—Orders of the Supreme Court, New York County (Karla Moskowitz, J.), both entered on or about July 1, 1994, which granted defendants’ motion for summary judgment to the extent of granting them partial summary judgment dismissing plaintiffs’ respective causes of action for negligence, reversed, to the extent appealed from, on the law, without costs, and the causes of action for ordinary negligence reinstated.
In these two personal injury actions, consolidated for trial, the injured plaintiffs assert causes of action for ordinary negligence and medical malpractice arising from the poisoning of intravenous fluid, administered while each was unconscious and recovering from orthopedic surgery. The surgeries were performed on the morning of April 21,1989 in operating rooms 4 and 5, located on the 10th floor of defendant Lenox Hill Hospital. In both cases, Pavulon, a neuromuscular blocking agent, was injected into intravenous bags, causing the patients to suffer respiratory paralysis. Both were treated with muscle relaxant reversal agents and revived.
Upon investigation, it was discovered that one intravenous bag from each operation bore a needle puncture mark and that there was a high concentration of Pavulon in the solution. Discarded vials of the anesthetic and wrappings from intravenous bags were found under a shelf in a storage room, located just off the operating rooms on the 10th floor. This room was not locked, and detectives with the New York City Police Department concluded that this is where the tampering probably took place.
It is plaintiffs’ theory that defendant hospital was negligent in failing to secure the room in which the Pavulon was stored. Defendants, in seeking dismissal of the complaints (CPLR 3211 [a] [7]; 3212), argue that, because the person who intentionally injected the potentially lethal amount of Pavulon into the intravenous solution bags has never been identified, the temporary paralysis experienced by the injured plaintiffs is attributable to the act of an intervening agent. Therefore, they contend, even presuming that the hospital was negligent in failing to lock the storeroom or otherwise secure the anesthetic, any injury is attributable to a criminal and unforeseeable superseding act that breaks any causal connection with the purported negligence.
Defendants contend that reinstatement of the respective claims for ordinary negligence is only appropriate "upon a *185showing, not made in the court below nor here * * * that a person or persons responsible for committing these acts was unauthorized to be on the 10th floor or in the Department of Anesthesia.” Defendants’ brief also states that the poisoning agent, Pavulon, was stored "in the Department of Anesthesia, itself * * * accessible only to authorized hospital personnel.” Thus, defendants do not dispute the duty of a hospital to safeguard the welfare of its patients, even "from harm inflicted by third persons, measured by the capacity of the patient to provide for his or her own safety” (Clinton v City of New York, 140 AD2d 404, 405 [liability imposed on hospital for stabbing by another patient] [citing Killeen v State of New York, 66 NY2d 850; Mochen v State of New York, 57 AD2d 719], lv denied 73 NY2d 703). Nor do defendants deny the responsibility of a hospital to protect against unauthorized use of drugs under its control. They simply contend that limiting the availability of anesthetic drugs to authorized hospital personnel was adequate to fulfill that duty.
Defendants ask this Court to conclude that it was the act of "one or more demented individuals” or a "criminal assailant or assailants” that led to the adulteration of the solution in the intravenous bags. However, it would be more accurate to state that there is an absence of proof with respect to who administered the Pavulon, when it was introduced into the intravenous bags, how it was acquired or where the tampering took place, except that the evidence suggests it was on the 10th floor of the hospital. Defendants therefore seek to deny the injured plaintiffs recovery on their ordinary negligence theory because the circumstances under which the drug came to be introduced into the intravenous solution and the person or persons responsible cannot be ascertained.
It is well settled that where the facts permit conflicting inferences to be drawn, summary judgment must be denied (Dollas v Grace & Co., 225 AD2d 319). Therefore, while it is plausible that the criminal act of an intervening agent caused the harm for which recovery is sought, adopting defendants’ theory requires the resolution of factual inferences in favor of defendants, which is improper on a motion for summary judgment seeking the dismissal of a cause of action (Harris v City of New York, 147 AD2d 186, 191).
Questions of fact are raised by the testimony of plaintiffs’ experts that the hospital’s failure to secure anesthetic drugs constitutes a deviation from accepted practice. But even ignoring this issue, dismissal of the causes of action for ordinary negligence asserted against the hospital is unwarranted. The *186circumstances of this incident afford sufficient basis for an inference of negligence under the doctrine of res ipsa loquitur: it involves injury which would not have occurred in the absence of negligence in safeguarding a dangerous substance, admittedly under the hospital’s exclusive control (Richardson, Evidence § 93 [Prince 10th ed]). In view of the concession by the hospital that access to the Pavulon was restricted to its agents, plaintiffs have established a prima facie case of negligence (Fisch, New York Evidence § 1137, at 654 [2d ed]), and summary judgment dismissing their claims for ordinary negligence must be denied. Concur—Rosenberger, J. P., Ellerin and Rubin, JJ.; Tom, J., dissents in a memorandum; Kupferman, J., concurs in the dissent in a separate memorandum, all as follows: