IMO resolution MSC.333(90): On ships which are built on or after July 1, 2014, underwater locating devices must ensure a regulatory transmission time of at least 90 days.

The PT9 C-PROOF is a seawater-proof underwater locating device according to SAE AS 8045.

BLUE90 transmits for 90 days and satisfies the latest requirements under TSO/ETSO-C121b, which is applied to all aircraft worldwide since January 1, 2018.