The plaintiff John Good is serving a life sentence without the possibility of parole, imposed by a judge of the Superior Court after his conviction of murder in the first degree. He filed this action in the Superior Court for the county of Middlesex, invoking G. L. c. 12, §§ 11H-11J (1992 ed.), claiming that the defendant commissioner and the Department of Correction (department) denied him periodic review of his inmate classification as required by 103 Code Mass. Regs. § 420.00, and also claiming violation of art. 26 of the Massachusetts Declaration of Rights, the prohibition against cruel or unusual punishments.

The trial judge denied Good’s motion to be returned to a correctional facility in the Commonwealth and granted summary judgment for the commissioner on both claims raised by Good. Good appealed. The Appeals Court affirmed the grant of summary judgment in favor of the commissioner on Good’s claim under art. 26 but reversed as to his claim of denial of periodic review and remanded the case for further proceedings on that claim alone. Good v. Commissioner of Correction, 34 Mass. App. Ct. 73, 77-78 (1993). We granted the plaintiff’s request for further appellate review. We agree with the Appeals Court that the trial judge improperly granted summary judgment in favor of the commissioner on Good’s claim of denial of review of his inmate classification. Additionally, however, we conclude that the trial judge improperly granted summary judgment in favor of the commissioner on Good’s art. 26 claim.

We recite the essential facts of this case. Good was convicted of murder in the first degree in 1988 and began serving his sentence at the Massachusetts Correctional Institution, Cedar Junction. He was transferred in 1989 to the custody of the Federal Bureau of Prisons (FBOP). After his transfer, he was held at the United States penitentiaries *331(USP) at Lewisburg, Pennsylvania, and Leavenworth, Kansas. Good then was temporarily returned to Cedar Junction in May, 1990, so that he could assist in preparing the appeal of his murder conviction. It was during this temporary stay at Cedar Junction that Good filed this action, pro se. In June, 1990, prior to the hearing on his request for an injunction to prohibit his return to the custody of the FBOP, Good was returned to the FBOP. He currently is serving his sentence at USP, Marion, Illinois.

1. Review of his inmate classification. Good’s first claim was that, under the department’s regulations, 103 Code Mass. Regs. § 420.00 (1992), and the due process provisions of the Massachusetts Constitution, he is entitled to review of his inmate classification even though he is not in the physical custody of the department. The commissioner argues that Good has no right to such review and, even if he does, he has been afforded the required review. A judge of the Superior Court ruled that only inmates in the physical custody of the department (inmates not serving sentences in out-of-State or Federal facilities) are entitled to review under the department’s regulations.1

We conclude that the department’s own regulations require meaningful and periodic review of Good’s classification. Thus, we conclude that it is unnecessary to address the assertion by Good that the due process provisions of the Massa*332chusetts Constitution require this review.2 See Michaud v. Sheriff of Essex County, 390 Mass. 523, 526 (1983), citing Beeler v. Downey, 387 Mass. 609, 613 (1982).

The department’s regulations regarding classification are applicable “to all inmates at state, county and federal correctional institutions who are serving a sentence imposed by the state of Massachusetts.” 103 Code Mass. Regs. § 420.04 (1992). There is no dispute that Good is serving a sentence imposed by the Commonwealth. Thus, the classification regulations apply to him. The regulations further provide that “[e]ach inmate’s case shall be reviewed at least once every six months subsequent to initial classification.” 103 Code Mass. Regs. § 420.09 (1) (1992). The language of the regulations is unambiguous that inmates in the custody of the FBOP are entitled to classification reviews every six months. See Ladetto v. Commissioner of Correction, 373 Mass. 859, 860 (1977). The department is bound by the mandate of its own regulations, Royce v. Commissioner of Correction, 390 Mass. 425, 427 (1983), and therefore must review Good’s classification in accordance with the procedure described in 103 Code Mass. Regs. § 420.08 (6) (a) - (h) adapted as necessary to accommodate Good’s placement in an out-of-State, high-level security facility.

Summary judgment may be granted only when the moving party demonstrates that there is no genuine issue as to any material fact and that the movant is entitled to judgment as a matter of law. Mass. R. Civ. P. 56 (c), 365 Mass. 824 *333(1974). Flesner v. Technical Communications Corp., 410 Mass. 805, 808-809 (1991). The commissioner contends that the department has afforded Good meaningful and periodic review of his classification. Good contends that it has not performed these reviews and that, if reviews are being conducted, he is not being notified or given an opportunity to make a presentation. Thus there exists a dispute of material fact whether the department has reviewed and continues to review Good’s classification in accordance with its own regulations. The granting of summary judgment was improper and so we reverse the judgment of the trial court. There must be further proceedings on this issue.

