I wouldn't worry about fire: it seems to be quite modern so most likely has quite some fire equipment and concrete. Common parts from the pictures don't seem to have much flammable stuff. Last time I stayed in London was in a hotel assembled from multiple old 3-4 floors buildings and multiple old wooden staircases, like to go to your room you had to go to floor 2 then end of a corridor then to floor 3 and right left and stuff like this in 1-person wide corridors and stairs. There I was scared of a fire because there was definitely a feeling of no way to escape fast.