the effectiveness of the national regulatory program for protecting the health and safety of employees and the public against atomic energy hazards. The inclusion of these provisions . . . also reflected the intimate relationship which existed between Congress’ concern for prevention of reactor accidents and the indemnity provisions of the Price-Anderson legislation.” S. Rep. No. 650, 89th Cong., 1st Sess., 4-5 (1965).
When it enacted the Price-Anderson Act, Congress was well aware of the need for effective national safety regulation. In fact, it intended to encourage such regulation. But, at the same time, “the right of the State courts to establish the liability of the persons involved in the normal way [was] maintained.” S. Rep. No. 296, supra, at 22.
The belief that the NRC’s exclusive authority to set safety standards did not foreclose the use of state tort remedies was reaffirmed, when the Price-Anderson Act was amended in 1966. The 1966 amendment was designed to respond to concerns about the adequacy of state-law remedies. See, e. g., S. Rep. No. 650, supra, at 13. It provided that in the event of an “extraordinary nuclear occurrence,”15 licensees could be required to waive any issue of fault, any charitable or govern*254mental immunity defense, and any statute of limitations defense of less than 10 years. 42 U. S. C. §2210(n)(l). Again, however, the importance of the legislation for present purposes is not so much in its substance, as in the assumptions on which it was based.
Describing the effect of the 1966 amendment, the Joint Committee stated:
“By requiring potential defendants to agree to waive defenses the defendants’ rights are restricted; concomitantly, to this extent, the rights of plaintiffs are enlarged. Just as the rights of persons who are injured are established by State law, the rights of defendants against whom liability is asserted are fixed by State law. What this subsection does is to authorize the [NRC] to require that defendants covered by financial protection and indemnity give up some of the rights they might otherwise assert.” S. Rep. No. 1605, 89th Cong., 2d Sess., 26 (1966).
Similarly, when the Committee outlined the rights of those injured in nuclear incidents which were not extraordinary nuclear occurrences, its reference point was again state law. “Absent ... a determination [that the incident is an “extraordinary nuclear occurrence”], a claimant would have exactly the same rights that he has today under existing law — including, perhaps, benefit of a rule of strict liability if applicable State law so provides.” Id., at 12. Indeed, the entire discussion surrounding the 1966 amendment was premised on the assumption that state remedies were available notwithstanding the NRC’s exclusive regulatory authority. For example, the Committee rejected a suggestion that it adopt a federal tort to replace existing state remedies, noting that such displacement of state remedies would engender great opposition. Hearings before the Joint Committee on Atomic Energy on Proposed Amendments to Price-Anderson Act Relating to Waiver of Defenses, 89th Cong., 2d Sess. ,31, 75 (1966); S. Rep. No. 1605, supra, at 6-9. If other provi*255sions of the Atomic Energy Act already precluded the States from providing remedies to its citizens, there would have been no need for such concerns. Other comments made throughout the discussion were similarly based on the assumption that state remedies were available.16
Kerr-McGee focuses on the differences between compensatory and punitive damages awards and asserts that, at most, Congress intended to allow the former. This argument, however, is misdirected because our inquiry is not whether Congress expressly allowed punitive damages awards. Punitive damages have long been a part of traditional state tort law. As we noted above, Congress assumed that traditional principles of state tort law would apply with full force unless they were expressly supplanted. Thus, it is Kerr-McGee’s burden to show that Congress intended to preclude such awards. See Electrical Workers v. Foust, 442 U. S. 42, 53 (1979) (Blackmun, J., concurring in result). Yet, the company is unable to point to anything in the legislative history or in the regulations that indicates that punitive damages were not to be allowed. To the contrary, the regulations issued implementing the insurance provisions of the Price-Anderson Act themselves contemplate that punitive damages might be awarded under state law.17
*256In sum, it is clear that in enacting and amending the Price-Anderson Act, Congress assumed that state-law remedies, in whatever form they might take, were available to those injured by nuclear incidents. This was so even though it was well aware of the NRC’s exclusive authority to regulate safety matters. No doubt there is tension between the conclusion that safety regulation is the exclusive concern of the federal law and the conclusion that a State may nevertheless award damages based on its own law of liability. But as we understand what was done over the years in the legislation concerning nuclear energy, Congress intended to stand by both concepts and to tolerate whatever tension there was between them. We can do no less. It may be that the award of damages based on the state law of negligence or strict liability is regulatory in the sense that a nuclear plant will be threatened with damages liability if it does not conform to state standards, but that regulatory consequence was something that Congress was quite willing to accept.