2. Good’s claim of violation of art. 26 of the Declaration of Rights. Good’s other claim is that his confinement at USP Marion subjects him to cruel or unusual punishment in violation of art. 26 of the Massachusetts Declaration of Rights. More specifically, Good, who has a history of bladder cancer, claims that the drinking water at Marion contains carcinogenic substances which unreasonably increase the risk that Good will suffer a recurrence of bladder cancer. The commissioner counters that since Good is in Federal custody, any claim arising out of the conditions of confinement at Marion lies against Federal authorities, not against the commissioner. The judge agreed with the commissioner and granted his motion for summary judgment.

In support of his opposition to the commissioner’s motion for summary judgment, Good submitted a memorandum, affidavits and other exhibits. Viewed in the light most favorable to Good, these documents tended to show that Good was successfully treated during the 1970’s for bladder cancer; that the drinking water supply at Marion contains substances which increase greatly a person’s risk of cancer, including bladder cancer; that Good’s only source of drinking water is this contaminated water; that Good is more likely to get bladder cancer from consuming the water than someone who does not have a history of bladder cancer; and that, if Good suffers a recurrence of bladder cancer, he is more *334likely to die than someone who does not have a history of bladder cancer.3

Good is not seeking money damages for an alleged injury caused by his consumption of the water at Marion, nor is he seeking an order to compel the prison officials at Marion to remedy the drinking water contamination problem. Rather, Good’s complaint sought an order prohibiting the department from transferring him to Marion where he would be exposed to the contaminated water.

The defendant does not address the merits of Good’s claim, but instead asserts that the commissioner is not the proper party defendant since Good has been transferred to the physical custody of the FBOP. This contention is misplaced. The plaintiff is seeking to return to a correctional facility in the Commonwealth; he is not seeking an injunction ordering the FBOP to remedy the drinking water problem. The department maintains jurisdiction over inmates transferred to Federal custody. Ladetto v. Commissioner of Correction, 373 Mass. 859, 859-860 (1977). See G. L. c. 124, §§ 1 (f), (g) (1992 ed.); G. L. c. 127, § 97A (1992 ed.).4 Since the commissioner has the ability to prevent harm to Good, by, for example, transferring him to another facility with safe drinking water, but has failed to do so, Good should have been allowed to maintain his suit against the commissioner. Cf. Inmates of Suffolk County Jail v. Eisenstadt, 494 F.2d 1196, 1199 (1st Cir. 1974) (commissioner is subject to court order where he has “major statutory responsibilities bearing precisely on the issues raised in the inmates’ suit”). The judge erred in granting summary judgment for *335the commissioner on the ground that the commissioner was not a proper party defendant.

The judge did not address the merits of Good’s art. 26 claim in granting the commissioner’s motion for summary judgment. We take this opportunity to offer guidance on the validity of that claim because the issue is likely to arise on remand.

Article 26 of the Declaration of Rights prohibits the infliction of cruel or unusual punishments. This court has read art. 26 to be at least as broad as the Eighth Amendment to the Federal Constitution. Michaud v. Sheriff of Essex County, 390 Mass. 523, 534 (1983). Article 26 bars punishments which are found to be cruel or unusual in light of contemporary standards of decency which mark the progress of society. Id. at 533. Libby v. Commissioner of Correction, 385 Mass. 421, 435 (1982). In divining contemporary standards of decency, we may look to State statutes and regulations, which reflect the public attitude as to what those standards are. Michaud, supra at 527, 529-530.5

In establishing the Executive Office of Environmental Affairs, the Legislature noted that “providing safe water to drink and clean air to breathe is a basic mandate.” G. L. c. 21A, § 2 (2), inserted by St. 1974, c. 806. To fulfil this mandate, the Department of Environmental Protection has promulgated detailed regulations setting minimum quality standards for drinking water. See 310 Code Mass. Regs. § 22.00 (1992). Recognizing that prison inmates are entitled to safe drinking water, the Department of Public Health requires that correctional facilities in the Commonwealth must provide at all times safe and sanitary drinking water. 105 Code Mass. Regs. § 451.125 (1992).

*336Although we do not rule that these provisions are constitutionally required, we do conclude that they reflect the public attitude that contemporary society’s standards of decency include the availability of safe drinking water. This standard applies to all citizens of the Commonwealth, including inmates under the control of the department. Consumption of contaminated water poses a health risk to which not even prison inmates should be subject. Cf. Helling v. McKinney, 113 S. Ct. 2475, 2480 (1993).

