Ensuring accuracy of the results is essential if GEOTRACES is to build a meaningful global dataset. To this end, the [https://web.archive.org/web/20120716041115/http://www.geotraces.org/science/intercalibration] Standards and Intercalibration (S&I) Committee is in charge of securing that truthful and precise data are generated in the GEOTRACES Program through the use of appropriate sampling protocols, analytical standards and certified reference materials, and the active sharing of methods and results.
Since the concentration, activity, or chemical speciation of a trace element or isotope can be affected by sampling methods, sample handling, and analytical determinations, GEOTRACES follows the strategy of cruises to occupy a common station along their transects. At the same time two U.S.-led cruises (2008 and 2009) provided samples for intercalibration to laboratories from many countries. Seawater samples are available for use by other labs that wish to join this effort. 
Simple data comparisons like depth profiles show whether there are disagreements and, if so, the investigators can examine their methods and even data work ups to identify and remedy the problems.