Opinions and suggestions for "General Test Method in Salt Industry-Determination of Iodine" (GB/T 13025.7-2012) / 中华地方病学杂志

In order to make the national standard method of "General Test Method in Salt Industry-Determination of Iodine" (GB/T 13025.7-2012) more standardized and strict,basing on work experience,literatures and books,the authors listed the details needed to be amended and completed,including method principle,writingof chemical equations,preparation and calibration of standard titration solution,blank tests,sample weighing and result calculation,starch indicator,etc.At the same time,we gave out our opinions and suggestions aiming to provide reference for standard methodologist in revising and updating the standard method.

Analysis of on-site quality control assessment results of iodine content determination in edible salt in Zhengzhou City / 中华地方病学杂志

Objective To analysis the on-site quality control assessment results of salt iodine content in Zhengzhou City,and to understand and master the actual professional abilities and level of grass-roots laboratory analyzers,and to search the problems and make improvement measures.Methods The total of 22 analyzers from 11 affiliated grass-roots laboratories of Zhengzhou City were gathered to take part in the on-site theoretical examination.The theoretical assessment was divided into five parts:measurement principle,application range,reagent preparation,key steps,and calculation formula of results.Parallel samples of standard materials were determinated in laboratory units,to evaluated operational skills,the problems during the process were recorded simultaneously.The content of the theoretical assessment and the rules for the assessment of on-site skills were based on the "Measurement of Iodine for the General Test Method of the Salt Industry" (GB/T 13025.7-2012).Results In the theoretical assessment,the correct rates of reagent preparation and key steps were 100％,and that of measurement principle,application range,and calculation formula of results were more than 80％.The main problems of operation skills were from liquid loading,sample weighing and titration operation,etc.One laboratory result of quality control sample exceeded the reference range and was judged to be unqualified.Conclusions The theoretical basis of some laboratory analyzers are not solid,the operational skills are lack of standardization.In view of the current situation,as the higher level technical guidance unit,it is necessary and responsible for us to formulate practical measures in training,guidance and assessment to help them improve business level and abilities.