The plaintiffs appeal from a judgment resulting from a jury verdict in favor of the defendant, Westinghouse Electric Corporation (Westinghouse). They allege two errors by the trial judge: (1) his refusal to instruct the jury that electricity is a highly dangerous force and that those who deal with it are held to a high degree of care, and (2) his refusal to instruct the jury that, had Westinghouse given a warning of the hazards of using its product, the warning would have been followed. There was no error.

At the time of the accident which brought about the filing of this action, the plaintiffs were long-time employees of Boston Edison. They were conducting a test on electrical lines at an Edison substation that had been isolated from the main transmission line because of problems with its primary line. The plaintiffs’ testing was to ensure that all was repaired before the substation was returned to service. They were injured when the dispatcher who had sent them to the substation negligently ordered another employee to close a switch. As a result, a short circuit developed at the substation, and there was an electrical explosion, injuring the plaintiffs. The explosion occurred in a test device designed, manufactured, and sold by Westinghouse. Neither plaintiff had on protective gear at the time of the explosion.

*9931. Electricity as a highly dangerous force. There was no error in the judge’s refusal to instruct the jury that Westinghouse had an elevated duty of care. The plaintiffs’ arguments fail to take into account that their claim against Westinghouse was for breach of warranty and not for negligence. In breach of warranty cases, the “inquiry focuses on product characteristics rather than on the defendant’s conduct.” Back v. Wickes Corp., 375 Mass. 633, 642 (1978). The plaintiffs’ request to have the judge instruct on a higher degree of care owed would have mistakenly directed the jury to focus on Westinghouse’s conduct. Rather, the jury was required to consider “the gravity of the danger posed by the challenged design, the likelihood that such danger would occur, the mechanical feasibility of a safer alternative design, the financial cost of an improved design, and the adverse consequences to the product and to the consumer that would result from an alternative design.” Back v. Wickes Corp., supra, quoting from Barker v. Lull Engr. Co., 20 Cal. 3d 413, 431 (1978). The judge properly instructed the jury on these considerations.

2. Warning being followed. Although this court has decided that “[a]n adequate warning is by definition one that would in the ordinary course have come to the user’s attention” and prevented the accident, Wolfe v. Ford Motor Co., 6 Mass. App. Ct. 346, 352 (1978) (where it was likely a warning would have prevented the accident), we think reliance solely on that principle is misplaced here. The plaintiffs claim that the trial judge improperly instructed the jury about warnings being heeded. They argue that the instruction as given left the jury to speculate about the impact of a warning, rather than permitting an inference that a warning would have been followed.2 Harlow v. Chin, 405 Mass. 697, 702 (1989). On the evidence presented, however, the instruction given was sufficient. There was persuasive evidence that the plaintiffs would not have followed an adequate warning. See Knowlton v. Deseret Med., Inc., 930 F.2d 116, 123 (1st Cir. 1991). Moreover, “a manufacturer has no duty to warn a plaintiff who is fully aware of the risks posed by the product.” See Barbosa v. Hopper Feeds, Inc., 404 Mass. 610, 615 (1989). The plaintiffs were well aware of the possible dangers of working with the Westinghouse test device and electricity in general. They were trained to wear protective clothing and not to place certain equipment on the lines until they tested dead. The jury could well infer that there would only be a remote “possibility rather than a probability” that a warning from Westinghouse would have made the plaintiffs behave any differently while using the test device. Sweeting v. *994Cairns & Brother, Inc., ante 27, 29 (1992), quoting from Swartz v. General Motors Corp., 375 Mass. 628, 632 (1978). Additionally, “where the danger presented by a given product is obvious, no duty to warn [exists] because a warning will not reduce the likelihood of injury.” Bavuso v. Caterpillar Industrial, Inc., 408 Mass. 694, 699 (1990), quoting from Colter v. Barber-Greene Co., 403 Mass. 50, 59 (1988).

Judgment affirmed.