how many feet does the fire dep need in order to keep a bike in the hallway

What does your lease say? The usual language would be that the landlord can make sure all ingress and egress is safe to your apartment and out into the common areas. So, if your bike even potentially causes a blockage then you should move it. If you do not, the landlord may do so.

Check with a lawyer in your locale to discuss more of the details.

Good luck to you.

God bless.

NOTE: This answer is made available by the out-of-state lawyer for educational purposes only. By using or participating in this site you understand that there is no attorney client privilege between you and the attorney responding. This site should not be used as a substitute for competent legal advice from a licensed professional attorney that practices in the subject practice discipline and with whom you have an attorney client relationship along with all the privileges that relationship provides. The law changes frequently and varies from jurisdiction to jurisdiction. The information and materials provided are general in nature, and may not apply to a specific factual or legal circumstance described in the question.