BS ISO 15651:2015 pdf free
BS ISO 15651:2015 pdf free.Nuclear energy
The following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
ISO/IEC Guide 98-3:2008, Uncertainty of measurement一Part 3: Guide to the expression of uncertainty in measurement (GUM: 1995)
The total hydrogen content is determined using a hydrogen analyser. The hydrogen analyser is based on the carrier gas method using argon or nitrogen as carrier gas. The samples to be analysed are heated up to a temperature of more than 1 770 °C in a graphite crucible. At that temperature, all volatile components are removed. The hydrogen containing compounds are cracked and released as hydrogen, oxygen, nitrogen, and carbon monoxide. The released gas is purified in the carrier gas stream, for example by oxidation and adsorption columns. The hydrogen is separated by chromatographic means and analysed in a thermal conductivity cell.
Sampling is done with a tube shaped powder sampler having an inner diameter of more than 2,5 times of the maximum powder particle size. The sample shall be exposed to ambient conditions for not longer than 5 min because alterations of the powder sample due to moisture adsorption or desorption or oxidation have to be avoided. The sample has to be stored in tight containers. The gas volume in the container should be as low as possible. In case the analysis is not performed immediately after the sampling, the sample mass has to be controlled before and after storage period prior to the analysis.These precautions can be relaxed if the analysis process is made under controlled gas environment (glove box environment.)When sampling the fuel pellets, ensure that pellets are not contaminated with H2; use metal forceps or pincers for sampling pellets. The sample should be representative for the manufacturing process (e.g. storage of the pellets).BS ISO 15651 pdf download.
