Never attempt to enter the building until the fire department or other authorized expert says it is safe.
After you have cared for wet items, usually by freezing, you can begin to consider treatment fo smoke damaged and charred items. Try to avoid touching charred items until ready to clean. Always wear latex gloves when handling sooty items. Use treated rubber sponges, One-Wipes, etc to remove most of the soot Transport items to a clean space and clean again. Valuable books, documents and works of art should be conserved by a professional. Some recovery services provide an ozone treatment to remove the smoky odor. There is some controversy about the usefulness of ozone. It is not recommended for fine art and hastens the deterioration of paper. This may be an option for a circulating, but not an archival collection.
Once everything is stabilized, you have the time to think and plan. What does your insurance cover, can you hire experts or will this be a local effort? Cleaning your site is vital. Once a book has been dampened or wet, it is much more susceptible to mold. Any areas that harbor mold are simply going to make the problem worse. Never put any of your collection back into an area that hasn’t been thoroughly cleaned. If you are not able to hire experts, the housekeeping staff of the local hospital may be able to tell you the best procedures to achieve the level of cleaning that must be done.