【国外标准】 Standard Specification for Asbestos Lap (Withdrawn 2022)

This specification establishes the properties of asbestos lap, a felted asbestos product, having a specified minimum mass % of asbestos fiber. Asbestos laps covered here are classified in two styles (Style 1 and 2) according to physical construction, five grades (Commercial, Underwriters', A, AA, AAA, and AAAA) according to mass percentage of asbestos content, and three types (Types II, IV, and VI) according to magnetic rating. Laps shall be made from a uniformly carded or otherwise felted blend of fibers. Specimens shall be sampled, prepared, tested, and conform accordingly to specified chemical composition (asbestos content), electromagnetic (magnetic rating), and dimensional (mass per unit length, and width) property requirements.1.1 This specification covers asbestos lap, a felted asbestos product, having a minimum of 75 mass % of asbestos fiber.1.2 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.1.3 Warning—Breathing of asbestos dust is hazardous. Asbestos and asbestos products present demonstrated health risks for users and for those with whom they come into contact. In addition to other precautions, when working with asbestos-cement products, minimize the dust that results. For information on the safe use of chrysoltile asbestos, refer to “Safe Use of Chrysotile Asbestos: A Manual on Preventive and Control Measures.” 21.4 The following safety hazards caveat pertains only to the test methods, Section 12, described in this specification: This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific safety hazard, see 1.3.1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.