0

 0 - No Assist

B

 B - Tow Assisted on Entry

C

 C - Tow Assisted on Exit

D

 D - Tow Assisted on Entry and Exit, and Assisting Vessel Locked Through

E

 E - Tow Assisted on Entry Only, then Assisting Vessel Lock Through

F

 F - Assisting Vessel Lock Through, Then Assisted Tow on Exit Only

G

 G - Separate Assisting Vessels Assisted Tow on Entry and Exit

H

 H - Tow Assisted to Secure on Wall Prior to Entry

M

 M - After Exit, Tow Assisted from Wall

P

 P - Assisting Vessel Powers Barges Through Lock

Z

 Z - Other (Remarks)