I have a non-uniform nice black jacket that I will use. There’s no company approved anything for this level of cold.
Unless you can afford the $450 leather jacket. And even then....
That aside, long johns and thermal undershirts are a must. Gloves (nothing too fancy because it’s gonna get dirty opening panels), and a face mask, which is something I should get.
For the slippery ice, I do the penguin waddle and a prayer.
The ORD ground crew only spends 5 minutes outside before they swap crews, or so I’ve been told.