Thus, if Good has no option, as a result of his confinement at Marion, but to drink water which poses a substantial risk of serious harm to his health and the department has knowledge of the situation and ignores it, then these circumstances arguably would violate Good’s rights under art. 26. See Miga v. Holyoke, 398 Mass. 343, 349-350 (1986); Baptiste v. Sheriff of Bristol County, 35 Mass. App. Ct. 119, 122 (1993). See also Helling, supra at 2480-2481, citing Youngberg v. Romeo, 457 U.S. 307, 315-316 (1982); Jackson v. Arizona, 885 F.2d 639, 641 (9th Cir. 1989).6 An inmate need not wait until he suffers actual harm before he can assert a cause of action under art. 26. See Libby, supra at 434. Rather, a claim is made out if there is a substantial risk that the inmate will suffer serious harm as a result of the conditions of his confinement. See Helling, supra at 2480.

If, on remand, Good satisfies the judge that his art. 26 rights have been, and continue to be, violated,7 the trial *337judge will be faced with the task of fashioning an appropriate remedy. Good suggests that the remedy should be an injunction ordering the commissioner to return Good to the Commonwealth. Based on the record before us, however, we cannot say that such an injunction would be the most appropriate remedy.8

The commissioner has broad discretion to transfer inmates from one facility to another facility operated by the department, or to a facility operated by another State or the Federal government. See Nelson v. Commissioner of Correction, 390 Mass. 379, 397 (1983); Jackson v. Commissioner of Correction, 388 Mass. 700, 703 (1983). On the other hand, the judiciary will not stay its hand should the commissioner fail to meet his obligations under the Constitution of the Commonwealth. Michaud, supra at 534.

The order of the trial judge granting summary judgment in favor of the defendant is vacated and the judgment is reversed. The case is remanded to the trial court for further proceedings in accordance with this opinion.

So ordered.

(concurring, with whom Nolan, J., joins). I agree that the plaintiff is entitled to review of his classification under the department’s regulations. The plaintiff argues status as if it were a constitutional attack on the use of transfers.*3381 The only issue being remanded is status, not the constitutionality of-the transfer statute.

I also write separately on the issue of water standards. The court’s opinion assumes that Massachusetts water standards differ from Federal standards with respect to the alleged contaminants and that the Massachusetts standards are higher. There is no basis for such an assumption on this record. The plaintiff makes no such allegation. Indeed, the complaint does not allege any violation of either Federal or Massachusetts water standards. The exhibits attached to the plaintiff’s opposition to the commissioner’s motion to dismiss or for summary judgment focus on whether the water at USP, Marion, violates Federal standards. Because the question whether the water at USP, Marion, meets Federal standards is being litigated in Illinois, see Wyler v. Environmental Protection Agency, et al., U.S. Dist. Ct. for So. Dist., Ill., No. (1994), I would expressly limit the remand hearing to the question whether Massachusetts water standards differ from Federal water standards with respect to the alleged contaminants. If the standards are essentially the same, then the Superior Court judge should await the outcome of the litigation in Illinois.2 Illinois is the appropriate venue for the *339determination whether the water at USP, Marion, meets Federal standards.

Last, I would follow the test annunciated in Helling v. McKinney, 113 S. Ct. 2475 (1993).3 In Helling, supra at 2481, the United States Supreme Court held that “[a prisoner] could state a cause of action under the Eighth Amendment by alleging that [prison officials] have, with deliberate indifference, exposed him to levels of [environmental tobacco smoke] that pose an unreasonable risk of serious damage to his future health.” The Supreme Court then remanded the case “to the District Court to provide an opportunity for [the prisoner] to prove his allegations, which will require him to prove both the subjective [deliberate indifference] and the objective [unreasonable risk of serious damage to his future health] elements necessary to prove an Eighth Amendment violation. The District Court will have the usual authority to control the order of proof, and if there is a failure of proof on the first element that it chooses to consider, it would not be an abuse of discretion to give judgment for [the prison officials] without taking further evidence.” Id. at 2481-2482. The Supreme Court went on to note that, “with respect to the objective factor, determining whether [the prisoner’s] conditions of confinement violate the Eighth Amendment requires more than a scientific and statistical inquiry into the seriousness of the potential harm and the likelihood that such injury to health will actually be caused by exposure to [environmental tobacco smoke]. It also requires a court to assess whether society considers the risk that the prisoner complains of to be so grave that it violates contemporary standards of decency to expose anyone unwillingly to such a risk. In other words, the prisoner must show that the risk of which he complains is not one that today’s society chooses to tolerate.” (Emphasis in original.) Id. at 2482. If it is determined that the Massachusetts water standards are essentially the same as the Federal standards with respect to the alleged contaminants and that the water at USP, Marion, satisfies the Fed*340eral standards, then summary judgment should enter for the commissioner because such a determination would establish that the risk of which the plaintiff complains is one that “today’s society chooses to tolerate."