ISO 14714 pdf download

ISO 14714 pdf download.Essential oils and aromatic extracts — Determination of residual benzene content 1 Scope This International Standard describes a method for determining the residual traces of benzene in essential oils and aromatic extracts, using static headspace gas chromatography. It applies to residual contents of around 1 0 31 0 26 (1 0 ppm) in the analysed product. 2 Normative references The following normative documents contain provisions which, through reference in this text, constitute provisions of this International Standard. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the normative documents indicated below. For undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC maintain registers of currently valid International Standards. ISO 356, Essential oils — Preparation of test samples. ISO 7609, Essential oils — Analysis by gas chromatography on capillary columns — General method. 3 Principle Analysis by gas chromatography of the static headspace on a capillary column, either by flame ionization detector or by detection by means of mass spectrometry. Determination of residual benzene content using external standard method (by calibration). 4 Reagents 4.1 Reference substance: benzene, of minimum purity 99 %, as determined by gas chromatography. 4.2 Diethyl phthalate, free from any traces of benzene, to be verified under test conditions. 5 Apparatus 5.1 Chromatograph, recorder and integrator See ISO 7609. 5.2 Capillary column, with the following characteristics: – length: 30 m to 60 m; – internal diameter: 0,20 mm to 0,5 mm; – stationary phase: methyl silicone type is recommended. 5.3 Flame ionization detector or mass detector 5.4 Headspace sampling device, for the injection of headspace vapours, comprising either 5.4.1 or 5.4.2. 5.4.1 Gas syringe system (manual), with leaktight locks. 5.4.2 Automatic injector equipment 7 Operating conditions 7.1 Chromatographic operating conditions 7.1.1 Injector temperature shall be 1 50 °C. 7.1.2 Oven temperature shall be maintained constant at between 40 °C and 60 °C for 1 5 min, followed by rapid temperature programming to elute any less volatile product. 7.1.3 Temperature of flame ionization detector shall be between 200 °C and 250 °C. 7.1.4 For flow rate of carrier gas and auxiliary gases, see ISO 7609. 7.2 Operating conditions for headspace sampling device 7.2.1 The sample shall be thermostatted at...