I think that law might apply to outboard tanks put in enclosed areas?? I’m not sure, but it makes sense for safety. A lot of the fuel line made for automotive use will kink easily on an outboard tank, especially if it gets hot in the sun – watch out for that! I recently found that some auto stores no longer carry much for fuel lines that can be used inside outboards either because cars haven’t used this stuff since the early 1980s when most all of them got fuel injection, requiring high pressure lines.
Dave