What is a requirement regarding sealed blanks in TEM sampling?

The requirement that sealed blanks must be carried with each sample set is critical for ensuring the integrity and reliability of the sampling process when using Transmission Electron Microscopy (TEM). Sealed blanks serve as a control measure to help identify any potential contamination that may occur during the sampling process. By including these blanks with each set of samples, technicians can compare results and confirm that the samples being analyzed represent accurate amounts of asbestos, free from interference from external sources.

This practice not only helps to verify the cleanliness of the sampling equipment and environment but also ensures that any detectable fibers found in the actual samples can be confidently attributed to the sampled material rather than a byproduct of contamination. Consequently, effective sampling protocols mandate that sealed blanks accompany each set of samples to provide a benchmark for evaluating contamination levels and to uphold the overall quality of the analytical results.