- The Initial Testing  Procedure  shall b e recorded, as part of the Sample  (or Sample  batch) record, each time it is conducted ; - All batches undergoing an Initial Testing  Procedure  shall include appropriate negative and positive quality controls prepared  in the matrix of analysis 13; - The Initial Testing  Procedures  for Non-Threshold Substanc es shall include appropriate controls of representative substance(s) at or below the MRPL ;  - The Initial Testing  Procedures  for Threshold Substances  shall include appropriate controls close to the Threshold  14;  - Results from Initial Testing  Procedures  are not required to consider the associated MU 14;  - The Laboratory  shall establish criteria, based on its method validation  and in accordance with its SOP , to evaluate results from an Initial Testing  Procedure  as a Presumptive Adverse Analytical Finding , which would trigger confirmation analyses.