The smell of space

ISS Science Officer Don Pettit says:

"Then I noticed that this smell was on their suit, helmet, gloves, and tools. It was more pronounced on fabrics than on metal or plastic surfaces. It is hard to describe this smell; it is definitely not the olfactory equivalent to describing the palette sensations of some new food as "tastes like chicken." The best description I can come up with is metallic; a rather pleasant sweet metallic sensation. It reminded me of my college summers where I labored for many hours with an arc welding torch repairing heavy equipment for a small logging outfit. It reminded me of pleasant sweet smelling welding fumes. That is the smell of space."