What standard must wood floor systems adhere to if not designed and constructed in accordance with the international residential code?

Wood floor systems that are not designed and constructed following the International Residential Code (IRC) must adhere to the American National Standards Institute (ANSI) and the American Wood Council's National Design Specification (NDS) for Wood Construction. This standard outlines the requirements for the design and use of wood materials in construction, providing guidelines that ensure safety, performance, and reliability.

The NDS covers essential aspects such as load-bearing capabilities, the type of wood used, and its treatment, promoting consistent and effective practices in wood construction. Because the IRC is a model code that establishes minimum safety regulations for residential buildings, when systems deviate from these guidelines, the NDS serves as a benchmark to maintain safety and performance standards.

While other options may refer to different standards or guidelines, they do not specifically pertain to wood floor systems in the context of building construction. For example, ASTM D198 relates to the testing methods for the static bending properties of lumber, but it's not a comprehensive design standard like the NDS. ISO 9001 is a quality management standard applicable across industries, and NIOSH guidelines focus on occupational health and safety rather than construction specifics. Thus, the NDS is the correct standard for wood floor systems not designed according to the IRC.