ISO 18227:2014 pdf free
ISO 18227:2014 pdf free.Soil quality一Determination of elemental composition by X-ray fluorescence
Anyone dealing with waste and sludge analysis has to be aware of the typical risks that this kind of material presents irrespective of the parameter to be determined. Waste and sludge samples can contain hazardous e.g. toxic, reactive, flammable, and infectious substances, which could potentially undergo biological and/or chemical reaction. Consequently, it is recommended that these samples should be handled with special care. The gases that can be produced by microbiological or chemical activity are potentially flammable and pressurize sealed bottles. Bursting bottles are likely to result in hazardous shrapnel, dust, and/or aerosol. National regulations should be followed with respect to all hazards associated with this method.
The X-ray fluorescence spectrometer shall comply with international and national regulations relevant to radiation protection.The person responsible for managing or supervising the operation of X-ray equipment shall provide evidence of his knowledge of radiation protection according to national regulations.
After a suitable preparation, if necessary, the sample is introduced into an XRF spectrometer and excited by primary X-rays. The intensities of the secondary fluorescent energy lines specific for each element are measured and the elemental composition of the sample is determined by reference to previously established calibration graphs or equations and applying corrections for inter-element effects. The calibration equations and inter-element corrections are established using pure reagents and/or series of internal or reference materials providing they meet all the requirements of the relevant preparation technique.
Matrix effects occur when the X- ray fluorescence radiation from the analyte element is absorbed or enhanced by other elements in the sample before it reaches the detector. In the case of complex matrices,these effects generally have to be corrected.
Spectral artefacts, e.g. escape peaks, sum peaks, pulse pile up lines, dead time, and Bremsstrahlung correction, are accounted for by the provided software. Spectral artefacts differ for energy dispersive and wavelength dispersive XRF spectrometry.
Particle size effects can be reduced by milling the sample, and both particle size and mineralogicaleffects can be eliminated by preparing bead samples. It is vital for quantitative analysis that the same sample preparation procedure is applied to both the standards and the samples to be analysed.ISO 18227 pdf download.
