Only at one situation the doors should be welded: Giving breathing space for your teammates after ALL OF THEM have passed through the door during kiting. Unfortunately, welding doors are never a solution in surviving zed horde since such action can constrain your escape/kite route for the entire team. The Support is proficient in welding doors and capable of repairing broken doors. The support is suggested to hold choke-points such as the long hallway found in containment station and biotics lab. It is recommended that you should initialize big zed take-down or co-operate with your teammates to take them down. On the contrary, if you are laning with a trash zeds specialist like the commando, swat and firebug. The support should prioritize trash zeds and medium zeds first as they could impose a major disturbance to your teammates when they are performing big zed take-downs. If you are laning with a big-zed hunter like the sharpshooter, gunslinger and demolitionist.
This is because target priority is not applicable to the support as such completely dependent on: I personally disagree with the target priority proposed by them. The above is the figure provided by the Tripwire Interactive Officials. The support is considered as a general-purpose perk who is responsible for handling zeds at close to medium range.
