Never take your brain and common sense out of the equation.
There's a rule mandating PC1 at some places, but there's also a rule saying thou shalt not cause damage or hazard with your downwash. Pick your rule. For me, big chance of damage Vs very small chance of engine failure is an easy choice. I've lifted stuff with downwash and had the heart in the mouth moment wondering if it'll come through the main or tail rotor.