【国外标准】 Standard Test Method for Elapsed Time Calibration of Thermal Analyzers

5.1 Most thermal analysis experiments are carried out under increasing temperature conditions where temperature is the independent parameter. Some experiments, however, are carried out under isothermal temperature conditions where the elapsed time to an event is measured as the independent parameter. Isothermal Kinetics (Test Methods E2070), Thermal Stability (Test Method E487), Oxidative Induction Time (OIT) (Test Methods D3895, D4565, D5483, E1858, and Specification D3350) and Loss-on-Drying (Test Methods E1868) are common examples of these kinds of experiments.5.2 Modern scientific instruments, including thermal analyzers, usually measure elapsed time with excellent precision and accuracy. In such cases, it may only be necessary to confirm the performance of the instrument by comparison to a suitable reference. Only rarely will it may be required to correct the calibration of an instrument's elapsed time signal through the use of a calibration factor.5.3 It is necessary to obtain elapsed time signal conformity only to 0.1 times the repeatability relative standard deviation (standard deviation divided by the mean value) expressed as a percent for the test method in which the thermal analyzer is to be used. For those test methods listed in Section 2 this conformity is 0.1 %.1.1 This test method describes the calibration or performance confirmation of the elapsed-time signal from thermal analyzers.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.