Tenant complains about incense affecting her asthma. Help!

[Aaron Kirby]

We signed a lease for a new tenant on the second floor of a three family. The new tenant likes to burn sage incense. The third floor has asthma and claims that the sage is triggering her asthma and can’t sleep. Third floor would like the second floor to stop using sage, because on the lease it states that we are a smoke free rental property. Is incense considered smoke? Can I legally ask the second floor tenant to stop burning incense, candles, etc. Due to the no smoking policy? The third floor is threatening to make a discrimination claims if I allow the second floor to continue to use her incense. Please help, any thoughts on how to handle this situation... 

[Steve Hall]

I disagree with @Lynn M: You don't ask a tenant for anything. You tell them... (and always in writing.)

I disagree with @James Wise: You should never let issues between tenants take place in your units, especially if one of the tenants if violating the lease and the other is threatening to sue you.

Have you read this? https://www.sciencealert.com/incense-could-be-more-harmful-than-cigarette-smoke-researchers-find

Your lease should have clauses about health hazards, or open fire/burning. If not, it's time to fix your leases for the next time you renew. We all learn as we go...

If you can enforce this issue as a breach, be sure to follow the notice laws per your state.

If you don't have a provision in your lease about health hazards or burning/fire, I would inform tenant #2 (in writing, by certified mail, and posted to their door) that their actions are creating a potential health hazard for tenant #3 and that they are hereby required to cease and desist the burning of incense in their unit, immediately. I might add that I will waive any early termination fee, for the next 30 days, (notice to be provided within 3 days) if they wish to move out and find a facility that will allow them to burn incense.

I would also drop a hint (verbally / in person) that their future landlord(s) are going to call me for a reference and I would like to be able to tell them that "Yes, the tenant was very co-operative..." or "Yes, I would rent to them again".