We do not suggest that there could never be an instance in which the federal law would pre-empt the recovery of damages based on state law. But insofar as damages for radiation injuries are concerned, pre-emption should not be judged on the basis that the Federal Government has so completely occupied the field of safety that state remedies are foreclosed but on whether there is an irreconcilable conflict between the federal and state standards or whether the imposition of a state standard in a damages action would frustrate the objectives of the federal law. We perceive no such conflict or frustration in the circumstances of this case.
*257B
The United States, as amicus curiae, contends that the award of punitive damages in this case is pre-empted because it conflicts with the federal remedial scheme, noting that the NRC is authorized to impose civil penalties on licensees when federal standards have been violated. 42 U. S. C.. §2282 (1976 ed. and Supp. V). However, the award of punitive damages in the present case does not conflict with that scheme. Paying both federal fines and state-imposed punitive damages for the same incident would not appear to be physically impossible. Nor does exposure to punitive damages frustrate any purpose of the federal remedial scheme.
Kerr-McGee contends that the award is pre-empted because it frustrates Congress’ express desire “to encourage widespread participation in the development and utilization of atomic energy for peaceful purposes.” 42 U. S. C. § 2013(d). In Pacific Gas & Electric, we observed that “[t]here is little doubt that a primary purpose of the Atomic Energy Act was, and continues to be, the promotion of nuclear power.” 461 U. S., at 221. However, we also observed that “the promotion of nuclear power is not to be accomplished ‘at all costs.’” Id., at 222. Indeed, the provision cited by Kerr-McGee goes on to state that atomic energy should be developed and utilized only to the extent it is consistent “with the health and safety of the public.” 42 U. S. C. § 2013(d). Congress therefore disclaimed any interest in promoting the development and utilization of atomic energy by means that fail to provide adequate remedies for those who are injured by exposure to hazardous nuclear materials. Thus, the award of punitive damages in this case does not hinder the accomplishment of the purpose stated in § 2013(d).
We also reject Kerr-McGee’s submission that the punitive damages award in this case conflicts with Congress’ express intent to preclude dual regulation of radiation hazards. See S. Rep. No. 870, 86th Cong., 1st Sess., 8 (1959). As we *258explained in Part A, Congress did not believe that it was inconsistent to vest the NRC with exclusive regulatory authority over the safety aspects of nuclear development while at the same time allowing plaintiffs like Mr. Silkwood to recover for injuries caused by nuclear hazards. We are not authorized to second-guess that conclusion.18
>
We conclude that the award of punitive damages in this case is not pre-empted by federal law. On remand Kerr-McGee is free to reassert any claims it made before the Court of Appeals which were not addressed by that court or by this opinion, including its contention that the jury’s findings with respect to punitive damages were not supported by sufficient evidence and its argument that the amount of the punitive damages award was excessive. The judgment of the Court of Appeals with respect to punitive damages is therefore reversed, and the case is remanded to that court for proceedings consistent with this opinion.
It is so ordered.
Silkwood was employed by Kerr-McGee Nuclear Corp., a subsidiary of Kerr-McGee Corp. The jury found that the former was the “mere instrumentality” of the latter. We therefore refer to both as Kerr-McGee.
Under 42 U. S. C. §2073, the Commission is authorized to issue licenses to those who handle special nuclear materials like the plutonium processed in Kerr-McGee’s plant. Section 2201(b) empowers the Commission to set standards and issue instructions to govern the possession and use of such materials. On April 2, 1970, Kerr-McGee obtained a license to receive and possess special nuclear materials at its Cimarron plant. It closed the plant in 1975.
A glove box is a supposedly impervious box surrounding the plutonium-processing equipment which has glove holes permitting the operator to work on the equipment or the plutonium from outside the box.
At trial, the parties stipulated that the urine samples had been spiked with insoluble plutonium, i. e., plutonium which cannot be excreted from the body. However, there was no evidence as to who placed the plutonium in the vials.
After allowing for hold-up (plutonium which remains in the equipment after a very thorough cleanout), the inventory difference (opening less closing) for the 1972-1976 period was 4.4 kilograms. This represented 0.522% of the 842 kilograms received by Kerr-McGee during that period. The NRC permits an inventory difference of 0.5%.
Federal regulations require that “persons engaged in activities under licenses issued by the Nuclear Regulatory Commission . . . make every reasonable effort to maintain radiation exposures, and releases of radioactive materials in effluents to unrestricted areas, as low as is reasonably achievable.” 10 CFR §20.1(c) (1983). In 1974, the regulation required reasonable efforts to maintain exposures and releases “as far below the limits specified [in other portions of the regulations] as practicable.” The difference in the terminology is not significant. 40 Fed. Reg. 33029 (1975).
In an effort to avoid a new trial in the event that the Court of Appeals disagreed with its ruling on the applicability of strict-liability principles, the court instructed the jury to answer a special interrogatory as to whether Kerr-McGee negligently allowed the plutonium to escape from its plant. The jury answered in the affirmative.
