Grosse, C.j. Swanson and Winsor, JJ. Pro Tem., concur.
The Celotex Corporation*fn1 and Raymark Industries, Inc. (collectively referred to as appellants) appeal a jury verdict and award to Lewis Koker and Roberta Koker (Koker) for damages arising from Mr.
Koker's exposure to asbestos-containing products manufactured by appellants.
Lewis W. Koker worked as a pipefitter at the Todd and Lockheed Shipyards in Seattle from 1969 to 1971, and again from 1974 through 1986. While working at the shipyards he was exposed to asbestos-containing insulation products manufactured by the appellants. Koker claimed that as a result of this exposure to asbestos-containing materials he developed pleural thickening or pleural plaques in his lungs. He has asbestos fibers in his lungs and, according to testimony at trial, these fibers may cause him to develop asbestosis, mesothelioma, and/or lung cancer in the future. He testified he was often short of breath and troubled by a recurring cough.
Koker testified he knew he had been exposed to asbestos and the exposure was not good. However, he also testified that it was not until Lockheed sent most of its workers to Harborview Medical Center for tests in 1985 that he truly feared the results of his exposure. A physician first diagnosed Koker's pleural plaques in 1988. This case was filed on August 9, 1985.*fn2 Koker testified that as a result of his condition he has a reasonable fear of contracting cancer or other asbestos-related diseases. His wife testified regarding her perception of his fear and her opinion of the condition of his health.
At trial the appellants claimed the statute of limitations barred Koker's claims because he knew or should have known enough to file an action earlier than he did. The trial court held that the determination of the date of accrual of Koker's claim was a question for the jury. The jury determined, by special verdict, that Koker's claims, under theories of negligence and strict liability, were not
barred. The jury also determined that the appellants supplied products which were "not reasonably safe" and which were a proximate cause of the damage to Koker. Further, the jury found the appellants negligent and that this negligence was a proximate cause of the damage to Koker. The total amount of damages awarded by the jury was $107,500. This appeal followed.
Applicability of the 1981 Tort Reform Act
Central to the appellants' position in this appeal is the question of whether the provisions of the 1981 tort reform act (hereinafter Act) apply to this case. The Act, by its terms, applies "to all claims arising on or after July 26, 1981." See RCW 4.22.920. The appellants contend Koker's claim is a products liability claim arising after July 26, 1981, and thus governed by the Act. Koker argues his claim arose before the Act, but did not accrue until a later date, thus contending the pre-Act law should apply.
Of interest in the analysis is the legislative history regarding the use of the term "arising." As originally drafted, the 1981 tort reform act provided that the statute would apply to those claims " accruing " after July 26, 1981. However, as finally passed by the Legislature, the word "accruing" was changed to "arising." See Report of Standing Committee, Senate Journal, 47th Legislature (1981), at 613; see RCW 4.22.920.
 In construing a statute, the court's paramount duty is to ascertain and give expression to the intent of the Legislature. Service Employees Int'l Union, Local 6 v. Superintendent of Pub. Instruction, 104 Wash. 2d 344, 348, 705 P.2d 776 (1985); Hama Hama Co. v. Shorelines Hearings Bd., 85 Wash. 2d 441, 445, 536 P.2d 157 (1975). To determine the intent of the Legislature, the court first looks to the language of the statute. Condit v. Lewis Refrigeration Co., 101 Wash. 2d 106, 110, 676 P.2d 466 (1984). The Legislature is presumed to know the meaning of the words used in writing its enactments. State v. Zornes, 78 Wash. 2d 9, 19, 475 P.2d 109 (1970). An elementary rule of statutory construction is
that where the Legislature uses certain statutory language in one instance, and different language in another, there is a difference in legislative intent. See United Parcel Serv., Inc. v. Department of Rev., 102 Wash. 2d 355, 362, 687 P.2d 186 (1984). This rule, although usually cited in the context of the use of different language within the same statute and therefore not fully on point in this case, is instructive by analogy. Although the terms "accruing" and "arising" were not used in different places within RCW 4.22.920, before final passage of the (amendatory) Act, the Legislature specifically changed the word from "accruing" to "arising" when enacting the applicability section. Laws of 1981, ch. 27, § 15. As shown below, the terms arising and accruing are not synonymous.
