The science of cleaning and maintenance of installed textile floor coverings has grown significantly during the last 24 years. The IICRC first published the Standard and Reference Guide for Professional Carpet Cleaning (S001) in 1991 and revised it as the S100 in 1994, 1997, 2002 and 2011. The Sixth Edition of the IICRC S100 (2015) contains additional updates and revisions.