AASHTO M230:07(2020) Standard Specification for Expanded and Extruded Foam Board (Polystyrene).
5.1. Normally, extruded polystyrene foam boards shall be either 610 by 2440 mm or 1220 by 2440 mm. with the thickness being specified by the user.
5.2. The permissible ‘ariation,cfroni the ordered dimensions shall be asfi.llows (ASTM C’578):
5.2.1. Length ±0.8 mm per 305 mm of length.
5.2.2. Width ±1.6 mm per 305 mm of width,
5.2.3. Thickness ± 1 .6 mm per 25 mm of thickness (Note I).
Note 1—When used for insulation, the thickness of board used shall be based on heat flow theory and local conditions.
6.1. The physical properties enumerated in this specification shall he determined in accordance with the folio H.’ing methods of the American Society for Testing and Materials (AS TM):
6.1 .1. Compressive Srrength—ASTM Dl (2 1. Procedure A, except that the compressive strength shall be determined when the specimen is compressed 5 percent of measured thickness or at the first major load deviation, whichever comes first. A major load deviation shall he that point on the stress— strain curve where the stress load drops significantly below the normal stress fluctuation characteristic of the material under test (Note 2).
Note 2—Construction requirements should specify a smooth surface on which the board is to be placed to prevent point loadings; wooden skewers or piles of non-frost-susceptible sand or gravel used to hold the boards from “separating” or “shoving” during covering; and a minimum of 250 mm of granular material above the insulation for “stress absorption” or prevention of crushing of the insulation by construction traffic. An on-site test with the proposed methods of construction,including layer thickness and construction equipment, is recommended to ensure that there is no separation of the boards nor crushing of the insulation. The potential for differential icing should be taken into consideration when selecting the depth of cover over the extruded foam board.
6.1.2. Oxygen bidex—ASTM D2863. This test shall he used to establish the minimum oxygen index.
6.1.3. Waler Absorpiion—ASTM C272/C272M.
6.1.4. Thermal Resistance—Test in accordance with ASTM C177 or ASTM C518. Tests shall be conducted with a temperature differential of 28 ± 1°C.
6.1.5. Density—Test in accordance with ASTM C303 or ASTM D1622/D1622M.
7.1. Health and Safety—Each manufacturer has a duty to warn when the shipment, storage, installation. use, or ultimate disposal of a product may expose individuals to health or safety hazards. The manufacturer shall provide the user with appropriate information regarding any known hazards associated with the recommended handling and use of the product. and shall recommend the protective measures to be employed in its safe utilization.AASHTO M230 pdf download.