The Confirmation  Procedure (s) shall fulfil the following requirements:  - The Confirmation  Procedure (s) shall be Fit-for-Purpose , including the estimation of the MU associated with a quantitative Confirmation Procedure ; - The Confirmation Procedure (s) shall be recorded, as part of the Sample (or Sample  batch) record , each time it is conducted ; - The Confirmation Procedur e shall have equal or greater Selectivity  than the Initial Testing  Procedure  and shall provide accurate quantification results (applicable to Threshold Substances ).