Is this the complete staircase and window from the other image? I like the dark shadows fading into light and fading dark again. Normally, I would have suggested lightening it up some but with this, I think it works just like it is.
Bit grainy and I agree a little dark but nice subject. BTW my recommendation when loading shots for C&C is to make them smaller for easier loading and viewing longest size 600 pix works well. (save as a smaller version so you keep your original size)
Industrial landscapes are fantastic to shoot and you have many of the right ideas going for you with this image. However, the natural window light falling onto the stairs could have been used more strategically for the success of the photo. Looking at this, I wonder if you spent quite a bit of time at the location, maybe going back at several different times of the day to check how the light looked and trying different exposures and POVs. Or did you just see this one time and shoot it? I feel as though it is probably the latter.