Occupational Diseases: General Principles. Chapter 52, which discusses the general principles associated with occupational diseases, will be revised and updated. All states now provide general compensation coverage for such diseases. Jurisdictions usually define the term to include any disease arising out of exposure to harmful conditions of the employment, when those conditions are present in a peculiar or increased degree by comparison with employment generally. Thus, even a disease which is rare and which is due to the claimant's individual allergy or weakness combining with employment conditions will usually be held to be an occupational disease if the increased exposure occasioned by employment in fact brought on the disease. As is the case with any workers' compensation claim, the burden of proof in establishing occupational disease claims lies with the claimant. It is insufficient to show that the disease or condition might have been associated with the conditions of the workplace; specific proof must be offered. In the case of a hearing loss claim, for example, anecdotal testimony as to noise levels and conditions generally will be insufficient to establish a claim. That some hearing loss over time has been suffered is not enough.

For example, in one recent New York case, Matter of Zahm v. National Fuel, 72 A.D.3d 1311, 898 N.Y.S.2d 367 (3d Dept. 2010), a claimant worked for the employer in numerous capacities for 31 years, first as a data entry clerk, and then in various customer-related positions until she retired in July 2005. A pre-employment hearing examination conducted in 1974 revealed that claimant had a measurable loss of hearing at that time. In August 2007, the worker filed a workers' compensation claim contending that she had sustained an occupational hearing loss due to long-term noise exposure from being on the telephone for years. The employer did not dispute that claimant had suffered a hearing loss; it argued rather that the record failed to establish both that claimant was exposed to injurious noise during the course of her employment and that her documented hearing loss was causally related to her employment. The appellate court agreed. The court acknowledged that while it was clear that claimant spent part of her working day on the telephone with customers who sometimes were either irate or had difficulty hearing, claimant's description of the actual noise level, which was not measured, was simply too vague and imprecise to establish that it was in fact injurious. Even accepting that claimant was exposed to injurious noise while working for the employer, the court nonetheless agreed that claimant failed to demonstrate a causal connection between her hearing loss and her employment [see Ch. 52, § 52.05[5] n48].