Around 1986, defendant Royce W. Day Company, Inc. sold a used forklift truck that had been manufactured by defendant Raymond Corporation to third-party defendant, Yaun Company, Inc. The forklift could function as a conventional forklift truck or an order picker truck for elevated work. When used as an order picker the operator was outside the cab, standing on an operator's platform that was secured by means of a latching device to the elevating carriage of the forklift from which it could not fall. Once secured, the platform would be attached to whatever lifting surface the operator was intending to use, such as a pallet or skid. From this platform, the operator could drive the truck and raise and lower the platform and lifting surface through the use of remote controls.

On April 23, 1990, plaintiff William A. Smith (hereinafter plaintiff), an employee of Yaun, was using the forklift as an order picker; however, he was not utilizing the operator's platform manufactured by Raymond, but one Yaun designed and had manufactured. This platform resembled a pallet except that it had a solid wooden surface with two metal channels underneath it into which the forklift's forks were inserted. Instead of a permanent latching system, a metal chain was used to secure the platform to the forklift and prevent it from sliding off the forks. For some reason, the Yaun platform came off the forks, causing plaintiff to fall six feet to the floor and to sustain serious personal injuries.

Thereafter, plaintiff and his wife, derivatively, commenced this action asserting causes of action in strict products liability and negligence premised on the theory that the forklift was defectively designed in that it did not incorporate an interlock system that would have prevented the use of the forklift as an order picker when the operator's platform was not securely attached. Following discovery, defendants and Yaun moved for summary judgment dismissing the complaint. Supreme Court denied the motion, prompting this appeal.

A manufacturer who has designed and produced a safe product will not be liable if, after the product has left its possession and control, there is a significant modification which substantially alters the product provided the modification is the proximate cause of the injury (see, Ernest v. S.M.S. Eng'g, 223 A.D.2d 801, 802; Van Buskirk v. Migliorelli, 185 A.D.2d 587, 589, lv denied 80 N.Y.2d 761). Defendants maintain that the forklift was safe when used with the fully secured Raymond platform. Further, they contend that the proximate cause of plaintiff's accident was his use of the Yaun platform that apparently had not been adequately secured to the forklift.

This proof does not necessarily entitle defendants to summary judgment because a manufacturer may be held liable where its product is purposefully manufactured to permit its use without a safety device that is designed to be removable (see, O'Bara v Piekos, 161 A.D.2d 1118, 1119; LaPaglia v. Sears Roebuck Co., 143 A.D.2d 173, 177, lv dismissed and denied 74 N.Y.2d 624; Lopez v Precision Papers, 107 A.D.2d 667, 669, affd 67 N.Y.2d 871). Here, Raymond's documents unequivocally state that its platform with its permanent latching system is easily removable to enable rapid conversion between the forklift's functions. Moreover, as this incident illustrates, the forklift could be operated with a different platform that was not positively attached to the forklift. In view of this we believe it should be for the jury to determine the scope of the forklift's intended purposes and whether it was reasonably safe when placed in the stream of commerce (see, McAvoy v. Outboard Mar. Corp., 134 A.D.2d 245, 246). Accordingly, summary judgment was properly denied with respect to plaintiffs' causes of action based upon the design defect theory.

Although plaintiffs' failure to warn claim was not alleged in their complaint, but only in their bill of particulars, Supreme Court properly considered it given the fact that defendants challenged it in their moving papers (see, Alvord Swift v Muller Constr. Co., 46 N.Y.2d 276, 281; Stiber v. Cotrone, 153 A.D.2d 1006, 1007, lv denied 75 N.Y.2d 703; Ayala v. V O Press Co., 126 A.D.2d 229, 234). Inasmuch as there were no explicit warnings on the forklift that it was not to be used without the Raymond platform and as the proof is inconclusive as to whether Royce W. Day Company provided Yaun with an operator's manual containing such warning, we agree with Supreme Court that the adequacy of the warnings is a question of fact for the jury (see, Harrigan v Super Prods. Corp., 237 A.D.2d 882, 882-883). However, while Supreme Court's refusal to dismiss this cause of action was proper, it should have directed plaintiffs to serve an amended complaint encompassing this cause of action (see, Alvord Swift v. Muller Constr. Co., supra).

Cardona, P.J., Mercure, Casey and Carpinello, JJ., concur.

Ordered that the order is modified, on the law, without costs, by directing plaintiffs to serve an amended complaint in accordance herewith within 20 days of the date of this Court's decision, and, as so modified, affirmed.