We either decide everyone gets to take personally judged risks or no one, otherwise it's a legitimised increase in the class divide
It's all done within the legal framework and guidelines though. He has so many tests done (before travel, every second day, on return as per guidelines) that I'm surprised he has any nasal mucosa left. He also quarantines per requirements on return. It's not a case of him swanning off ignoring the rules and regulations - these are conformed to by the letter.
Of course, you may not like the fact that international business travel is still occuring during a pandemic but you can't blame any individuals - all that would happen if DH decided to martyr himself and knock back work is that another UK-based engineer would be contracted for the job in question, so number of travellers overall would in no way be minimised.