My tenant leaves burning candles in apartment while she is at work!

I need some sage advice here from the blog. How would you treat this situation given that they are endangering the lives of 3 other families with this idiotic practice conducted behind closed doors. i only discovered it when I had to enter the apartment to replace an appliance that failed.
This seems so insane and I cannot stop thinking everyone is in danger because of them. It is in their lease not to leave candles unattended as well.  The NYFD warns against this. They are a nice couple in every other way but I feel i might have to start legal action to stop them.

A "you are in violation of your lease by burning candles" letter from an attorney familiar with NYC Housing laws is a good next step.

AKA: Cease and Desist letter. 

I'm confused, it sounds like you're the landlord or super? Just tell tel them straight up they can't do it. If you catch them with any candles lit or otherwise in the apartment after this warning you will evict them. You usually don't have to follow through on that threat.

I agree MOD. Why go to that step when a simple knock on the door letting the tenant know that it is illegal to burn candles unattended. If it continues, give them the legal letter and if that doesnt work then get an eviction notice. whynot seems a little too aggresive. 

I agree with @whynot_3, the legal letter is a smart move. What are your chances of being called in for another repair and seeing these candles again? If it doesn't happen, you wouldn't know if they continued burning them, other than by doing random checks during the day with no other reason to enter the apartment (or if the place caught fire).

In NY Housing Court, they call the letters Notices to Cure
http://www.nycourts.gov/courthelp/Homes/holdoverNotices.shtml

Such letters accomplish a few things.    If the tenant continues to burn candles while not home, you can show the letters to:

- Housing Court to demonstrate that you tried to resolve the matter without the court's assistance, but that didn't work.   As explained above, such letters are required before a Holdover Case can be initiated.

- A party that is attempting to sue you because there was a fire and they believe you knew of the tenant's actions, yet you took no action.

Here's more info about NYC Housing Court:   http://www.nycourts.gov/COURTS/nyc/housing/holdoverjudg.shtml

It doesn't say it on the webpage, but it is a miserable place, and I hope you and your tenant never need to visit it.

Why is she burning candles during the day when she is not home anyway?

Maybe Whynot_31 is right, a letter from the courts might be all you need and this sounds pretty urgent.

Such great advice. Last year I did express concern to them when I saw the unlit candle "alters" around the house and was assured they would only lite them while at home.

I gave them 5 months notice to leave. They left. all is good now. thanks everyone for the advice.

best of luck with your new tenants.