Differential thermal analysis screening tests

Differential Thermal Analysis (DTA) A sample and inert reference material are heated at a controlled rate in a single heating block. This test is basically qualitative and can be used for identifying exothermic reactions. Like the DSC, it is also a screening test. Reported temperatures are not reliable enough to be able to make quantitative conclusions. If an exothermic reaction is observed, it is advisable to conduct tests in the ARC. 

Differential thermal analysis (DTA) Chemical testing technique that produces similar data to DSC. DTA uses temperature differences to generate test results DSC has largely replaced the DTA technique as a screening tool for obtaining chemical hazard test data... 

Initial Screen. Our initial screen is summarized in Table II. It consists of two test methods, Differential Scanning Calorimetry (DSC) and Differential Thermal Analysis (DTA). In both of these methods the sample is exposed to heat, and thermal changes in the sample are recorded. Heat flow into and out of the sample is recorded in DSC, and the temperature difference between the sample and a reference is recorded in DTA. 

Several small-scale screening tests are characterized by the small sample sizes they require (0.01-10 g) and by the speed with which they can be performed. They include differential scanning calorimetry (DSC) and various forms of differential thermal analysis (DTA) the insulated exotherm test (lET), decomposition pressure test (DPT) and the ICI 10 g sealed tube test. Commercial variants of such tests are also available. 

It was outlined in chapter 2 in detail that screening tests primarily have the purpose, to provide a first characterization of the safety relevant substance properties as part of the basic assessment. It was further explained that the determination of the thermal stability of a substance is of the greatest importance. The most fi-equently used methods for this puipose are those that investigate thermal stability using very small amounts of sample material only. The most widely used test equipments to perform such investigations are the DTA ( difference thermal analysis ) and DSC ( differential scanning calorimetry). 

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