A comparison of the various methods for calculating limit of detection (LOD, lower line in a pair) and limit of quantification (LOQ, upper line in a pair). The four methods compared are described in Section 4. The method using blank + low concentration sample is the most reliable, and consistently produces acceptable LOD and LOQ values for most practical purposes. The blank only method is a close second, but can under-estimate the LOD and LOQ. The calibration curve method results in very conservative estimates, while the RSD limit method is inconsistent with some extremely low LOD and LOQ values.