This was on Evacuation, standard full online game.
Reproducibility: Possible, likely in the same area.
Hans' gas grenades were not causing any damage or poison effect on me in this area, same area as the blasted door:
I was at the bottom of the stairs when it went off and walked through without a scratch.
I have also avoided gas damage at least 2 other times in this area, not necessarily on the stairs but on the upper level.
Reproducibility: Possible, likely in the same area.
Hans' gas grenades were not causing any damage or poison effect on me in this area, same area as the blasted door:
I was at the bottom of the stairs when it went off and walked through without a scratch.
I have also avoided gas damage at least 2 other times in this area, not necessarily on the stairs but on the upper level.
Hans' gas grenades not damaging me
