This specification covers the minimum requirements for gypsum formboard designed for use as a permanent form for poured-in-place reinforced gypsum concrete roof decks. Gypsum formboard shall consist of a noncombustible core, essentially gypsum, either mineral or organic, synthetic or natural. The face surface shall be specifically treated to resist fungus growth. Specimens shall be subjected to the following test methods: flexural strength; humidified deflection; core, end, and edge hardness; and resistance to fungi. Specimens shall be tested to determine thickness, width, length, end squareness, and edges and ends. The surfaces of gypsum formboard shall be true and free from imperfections that would render it unfit for use with or without decoration.

1.1 This specification covers the minimum requirements for gypsum formboard designed for use as a permanent form for poured-in-place reinforced gypsum concrete roof decks.

1.2 The values stated in either inch-pound units or SI (metric) are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system shall be used independent of the other. Values from the two systems shall not be combined.

1.3 The text of this standard references notes which provide explanatory material. These notes shall not be considered requirements of the standard.

1.4 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.