For TEM method regarding blanks, how many field blanks are required?

In the context of the Transmission Electron Microscopy (TEM) method for asbestos analysis, the requirement for field blanks plays an important role in ensuring the accuracy and reliability of the results. The standard practice dictates that two field blanks are required.

Field blanks are crucial as they help to assess the level of contamination that may occur during the sampling process. By including two field blanks, it allows for a more robust evaluation of the potential presence of asbestos fibers or particles that could be introduced during the sampling, handling, or analysis stages. This dual approach enhances the quality control of the sampling methodology and provides a clearer picture of any background noise present in the data.

In laboratory practice, utilizing two field blanks gives a better statistical representation for identifying potential issues related to contamination, thus ensuring that the final data on asbestos levels remains accurate and defensible.