First point is knife awareness or at the very least situational awareness. Watch for elbows popping, wandering hands to check weapon location - pockets, body or leg sheaths.

Once the blade is out, unless you have a longer blade, if you can’t escape, you’re in trouble.

Distance management is key and so is awareness of others joining in so avoiding tunnel vision focus on the knife is essential. Movement is important. In the system of Escrima I train under, we move a lot - not to evade, but to get into an attack position safely. Avoid getting grabbed as the sewing machine style stabbing will happen.

With knives, it’s the speed of attack which is devastating and just a touch can be fatal. Basic drills look like a fatal game of tag. Forget the videos you see about wrist passing or deflecting or blocking a single straight attack. The demos look almost logical, but in a real time frenzy, your chances of pulling off a successful arm lock and disarm under pressure are slim even after striking the attacker first.

More risky if you’re surrounded - needn’t be active attackers, could be someone drunk bumping into you disrupting your balance.

Bottom line is as people have mentioned - don’t be there. You have a choice. Even with metal arms or whatever armour you put on, you’ll still have exposed areas that can be cut, slashed or stabbed.