This standard applies to interior wall and ceiling materials or systems used in cleanrooms, pharmaceutical manufacturing and storage areas, food preparation and storage areas and similar occupancies or other occupancies which are susceptible to smoke damage. Wall and ceiling materials or systems which are categorized for use in cleanrooms meet the requirements of Test Standard for FM Approvals Cleanroom Materials Flammability Test Protocol, Class Number 4910 and American National Standard for Clean Room Materials Flammability Test Protocol ANSI/FM Approvals 4910 in addition to the other requirements of this standard. These materials or systems produce low levels of smoke. Wall and ceiling materials which meet the requirements of this Standard and which are categorized for use in pharmaceutical manufacturing and storage areas, food preparation and storage areas and similar occupancies produce somewhat higher levels of smoke (when compared to those materials or systems which were evaluated for cleanrooms) but produce less smoke than materials and systems evaluated to the Approval Standard for Class 1 Fire Rating of Insulated Wall or Wall and Roof/Ceiling Panels, Interior Finish Materials or Coatings, Class Number 4880 or Approval Standard for Class 1 Exterior Wall Systems, Class Number 4881.