There are machines and chemicals that are used in commercial operations to sterilize feathers and down that are used for pillows, comforters, etc. Heat and steam can also be used. But unless they are feathers from a pet bird, or from farm fowl (domestic chicken, duck, goose, turkey, etc.), you do not sterilize them. If they are from wild birds, you do not even touch them. In the US, all native migratory birds are protected under federal law (Migratory Bird Treaty Act). It is illegal for anyone to possess a protected bird, its nest, its eggs or even its feathers unless they have the required federal and state licenses. It is also illegal to disturb an active nest. Penalties for violating this law include up to $500 and/or up to 6 months in jail for each offense. It doesn’t even matter if you did not mean to break the law: “A type of question that we commonly get involves well meaning people who want to rescue young or injured birds, secure feathers for artwork, or salvage eggs or nests