This specification presents the standard procedures for establishing the performance rating of wood-plastic composite (WPC) deck boards and guardrail systems (guards or handrails). The purpose of this specification is to establish the basis for code recognition of these products or systems in exterior applications where combustible construction is allowed. The general requirements foe these products shall be dictated by their performance in the following test methods: flesural tests; temperature and moisture effects; ultraviolet resistance test; freeze-thaw resistance test; biodeterioration tests; and fire performance tests. Deck boards shall additionally examined by: creep-recovery test; determination of unadjusted allowable load; mechanical fastener holding tests; and slip resistance test. In the same manner, guards and handrails shall additionally be analyzed through concentrated load tests, and one- and two-family dwelling requirements.