The Laboratoire des Sciences du Climat et de l’Environnement (LSCE) has operated a radiocarbon dating laboratory for almost 70 years. It has evolved from a traditional ß-decay counting to an accelerator mass spectrometry facility. In 2015, the LSCE received a major upgrade with the installation of a MICADAS. This evolution required adjustments in sample preparation to match the new capability to date samples as small as a few tens of µgC. We summarize here the sample cleaning procedures and the chemical purification or extraction treatment that we apply to the samples. We also report values of blank and reference materials of different matrices that match the large diversity of samples handled at LSCE.