1.1 This guide covers information on selection of insulation materials, systems design, application methods, protective coverings, guarantees, inspection, testing, and maintenance of thermal insulation primarily for industrial applications in a temperature range of –320 to 1200°F (–195.5 to 648.8°C). 1.2 This guide is intended to provide practical guidelines, by applying acceptable current practice while indicating the basic principles by which new materials can be assessed and adapted for use under widely differing conditions. Design engineers, the general contractors, the fabricators, and the insulation contractors will find this guide helpful. 1.3 Although some insulation system designs can serve as fire protection, this guide does not address the criteria specific to that need. API 521 Guide for Pressure-Relieving and Depressuring Systems is recommended as a reference for fire protection. This guide will however address the fire properties of insulation materials. 1.4 This guide is not intended for commercial, architectural, acoustical, marine, vehicle transport, or military use. 1.5 This guide does not address insulation system design for refractory linings or cold boxes whereby these are typically package units and of a proprietary insulation design. 1.6 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.7 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.