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Standard Interpretation

Standard: 2016
Section: V1M4, Section (b)


The above section of the 2016 TNI Standard states – "Except where the matrix precludes its use or when not commercially available, surrogate compounds shall be added to all samples, standards, and blanks for all appropriate methods." The term "appropriate" is unclear. Is it the intent of the 2016 TNI Standard to require surrogates for methods like EPA 300.0, which does not require a surrogate, but is similar to EPA 300.1, which does require a surrogate?


If a method does not require surrogates, it is not the intent of the Standard to require them.