Nope, a snake that size can EASILY restrain & kill a human, even a big strong guy (like this guy) is NOT safe.
I don't know of any exact rule for safety, since everyone has different size, strength, experience & issues, but if this guy works this snake alone, he's just an accident waiting to make a headline...& not a good headline for the snake-keeping community.
Many say to keep alcohol or vinegar on hand to make the snake release a bite, but that only helps if you can get a hand & arm free...And a person could be very dead before a group of people could get this snake off. Not saying that any snakes "want" to kill people...nothing further from the truth...but misperceptions do happen, & snakes may either be defensive or worse, food-aggressive. Can happen pretty fast.