EU A.1: Melting temperature/range

The melting point serves as an indicator for the physical state (liquid or solid) of a substance.

The purpose of this study is to evaluate the melting point or melting range by the capillary method using an electronic controlled heating system.

(The study does not need to be conducted below a lower limit of –20°C).


Study Design

Course of the test

Apparatus - Büchi B 545

A small amount of the test item will be heated in the electronic controlled sample block and the temperature of around the sample will be displayed. The sample will be observed visually while rising the temperature. The initial and final melting temperatures will be determined.

Preliminary Test:

The melting behaviour of the test item will be estimated in this preliminary test. Therefore, a sample of the test item in a glass tube will be heated from room temperature up to about 400 °C with a rate of approximately 10 °C/min unless a phase transition or reaction of the test item will be observed.

The sample will be observed during the experiment and the temperature will be read for each observation documented.

Main Test:

If in the temperature range investigated in the preliminary test, a phase transition of the test item is observed, the experiment will be repeated with a new test item aliquot in the immediate vicinity of the temperature of the phase transition observed. For the actual determination of the melting point, the temperature rise will be adjusted to a maximum of 1 °C/min at about 15 °C before and after the predetermined phase transition temperature. This experiment will be performed at least in duplicate.


As the phase transition of many test items takes place over a large temperature range [°C and K], it is often described as the melting range. If the difference between the temperature at the beginning and at the final stage of melting is within the limits of the accuracy of the method, the temperature at the final stage of melting is taken as the melting temperature [°C and K]; otherwise the two temperatures are reported as the two extremes of the range.

Guidelines and Literature

  • Commission Regulation (EC) No 440/2008 laying down test methods pursuant to Regulation (EC) No 1907/2006 of the European Parliament and of the Council on the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) (originally published as Council Regulation (EC) No 440/2008, corrigendum according to Official Journal of the European Union (EN) dated June 3, 2008, L 143/55), Annex, Part A, A.1.: “Melting /Freezing Temperature”, Official Journal of the European Union, L 142, Volume 51, 31 May 2008
  • Organization for Economic Co-operation and Development (OECD), Guidelines for Testing of Chemicals, Guideline No.: 102, “Melting Point/Melting Range”, adopted July 27, 1995