【国外标准】 Standard Guide for Selection of Cleaning Techniques for Masonry, Concrete, and Stucco Surfaces

4.1 Cleaning of masonry, concrete, and stucco surfaces is undertaken for a variety of reasons including aesthetic improvement, removal of contaminants, maintenance, and surface preparation. This guide provides for selecting, testing, and evaluating cleaning techniques for removal of soiling and staining.4.2 Cleaning systems may adversely affect both building materials being cleaned as well as other materials, mechanical, electrical, and other building systems, and building exterior, interior, and site features.4.3 In some situations, it may be prudent to spot clean or to not clean.4.4 It should be noted that, in some cases, cleaning may be inconsistent with the goals of historic preservation.1.1 This guide covers procedures for the selection and assessment of cleaning techniques for removing soiling and staining from masonry, concrete, and stucco surfaces. Removal of paints, coatings, and graffiti may require measures beyond the scope of this guide. New construction is excluded from the scope of this guide.1.2 This guide does not purport to address the causes of soiling or staining or to propose remedies for recurring soiling or staining.1.3 Where work on surfaces of artistic, architectural, cultural, or historic significance is being considered, guidance from specialists should be sought.1.4 This guide does not purport to address removal and replacement of prior repairs, repair of damaged surfaces, or other irregularities that contribute to the uneven or discolored appearance of masonry, concrete, and stucco surfaces.1.5 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.1.6 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.7 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.