1.1 This specification covers structural cementitious panels. Structural cementitious panels are non-combustible, water durable, fiber reinforced inorganic composite panels intended for use as structural panels. Structural cementitious panels can be used as floor, roof and wall sheathing when fastened to supports spaced in accordance with the appropriate span rating.

1.2 This specification defines minimum performance requirements for structural cementitious sheathing panels with respect to structural performance, dimensional stability performance, dimensional tolerance, noncombustibility, surface burning characteristics, long-term durability, water durability, mold resistance, density, moment capacity and bending stiffness.

1.3 This specification also defines a policy to assure on-going product quality by detecting changes in panel properties that may adversely affect panel performance. Required audits of quality activities by a third party quality assurance agency are also defined.

1.4 The values stated in either inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard.

1.5 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 and health practices and determine the applicability of regulatory limitations prior to use.