ASTM D618-00 pdf free.Standard Practice for Conditioning Plastics for Testing.
Unless otherwise specified, test materials conditioned inthe standard laboratory atmosphere in the same atmosphere.9.2 Unless otherwise specified, test materials conditioned inaccordance with Procedure B at room temperature conditions.Start the test as soon as possible, but do not allow more than 1/h to elapse between removal of the specimens from thedesiccator and the start of the tests.
Unless otherwise specified, test materials conditioned in,Unless otherWpsecsdures D and E immediately with a damp cloth,then with a dry cloth,and test them at room temperature. Specimens should only be removed from thewater as the tests are ready to be conducted. Start the testsimmediately and complete them as soon as possible.
Tests at Other Standard Test Temperatures:When tests are desired at standard test temperatures prescr1beuh. preferably imme with Procedure Athar 5 h prior the specimens at the test temperature for no more than 5 h prior to test,and in no case for less than the time required to ensurethermal equilibrium.
Selection of Conditioning Procedure:In the case of materials covered by ASTM specifica-tions，reference should be made thereto to determine theconditioning procedures to be used.In the case of all other materials, the choice betweenprocedures should preferably be based on the one that gives themost reproducible test results.
The report of any test referencing this practice shallstate:Conditioning procedure used,Conditioning time used, to the nearest 1/ h, if notspecified in the procedure,Temperature, to the nearest degree Celsius，and therelative humidity, to the nearest percent, of the atmosphere inthe vicinity of the specimen during the test, except that wherethe test extends longer than 30 min，the actual ranges oftemperature and relative humidity shall be reported, and Actual range of temperature and relative humidity ifthe standard tolerances are not used.
The conditioning procedures prescribed in this practiceare designed to obtain reproducible results and may givephysical values somewhat higher or somewhat lower thanvalues under equilibrium at normal conditions, depending uponthe particular material and test.To ensure substantial equilibrium under normal conditions of humidity and temperature,however, may require from 20 to 100 days or more dependingupon thickness and type of material and its previous history.Consequently, conditioning for reproducibility must of necessity be used for general purchase specifications and productcontrol tests.ASTM D618 pdf download.