BS ISO 20899:2018 pdf free

BS ISO 20899:2018 pdf free.Water quality一Plutonium and neptunium一Test method using ICP-MS
Through chemical separation, high uranium decontamination factor can be achieved but remaining uranium concentration is likely to be still above the typical 238Pu concentration expected in water.
In addition, this 238Pu concentration is expected to be lower than the LOQ reported. For this reason,current instrumentation is not suited for 238Pu measurements, in normal conditions. However,assuming that a collision-reaction cell could be installed onto a more sensitive instrument, such a newer instrument could be more suited for the separation of isobaric interferences.
For the determination of trace amounts, the prevention of all contamination or losses shall be of primary concern. Dust in the laboratory, impurities in the reagents and on the laboratory equipment which are in contact with the samples could be potential sources of contamination. The sample containers can lead to positive or negative bias in the determination of trace elements by superficial desorption or adsorption.
Perform the storage and pre-treatment steps (filtration and acidification) described in Clause 8 when sampling or immediately afterwards.
Sampling, handling and storage of the water shall be done as specified in ISO 5667-1, ISO 5667-3 and ISO 5667-10. Guidance for the different types of water is given in ISO 5667-4[12] to ISO 5667-8[21].
It is important that the laboratory receives a sample that is truly representative and has not been damaged or modified during transportation or storage.
Although the chemical separation is done to avoid common interferences (mainly with 238U and UH+effect at 239 m/z area), the potential interferences for the masses of interest should be reported in a separate table. It is recommended to measure the count rate corresponding to 238 m/z to assess if the amount of remaining 238U is sufficiently low so as not to interfere.
Before any sample measurement, measure the quality control solution (5.5). Ensure that the measured value of the concentration does not deviate from the expected value (within measurement limits). If the deviation exceeds the established measurement limits (optimum sensitivity, optimum stability),follow the recommendations of the instrument manufacturer and perform the optimization of parameters again.BS ISO 20899 pdf free download.