Inconsiderate Neighbors

When I moved into my apartment, my landlord said this was a quiet building.  I soon found out that was not the case.  Every other floor is quiet and clean, but mine has furniture lined throughout the hallways, along with trash.  My neighbors also smoke and laugh outside of my door.  Because of the small size of the building, they are well within their rights to smoke in the building, even though the landlord put up a "no smoking" sign.   Also, my lease says no smoking (in the apartment, which explains why they do it in the hallway). The furniture doesn't block the fire exit, so that is not an issue.  There's nothing in the lease about loitering in the hallway.

The landlord is here a few times a week and sees the ash trays, cigarette butts, and furniture.  

The people seem friendly but selfish inconsiderate. I told them I can't stand the smoke, and they suggested sealing my doors, which I did.  I thought about going to the landlord, but he seems to be friends with them.  I don't want any kind of retaliation as I don't know what kind of people I'm dealing with.

Has anyone ever been in this situation?  

The FDNY and DOB will issue violations and fines for stuff in the hallways.

They could learn about the situation anonymously via 311...

Thanks! I thought about that, but it's not blocking the exits. Also, they'd know I reported it.

Sometimes they issue violations for things like strollers, bikes, or kitty litter containers in the hall.

When they investigate a report, they try to protect the callers confidentiality.