It was obviously a civilian technician. I once knew a guy who got is hair caught in a drill press and never grew it long again afterwards.

OTOH, they don't say the guy should have had short hair. Instead they talk about "hair control requirements". As a long haired guy myself I take restraining my hair around moving machinery very seriously. Better to tie hair back, braid it, or even wear a bun than to get it caught in rotating machinery. Better to look girly than get scalped!