"The IICRC Standard for Professional Water Damage Restoration (IICRC S500) is a procedural standard. It is based on reliable restoration principles, research and practical experience. In addition, there has been extensive consultation and information obtained from numerous sources. These sources include, but are not necessarily limited to, the scientific community, the international, national and regional trade associations serving the professional disaster restoration industry, chemical formulators and equipment manufacturers, cleaning and restoration training schools, restoration service companies, the insurance industry, allied trades persons and others with specialized experience. It is subject to further revision as developments occur in technology, testing and processing procedures. The Fourth Edition of the IICRC S500 Standard and Reference Guide has been completely updated and rewritten with the best information and knowledge of the time. Additional Chapters and Sections have been added to the S500 that have not been included previously. These areas include: Building and Material Science, Psychrometry by Definition, Psychrometry and the Science of Drying, Limitations Complexities Complications and Conflicts, Structural Restoration, HVAC, Contents Evaluation Restoration and Remediation, and Large or Catastrophic Restoration. Also, note that Carpet Disengagement and Reinstallation has been moved back into the Appendix of the document. The IICRC S500 provides a specific set of practical standards for water damage restoration. It does not attempt to teach comprehensive water damage restoration procedures; rather it provides the foundation for basic principles of proper restoration practices. IICRC S500 does not attempt to include exhaustive performance characteristics or standards for the manufacture or installation of structural components, materials and contents (personal property). The IICRC S500 Standard and Reference Guide is presented using a two-part format: the standard itself and a supplementary reference guide. The procedural standard is featured in this first section, supported by the reference guide in the second section. The intent is to use the principles outlined in the reference guide as a tool to better understand and apply the standard itself. However, the reference guide is not considered part of this standard."