UL 1479 Fire Tests of Penetration Firestops

Standard: ASTM D7032 Standard Specification for Establishing Performance Ratings for Wood-Plastic Composite and Plastic Lumber Deck Boards, Stair Treads, Guards, and Handrails

Scope: This specification covers procedures to establish a performance rating for wood-plastic composite and plastic lumber for use as exterior deck boards, stair treads, guards, and handrails. This specification aims to establish a basis for code recognition of these products or systems in exterior applications.

  • The plastic component of wood-plastic composites and plastic lumber covered by this specification consists primarily of thermoplastics.
  • Deck boards, stair treads, guards, and handrails covered by this specification are permitted to be of any code-compliant shape and thickness (solid or non-solid).
  • Wood-plastic composites and plastic lumber are produced in a broad range of fiber and/or resin formulations. It is recognized that the performance requirements in this specification are valid for any material or combination of materials used as deck boards, stair treads, guards, or handrails.

Products: Wood-Plastic Composite (WPC) Deck Boards, Stair Treads, Guards/Guardrails, or Handrails

Procedure: ASTM D7032 includes both material and structural testing.

Material testing is conducted on all product types and for various end-use factors, such as:

  • Temperature effect (+125°F and -20°F)
  • Moisture effect
  • UV resistance (ASTM G154 or ASTM D2565/ASTM G155)
  • Freeze-thaw resistance
  • Biodeterioration – Fungal decay resistance per ASTM D1413, ASTM D2017, or AWPA E10
  • Biodeterioration – Termite resistance per ASTM D3345 or AWPA E1
  • Surface burning characteristics per ASTM E84

Deck board testing includes:

  • Flexural performance for establishing allowable load with end-use adjustment factors
  • Concentrated load for stair tread applications
  • Creep recovery
  • Fastener testing per ASTM D1761 or similar (withdrawal and head pull-through)
  • Slip resistance testing (when required) per ASTM F1679 or similar


Guardrail structural performance testing includes:

  • Infill load
  • Uniform load (top rail)
  • Concentrated load (mid-span of top rail, end of top rail, top of post)

Result: Completion of all applicable tests in ASTM D7032 is intended to form the basis for code recognition of these products or systems in exterior applications.

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