Name five forms of dust exposure that can cause extrinsic allergic alveolitis.

1. Cotton dust (byssinosis, Monday morning fever)
2. Moldy hay (farmer's lung)
3. Molds in air conditioners (Pandora's lung)
4. Moldy sugar cane (bagassosis)
5. Protein in pigeon droppings or feathers (bird fancier's lung)