The Oklahoma statute authorizes an award of punitive damages “[i]n any action for the breach of an obligation not arising from contract, where the defendant has been guilty of oppression, fraud or malice, actual or presumed.”
Wilson and Denckla involve appeals from state-court judgments under 28 U. S. C. § 1257 and its predecessor. However, such cases are relevant to the present issue because of “the history of . . . close relationship between” § 1254(2) and § 1257. Calero-Toledo v. Pearson Yacht Leasing Co., 416 U. S. 663, 675-677, n. 11 (1974).
Mr. Silkwood’srelianee on California v. Grace Brethren Church, 457 U. S. 393 (1982), is misplaced. Grace Brethren involved a direct appeal under 28 *248U. S. C. § 1252, a statute which we have construed more broadly because of Congress’ clear intent to create an “exception to the policy of minimizing the mandatory docket of this Court.” Id., at 405. See also McLucas v. DeChamplain, 421 U. S. 21, 31 (1975).
At the time this suit was filed, Oklahoma had not entered into an agreement with the Commission under §2021. Even if it had, Kerr-McGee would have still been subject to exclusive NRC safety regulation because it was licensed to possess special nuclear material in a quantity sufficient to form a critical mass. See 42 U. S. C. § 2021(b)(4) (1976 ed. and Supp. V).
Under the Act, the NRC is given discretion whether to require plants licensed under §2073 to maintain financial protection. 42 U. S. C. § 2210(a). Government indemnification is available only to those required *252to maintain financial protection, § 2210(c), and certain others not relevant here, §2014(t), and the liability limitation applies only to those who are indemnified. § 2210(e). The NRC did not require plutonium processing plants to maintain financial protection until 1977, 42 Fed. Reg. 46 (1977).
The 1957 version of the Price-Anderson Act was designed to expire in 1967. It was extended in 1965, Pub. L. 89-210, 79 Stat. 855, and again in 1975, Pub. L. 94-197, 89 Stat. 1111. In addition, several substantive changes were made through the years, most notably in 1966. Pub. L. 89-645, 80 Stat. 891.
In sustaining the Price-Anderson Act against a constitutional challenge, we echoed that assumption, noting that before the Act was enacted the only right possessed by those injured in a nuclear incident “was to utilize their existing common-law and state-law remedies to vindicate any particular harm visited on them from whatever source.” Duke Power Co. v. Carolina Environmental Study Group, Inc., 438 U. S. 59, 88, 89, n. 32 (1978).
An “extraordinary nuclear occurrence” is “any event causing a discharge or dispersal of source, special nuclear, or byproduct material from its intended place of confinement in amounts offsite, or causing radiation levels offsite, which the Commission determines to be substantial, and which the Commission determines has resulted or will probably result in substantial damages to persons offsite or property offsite.” 42 U. S. C. § 2014(j). The Commission’s criteria for defining an extraordinary nuclear occurrence are located at 10 CFR §§ 140.81-140.85 (1983).
Atomic Energy Commission General Counsel Hennessey testified that “[i]t would appear eminently reasonable to avoid disturbing ordinary tort law remedies with respect to damage claims where the circumstances are not substantially different from those encountered in many activities of life which cause damage to persons and property.” Hearings before the Joint Committee on Atomic Energy on Proposed Amendments to Price-Anderson Act Relating to Waiver of Defenses, 89th Cong., 2d Sess., 35 (1966).
See also id., at 41 (“the amendments would not actually change the structure of the tort laws of the various states. The legal principles of state law would remain unchanged, but certain of the issues and defenses . . . would be affected”).
Following the 1966 amendment, the Commission published a form for nuclear energy liability policies and indemnity agreements. After reciting the waivers being made by the licensee in the event of an extraordinary nuclear occurrence, the form contains the following provision: “The waiv*256ers set forth... above do not apply to ... [a]ny claim for punitive or exemplary damages . . . .” 10 CFR § 140.91, Appendix A, ¶2(c), p. 801 (1983).
Had the Commission thought that punitive damages awards were precluded by earlier legislation, as Kerr-McGee suggests, there would have been no need to state that the waivers did not apply to such awards. Since the waivers do not apply at all to the present situation, the clear implication is that punitive damages are available, if state law so provides.
The Government cites no evidence to support its claim that the present award conflicts with the NRC’s desire to avoid penalties which put “a licensee out of business ... or adversely affec[t] a licensee’s ability to safely conduct licensed activities.” 47 Fed. Reg. 9991 (1982). Thus, we need not decide whether an award could be so large as to conflict with that policy. Of course, Kerr-McGee is free to challenge the propriety of the amount of the award on remand. See text infra, this page.