What does the letter "B" in AA results mean

Question

I would like to understand why after calibration, when reading the results there is a letter "B".

dgrintuch · Answer

The FLAG with a letter of Capital B means the absolute concentration of the solution is less than the RDL ( required detection limit) and greater than or equal IDL ( instrument detection limit). 
 The list of "FLAG"s can be found by selecting the HELP in the tool bar, and searching for FLAG