The issue presented by this appeal is whether a motion for summary judgment pursuant to Civ. R. 56 should have been granted to appellants on the grounds that the appellants had violated no duty in the manufacturing and selling of a crawler-type tractor without roll-over protection. For the reasons which follow, this court holds that the grant of summary judgment was improper, for there was sufficient evidence presented to raise- a question of fact as to whether the design of the tractor without roll-over protection was in a defective condition.
In recent years, this court has had several opportunities to define the duties of a manufacturer relative to product design. In the seminal case of Temple v. Wean United, Inc. (1977), 50 Ohio St. 2d 317 [4.O.O.3d 466], this *234court adopted Section 402A of the Restatement of Torts 2d, thus providing a cause of action in strict liability for injury from a product in Ohio. This court recently elaborated on the basic principles set forth in Temple in Leichtamer v. American Motors Corp. (1981), 67 Ohio St. 2d 456 [21 O.O.3d 285], and Knitz v. Minster Machine Co. (1982), 69 Ohio St. 2d 460 [23 O.O.3d 403].
In Knitz, this court set forth the proper legal standard to be applied in cases alleging a design defect in a manufactured product which causes injury:
“A product design is in a defective condition if it is more dangerous than an ordinary consumer would expect when used in an intended or reasonably foreseeable manner or if the benefits of the challenged design do not outweigh the risk inherent in such design. * * *”
The test set forth in Knitz does not impose a dual requirement that an injured plaintiff prove that a product design is both in a defective condition and unreasonably dangerous. As this court aptly noted in Knitz, at page 464, fn. 2, “* * * [t]o require an injured plaintiff to prove both that a product contained a defect and that the defect rendered the product ‘unreasonably dangerous’ would place a greater requirement upon him than required by * * * [this court’s] initial formulation of strict liability in tort announced in Lonzrick v. Republic Steel Corp., supra [(1966), 6 Ohio St. 2d 227 (35 O.O. 2d 404)]. * * *”
Rather, Knitz sets forth a single, two-pronged test for determining whether a product design is in a defective condition. Under the first prong, commonly referred to as the consumer expectation standard, a defendant will be subject to liability if the plaintiff proves that the product design is in a defective condition because the product fails to perform as safely as an ordinary consumer would expect when used in an intended or reasonably foreseeable manner.
Under the second prong, a defendant will be subject to liability if the plaintiff proves, by using relevant criteria, that the product design is in a defective condition because the benefits of the challenged design do not outweigh the risks inherent in such design. This standard is often referred to as the risk-benefit standard.
In Knitz, at page 466, this court listed three criteria that it deemed relevant in weighing the merits of a particular design: “* * * the likelihood that the product design will cause injury, the gravity of the danger posed, and the mechanical and economic feasibility of an improved design.” The listing of these three factors was not meant to be, nor should it be construed to be, exclusive and exhaustive.
For, as this court stated in Knitz, at 465, fn. 2, the focus of our inquiry in determining whether a particular product design is in a defective condition under the risk-benefit standard is on “* * * the nature of [the] ‘defect’ * * *.”1 In focusing on the product design, basic justice requires that all par*235ties have the right to have attention directed to all relevant factors for consideration in determining whether the particular product is in a defective condition. Other factors relevant to the evaluation of the defectiveness of the product design may include the relative costs of producing, distributing and selling an alternative design and new or additional harms that may result from an alternative design.2
As this court refrains from setting forth an exclusive test of relevant factors, it likewise refrains from according any priority to these factors. The appropriate factors, and the weight allocated to each factor, will vary with the facts of each case.3
Applying these standards to the instant case, while remaining mindful that this case involves the grant of summary judgment and that the evidence must thus be construed most favorably for appellees herein, this court concludes that appellees have made out a genuine issue of fact as to whether appellants’ crawler tractor was defective in design. This court concurs with the conclusion of the court of appeals that there were sufficient allegations in the pleadings and depositions to establish a genuine issue of material fact as to whether the benefits of the challenged design outweighed the risks inherent in such design.
The deposition of appellee indicates that it was dangerous not to have a roll bar on the crawler tractor and that several models had such equipment. John A. Prosek, an engineer and former employee of International Harvester, who was involved with the design of roll-over protection, stated in his deposition that the company was aware that errors in judgment while using the equipment could result in roll-over accidents, that federal regulations requiring roll-over protection were being formulated at the time of manufacture of the crawler tractor, that it would have cost approximately $1,000 per *236tractor to install roll-over protection, and that a marketing decision was made to offer the protection as an option.4
Appellants also argue that even if this court holds that the trial court improperly granted summary judgment on the issue of the alleged defective condition of the product design, this court should nevertheless reinstate summary judgment in their favor by ruling that appellee voluntarily assumed the risk of his injury. In this regard, the court of appeals stated as follows: “[i]t is not necessary to consider the issues of contributory negligence and assumption of the risk, since the trial court did not grant summary judgment on these grounds and the issues were not raised on appeal.”
This court concurs in this assessment made by the court of appeals. Inasmuch as the issue of assumption of the risk was not properly before the court of appeals, it likewise is not properly before this court.
For the foregoing reasons, the judgment of the court of appeals is affirmed.
Judgment affirmed.
Celebrezze, C.J., Sweeney, Locher, C. Brown and J. P. Cele-BREZZE, JJ., concur.
Holmes, J., dissents.