ABSTRACT
Reports of analysis are the written records of analytical services provided to others. Often, they constitute the only record of extensive effort and have more than transitory value. Data must be technically sound and defensible before it can be reported. The requirement for reporting is that all pertinent documentation is available and referenced so that it can be found at any time that it might be needed. Numerical data are often obtained with more digits than are justified by its accuracy or precision. So that it is not misleading, such data, when reported, should be rounded to the number of figures consistent with the confidence that can be placed in it. The number of significant figures to be used in reporting results is often a question. This will depend on the number of figures in the original data and the confidence limits to support the results.
