Maybe, if she smokes enough, there will be enough second-hand smoke floating around that they'll go off regardless of whether or not it's a result of her actually blowing the smoke that way.

If nothing else it gives her a good excuse to keep smoking. Not that she really needs a better excuse than Giant Wall of Child Death.

it's nice to meet you too.

She writes it out and holds it up, same as before, but instead of writing out a more direct response she considers her cigarette for a moment. She knows it won't work, but well. It's going to be a long night. So she inhales from it very deeply, and does in fact try to exhale towards the detector again. It gets closer this time, but still shows no signs of being enough to set it off.

It does make her smile slightly though.