Given the nature of just how nasty bromine is, I imagine air freight would not be legal over any populated flight corridor. That'll make it impossible to fly into Korea.
Given the importance of DRAM, I imagine they would get their own plane if required.
I don't believe route limitation for dangerous goods is a thing. I looked on https://www.iata.org/en/publications/newsletters/iata-knowle...
Interestingly I asked both Claude and ChatGPT "does the Infectious Substances Shipping Regulations include anything about what routes for airfreight are allowed?" and it flagged it and wouldn't respond, although switching to Sonnet 4 allowed Claude to answer.