U.S. Plywood-Champion Paper, Inc., appeals from a jury verdict of $27,000.00 in a product liability case tried under Iowa law. In September 1969, Sven Sterner purchased a can of Weldwood Contact Cement, an all-purpose adhesive manufactured by the defendant for retail sale. While he was using the adhesive in the kitchen of his mobile home it ignited, causing a flash fire which injured him. In his complaint, the plaintiff pleaded alternatively (1) strict liability for a defective product, and (2) negligence in failing to provide adequate warning on proper and safe use of the product. By special interrogatory, the jury rejected the plaintiff’s first theory but found in his favor on the theory of negligence. Judgment was entered on the verdict and this appeal followed.
The defendant alleges several grounds of error on appeal: (1) that the district court erred in denying defendant’s motions for a directed verdict and judgment n. o. v. since (a) the warnings provided on the label were sufficient as a matter of law, and (b) the plaintiff was guilty of contributory negligence as a matter of law; (2) that the trial court erred in the admission of evidence; (3) that several instructions given by the court were erroneous; and (4) that the findings of the jury as embodied in their answers to the special interrogatories were inconsistent. We find no error and affirm the judgment of the district court.
The label on the can purchased by Sterner bore on. its face the admonition:
DANGER! Extremely flammable. Vapor harmful!
On the rear it warned:
DANGER: EXTREMELY FLAMMABLE MIXTURE. DO NOT USE NEAR FIRE OR FLAME,
in larger letters, and in smaller print:
DANGER! BEFORE USING extinguish all flames and pilot lights. During application and until vapors are gone, keep away from heat, sparks or flame. Avoid using spark producing electrical equipment such as switches, appliances, etc. Keep container closed when not in use.
and:
VAPOR HARMFUL. AVOID PROLONGED OR REPEATED BREATHING OF VAPOR. USE ONLY IN WELL-VENTILATED AREAS.
The plaintiff testified that he read the warnings and had extinguished all the pilot lights in the kitchen. He testified that he was using an electric fan for ventilation and that he did not disconnect the refrigerator. According to the testimony of plaintiff’s expert witness, Weldwood adhesive has a flash point roughly equivalent to that of gasoline. He described it as extremely flammable. An employee of the defendant testified that Weldwood could be safely used in a mobile home, but that it would be necessary to extinguish all pilot lights and disconnect all electrical appliances, even an electric wall clock if one were present. Whether the label sufficiently warned a user of these precautions, and whether the plaintiff acted as a reasonable person under the circumstances existing, we deem as fact questions for the jury. As we observed in Buffington v. *1354Amchem Products, Inc., 489 F.2d 1053, 1055 (8th Cir. 1974):
Under Iowa law, a manufacturer who undertakes to produce and sell to the general public a product whose use could possibly result in harm must provide sufficient instruction and give adequate warning. The instructions should give reasonable notice and specific direction as to proper use and all attendant risks which are foreseeable to a manufacturer who possesses superior knowledge so that the ordinary, user may be fully informed. Lakatosh v. Diamond Alkali Co., 208 N.W.2d 910 (Iowa 1973); West v. Broderick & Bas-com Rope Co., 197 N.W.2d 202 (Iowa 1972). See also Comment, The Manufacturer’s Duty to Warn of Dangers Involved in Use of a Product, 1967 Wash.U.L.Q. 206.1
The defendant’s challenge to the evidence concerns two sets of exhibits offered into evidence by the plaintiff. The first consisted of several advertisements, not seen by the plaintiff before his injury, puffing the utility of Weld-wood as an all-purpose household adhesive. The second (Exhibits 19, 20 and 21) was comprised of three Weldwood labels, each subsequent to and different from that which appeared on the can purchased by the plaintiff and each of which contained a more emphatic warning of the product’s dangerous properties. It is fundamental that the trial court has broad discretion over the admissibility of evidence. See General Ins. Co. of America v. Hercules Constr. Co., 385 F.2d 13, 24 (8th Cir. 1967). We find no error in the admission of these exhibits.
Subsequent alteration in the warnings given concerning the proper use of a product are, just as evidence of post-accident modifications in the product itself, inadmissible as an implied admission of negligence. Evidence of such changes are, however, admissible for some purposes such as demonstration of knowledge of dangerous properties prior to the accident or the availability of better design or the feasibility of a more adequate warning of the risk involved. See Lolie v. Ohio Brass Co., 502 F.2d 741, 744 (7th Cir. 1974); Hoppe v. Midwest Conveyor Co., 485 F.2d 1196, 1202 (8th Cir. 1973); Bowman v. General Motors Corp., 64 F.R.D. 62, 70 (E.D.Pa.1974); Incollingo v. Ewing, 444 Pa. 263, 282 A.2d 206 (1971); Love v. Wolf, 249 Cal. App.2d 822, 58 Cal.Rptr. 42, 48-49 (1967). Exhibit 19 was a label in use prior to September 1969 and was relevant to the issue of the plaintiff’s pre-accident knowledge. Exhibits 20 and 21 were indicative of the feasibility of providing more explicit, detailed and understandable warnings. We find no error in their admission. The advertisements were, we believe, also relevant since they were probative on the plaintiff’s claim, ultimately rejected by the jury, that the defendant’s adhesive was unfit for its intended uses. They were, of course, evidence of its intended uses.
We have considered the instructions given by the trial court on the issues of contributory negligence and proximate cause and the alleged inconsistency of the verdict, and we find no prejudicial error. The jury’s rejection of plaintiff’s theory of strict liability as to a defective product was not inconsistent with a finding of negligence based on the inadequacy of the warning. The *1355jury could have rationally concluded the product was fit for its intended use so long as the defendant properly warned its users of the dangers involved.
Judgment affirmed.
. In Lakatosh v. Diamond Alkali Co., 208 N.W.2d 910, 913 (Iowa 1973), the Iowa Supreme Court offered the following comments on a supplier’s duty to warn:
A duty to warn depends on superior knowledge and is said to exist when one may reasonably foresee danger of injury or damage to one less knowledgeable unless adequate warning of danger is given. It is this reasonable foreseeability which triggers the obligation to warn, which must be determined by the circumstances of each case.
Whether notice or warning should have been given under particular circumstances, like most questions bearing on negligence, is ordinarily for the jury. It is only in exceptional cases that it may be determined as a matter of law.