Anonymous ID: c05dad Oct. 4, 2020, 9:36 a.m. No.10917265   🗄️.is 🔗kun

>>10917248

The plain yellow flag ("Quebec" or Q in international maritime signal flags), perhaps derives its letter symbol for its initial use in quarantine, but this flag in modern times indicates the opposite—a ship that declares itself free of quarantinable disease, and requests boarding and inspection by Port State Control to allow the grant of "free pratique".[2]

 

https://en.wikipedia.org/wiki/Yellow_flag_(contagion)