 A court must give words in a statute their plain and ordinary meaning unless a contrary intent appears. In re Estate of Little, 106 Wash. 2d 269, 283, 721 P.2d 950 (1986). "Arising" or "arising out of" is ordinarily understood to mean "originating from", "having its origin in", "growing out of", or "flowing from." Avemco Ins. Co. v. Mock, 44 Wash. App. 327, 329, 721 P.2d 34 (1986). As shown in Martin v. Patent Scaffolding, 37 Wash. App. 37, 42-43, 678 P.2d 362, review denied, 101 Wash. 2d 1021 (1984), arising (or arose) and accruing are definitely not the same. In Martin, a products liability case, the case "arose" when the plaintiff fell from the scaffolding (pre-Act), but did not "accrue" for purposes of applying the statute of limitations until the plaintiff discovered or should have discovered all the elements of the cause of action (postenactment).
Further, there has been an interpretation of the same "arising" language which is contained in RCW 4.22.925*fn3 as well as RCW 4.22.920. In Mina v. Boise Cascade Corp., 37 Wash. App. 445, 450-51, 681 P.2d 880 (1984) (automobile accident on I-82 outside Ellensburg), aff'd, 104 Wash. 2d 696,
710 P.2d 184 (1985), the court determined that any confusion as to the statutory claim was eliminated by the amendment. The court held that because the cause of action (accident) in the Mina case "arose" prior to the effective date of the Act, the jury in that case was properly instructed on comparative negligence (pre-Act standard) rather than contributory negligence (postenactment standard). The case was not filed until after the effective date of the Act.
The Mina case follows those Washington cases holding that a claim arises when the injury producing event takes place, not when the claim is filed. See, e.g., Zamora v. Mobil Oil Corp., 104 Wash. 2d 199, 214-15, 704 P.2d 584 (1985); Thompson v. Rockford Mach. Tool Co., 49 Wash. App. 482, 483, 744 P.2d 357 (1987), review denied, 110 Wash. 2d 1007 (1988). See also Lenhardt v. Ford Motor Co., 102 Wash. 2d 208, 209, 683 P.2d 1097, 40 A.L.R.4th 609, (1984); Lockwood v. AC&S, Inc., 44 Wash. App. 330, 346-47, 722 P.2d 826 (1986), aff'd, 109 Wash. 2d 235, 744 P.2d 605 (1987). Here, the exposure to the asbestos was in the late 1960's, the 1970's, and 1980's.*fn4 Because the harm here results from exposure (continuous in nature), it appears that substantially all of the events which can be termed "injury producing" occurred prior to the adoption of the Act. The case was sent to the jury under instructions based on pre-Act law. Because the claim arose prior to the Act, we hold the trial court was correct in applying, and instructing the jury on, the case law and statutes in effect prior to the adoption of the Act. The contention of the appellants that the Act applies necessarily fails.
Directed Verdict and Statute of Limitations
The appellants contend the trial court erred in refusing to grant a motion for a directed verdict on the fear of cancer claim. The appellants argue that Koker's claim was barred by the statute of limitations and that there was insufficient evidence to support Koker's claims.
 As previously discussed, contrary to the appellants' contention, the Act does not apply in this case. The law in regard to statute of limitation defenses for claims arising prior to the Act is governed by the "discovery rule." A statute of limitation begins to run when a cause of action has accrued. See Martin v. Patent Scaffolding, 37 Wash. App. at 42-43 (interpreting former RCW 4.16.010). Here, the applicable statute is RCW 4.16.080(2). The discovery rule applies to product liability cases. The claim does not accrue until the claimant discovers, or reasonably should have discovered, all of the essential elements of the possible cause of action. Ohler v. Tacoma Gen. Hosp., 92 Wash. 2d 507, 598 P.2d 1358 (1979). As explained in White v. Johns-Manville Corp., 103 Wash. 2d 344, 348, 693 P.2d 687 (1985):
In an ordinary personal injury action, the general rule is that a cause of action "accrues" at the time the act or omission occurs. In certain torts, however, injured parties do not, or cannot, know they have been injured; in these cases, a cause of action accrues at the time the plaintiff knew or should have known all of the essential elements of the cause of action. The rule of law postponing the accrual of the cause of action is known as the "discovery rule".
 A cause of action in a negligence case accrues when a plaintiff discovers or reasonably should have discovered the essential elements of negligence, i.e., duty, breach, causation and damages. See Ohler, 92 Wash. 2d at 511. A products liability cause of action accrues when the plaintiff discovers or reasonably should have discovered that (1) he or she suffers physical harm from a product which has a defective condition making it unreasonably dangerous; (2) the ...