I work in an old 3 story building. It was a department store, but was converted to a medical facility. We use half of the first floor for patients, and half of the second floor for storage. There are stairways and hallways leading to the storage part that have exposed asbestos insulation and peeling lead paint. Furthermore, one can freely travel the rest of the second and third floor.
Is this an actual OSHA violation. and if so, can certain places be marked "off limits" if not used, or do they also need to be sealed/repainted?
First of all, I would make sure my facts were right. That is, actual chemical tests confirm the presence of the suspect materials. There is a lot of peeling paint that has no lead, and a lot of fuzzy fireproofing that has no asbestos- regardless of age.
Assuming that these materials are present, well, what are you doing? You pretty much have to eat significant quantities of the paint to absorb the lead, and asbestos is a problem only when you inhale it.
If the stuff is just lying there, undisturbed as you walk by.... where's the risk? Can you protect yourself with a mask, while you scrape, vacuum the stuff out of your way? Maybe a coat of spray glue or varnish will keep it in place?
If you actually must disturb the stuff to any extent, then there ought to be a call made to the proper contractor, to reduce the risk.