Calculating Uncertainty in Complex Air Sampling

Elad Shelly, A.S Research Services LTD, Ma’ale HaHamisha, Israel
Naomi Perl, A.s Research Services Ltd, Maale Hahamisha, Israel

In most analytical laboratories, in order to calculate the uncertainty, one must repeat the test sufficient number of times.

However, in the field of sampling and particularly in the field of sampling from stationary sources (e.g. stack) calculating the uncertainty is much more complex, the main reasons are: first, in stack sampling enormous number of measurements is taken over large interval of time, each one of them can impact the uncertainty. Second, facilities processes are not fixed during time and space and therefore in repeating a test we might not necessarily expect similar results. Third, extracting the samples from the source involve harsh conditions, usually in high, noisy and uneasy working area, so parallel tests is hard and expensive to perform. Forth, since reported result is a combination of all other measurements (and different personel for the field and laboratory), it is hard to evaluate the influence of each measurement on the overall uncertainty. Therefore, in light of these obstacles, we developed a unique and complex model for evaluating the uncertainty of complex sampling. The model brings in to account the major uncertainty components according to their appearance in the equation of the sampling method and is built in a way that gets the uncertainty for each particular result.

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Short Biography of Presenting Author

Elad Shelly 

Serves as the QA/QC manager in the past 6 years at  A.S Research Services LTD.

Elad shelly has participated in numerous number of sampling campaigns for the industry and for the Israel ministry of environmental protection.

Since 2013 Elad has given on behalf of A.S Research Services the technical support for the Israel ministry of environmental protection at their stack sampling results.

Elad holds a M.Sc. in environmental science from the Hebrew University, and B.Sc in environmental science and geography from the Hebrew University.