CO2 leaves no residue and is non-conductive. Dry powder works but destroys sensitive electronics. Water or foam conducts electricity and will electrocute the user.

: Professional summaries like the COLREGs Assessment Guide provide nearly 180 questions and answers in PDF format.

: Correct responses to avoid collision, such as course alterations and speed adjustments. Visibility Standards

International Collision Regulations (COLREGs), including lights and advisory rules for various navigating circumstances.