To avoid it, either drop a bigger item (like an Armor) in front of the Terminal and climb/mantle upon it, or cast a very useful Energy Reflection Power to absorb some of the damage.

Also, mind the electrocuting floor beneath each Terminal when placing the Barriers. Make sure you place more than one Barrier though, as their damage is quite high. It can block her Avatars' Energy shots with ease while you hack. This Power is effective in the final battle against SHODAN, especially during hacking shield's Terminals.This it is recommended to cast two Psi Walls with a small distance between them.

Should an enemy get too close, its projectiles can get on the other side of the Barrier.Standing on the Barrier also allows you to use Ranged Weapons against blocked/trapped enemies.Alternatively, it's possible to mantle the Wall and drain enemies' health from there. Ideally, a small gap between the Psi Barrier and the nearby surfaces should be left for easy aiming.

However, the enemy typically needs to be close to the outer side of the Wall to be targeted.

The Ability synergizes with Soma Transference by trapping an enemy with the Barrier and draining all of the foe's Hit Points away.

This is a good combat avoidance Power.

System shock 2 btrain of the many