This standard specifies four methods for the determination of the Vicat softening temperature (VST) of thermoplastic materials: - method A50 using a force of 10 N and a heating rate of 50 K/h; - method B50 using a force of 50 N and a heating rate of 50 K/h; - method A120 using a force of 10 N and a heating rate of 120 K/h; - method B120 using a force of 50 N and a heating rate of 120 K/h. The methods specified are applicable only to thermoplastics, for which they give a measure of the temperature at which the thermoplastics start to soften rapidly. This standard differs from DIN EN ISO 306:2004-10 as follows: heating equipment, consisting of a fluidized bed, has been introduced as a new apparatus; Annex B (informative) "Comparison of VST results obtained with liquid-filled heating bath and fluidized bed" has been added; precision data have been extended and included as Annex C (informative) and terms have been added as clause 3. The International Standard ISO 306:2013 has been prepared by ISO/TC 61/SC 2 "Mechanical properties" (secretariat AENOR, Spain). The committee responsible for the European Standard is CEN/TC 249 "Plastics", the secretariat of which is held by NBN (Belgium). On the national level the standard is supervised by Working Committee NA 054-01-22 AA "Mechanische Eigenschaften und Probekörperherstellung" ("Mechanical properties and preparation of test specimens") of the FNK.