ISO 12578:2016 specifies requirements for the components of glued laminated timber members for structural use. ISO 12578:2016 is applicable to products with a finished lamination thickness of not more than 50 mm. Although most glued laminated timber is made from coniferous species, this International Standard also applies to broad leaf species if the tests specified in this International Standard show that a satisfactory glue bond can be achieved. The basic requirements apply to structural members of all service classes; however, special precautions are necessary for service class 3, for example, the use of weather resistant adhesives (see 5.3). ISO 12578:2016 does not apply to the determination of strength and stiffness characteristics. Annex B contains informative materials for formaldehyde emission.