ASTM D7032:2006 pdf free download – Standard Specification for Establishing Performance Ratings for Wood-Plastic Composite Deck Boards and Guardrail Systems (Guards or Handraills).
4.63 Criteria—The average change in properties between the exposed and unexposed specimens shall be calculated as a percentage and reported. Condition of acceptance is the average flexural strength of exposed test specimens and shall be within 10 % of the average flexural strength of unexposed specimens. For deck boards, if the decrease exceeds 10 %, the deck board span (or load rating) shall be reduced by the amount in excess of 10 %. For guards or handrails, if the decrease exceeds 10 %, the test loads for the guards or handralls shall be increased by the amount in excess of 10 % (see X1.3).
4.7 Freeze-Thaw Resistance Test—To determine the mechanical property degrade after freeze-thaw exposure, a minimum of five (5) specimens shall be subjected to the following exposure cycle. Whenever possible the test specimens shall be prepared using the full cross section of the as-manufactured product. Test specimens shall be submerged underwater (using weights to hold them down, if necessary) for a period of 24 h. The specimens shall then be placed in a freezer at —20°F (—29°C) for 24 h. After being subjected to freezing, the specimens shall be returned to room temperature for a period of 24 h. This process comprises one hygrothermal cycle. The above procedure shall be repeated two more times, for a total of three cycles of water submersion, freezing, and thawing.
4.7.1 A minimum of five (5) exposed and five (5) unexposed specimens shall be tested in accordance with 4.4. If more than one component is being evaluated (for example, deck boards and guard rail components) and all materials are manufactured from the same materials, then freeze-thaw testing of only one component is required.
4.7.2 Criteria—The average change in properties between the exposed and unexposcd specimens shall be calculated as a percentage and reported. Condition of acceptance is the average fiexural strength of exposed test specimens and shall be within 10 % of the average flexural strength of unexposed specimens. For deck boards, if the decrease exceeds 10 %, the deck board span (or load rating) shall be reduced by the amount in excess of 10 %. For guards or handrails, if the decrease exceeds 10 %, the test loads for the guards or handrails shall be increased by the amount in excess of 10 % (see X13).
4.8 Biodeterioration Tests—Termite and decay testing shall be required for deck board, guard, and handrail products containing wood, cellulosic, or other biodegradable materials.
4.8.1 Fungal Decay Resistance Test—Resistance to fungal decay shall be determined in accordance with Test Methods D 2017, D 1413, or APWA El.
4.8.1.1 Criteria—Examination of test blocks shall reveal decay resistance equivalent to that of preservative-treated or naturally durable wood products used in identical applications, as measured by visual inspection, and average weight loss.
Nat! 4—This is an accelerated laboratory decay teaL Results are subjective and comparisons between tests and materials should be used with caution. However, uan specimen weight losses greater than 5 %, or significantly greater than controls, should be cause for concern.
4.8.2 Termites—Test Method D 3345 or AWPA El shall be used for evaluation of resistance to termite attack.