FOREWORD A. This Standard represents the judgment of Underwriters Laboratories Inc.@ as to the basic requirements for the construction and performance of the products to be investigated under this category. These requirements are based upon sound engineering principles@ research@ records of tests and field experience@ and an appreciation of the problems of manufacture@ installation@ and use derived from consultation with and information obtained from manufacturers@ users@ inspection authorities@ and others having specialized experience. They are subject to revision as further experience and investigation may show is necessary or desirable. B. The observance of the requirements of this Standard by a manufacturer is one of the conditions of the continued Listing of the manufacturer's product. Underwriters Laboratories Inc.@ however@ assumes no responsibility for the effect of such observance or nonobservance by the manufacturer upon the relations between the manufacturer and any other party or parties arising out of the sale or use of the product or otherwise. C. A product which complies with these requirements will not necessarily be eligible for Listing if@ when examined and tested@ it is found to have other features which impair the result contemplated by these requirements. D. A product employing materials or having forms of construction differing from those detailed in these requirements may be examined and tested according to the intent of the requirements and@ if found to be substantially equivalent@ may be Listed. E. Many tests required by the Standards of Underwriters Laboratories Inc.@ are inherently hazardous. Underwriters Laboratories Inc.@ neither assumes nor accepts any responsibility for any injury or damage that may occur during or as the result of tests@ wherever performed@ whether performed in whole or in part by the manufacturer or the Laboratories@ and whether or not any equipment@ facility@ or personnel for or in connection with the test is furnished by the manufacturer or the Laboratories.