
    In the Matter of the Claim of Gerald Terwilliger, Appellant, v Green Fuel Economizer, Inc., et al., Respondents. Workers’ Compensation Board, Respondent.
   Appeal from a decision of the Workers’ Compensation Board, filed July 30,1982. Claimant contends that the board erred in apportioning his award between the industrial accident and the pre-existing condition and, further, that the board erred in finding his disability to be moderate. As to whether claimant’s entire disability is compensable, the crucial factor is whether claimant’s industrial accident acted on the pre-existing condition in such a manner as to cause disability which did not previously exist (Matter of Kuczkowski v Bethlehem Steel Corp., 90 AD2d 612, 613, affd 58 NY2d 946). Thus, where the pre-existing condition is dormant and not disabling, there will be no apportionment when a work-related accident activates the condition (Matter ofPodlish v McGraw Edison Co., 89 AD2d 712). Here, however, there is evidence in the record that claimant’s medical history showed low back problems when he began doing heavy work some two years before the accident. Although claimant’s attending physician, who began to treat claimant several years after the accident, testified that claimant’s pre-existing condition was asymptomatic prior to the accident, the resolution of the factual issue created by such conflicting medical evidence is exclusively for the board (see Matter of Parish v Rolex Plastics, 90 AD2d 625, mot for lv to app den 58 NY2d 604). Similarly, on the issue of the degree of claimant’s disability, there is conflicting medical testimony which was for the board to resolve. Since the board’s decision is supported by substantial evidence, it must be affirmed. Decision affirmed, without costs. Mahoney, P. J., Sweeney, Kane, Casey and Weiss, JJ., concur.  