Usually greeting by saying 'you alright' starts off a convo or at least makes it less akward by acknowledging the other person. Then either just talk about whatever your both doing that forced an interaction to happen.
I used to dread new environments and meeting people, but since uni/work has me going to alot of different sites it isnt as scary as it looks. Greet them, introduce yourself, and just keep on the same topic of whatever the other person is talking about unless you lead the convo
Usually just acknowledging the other person makes all the tension go away between you two.