Mold in A/C duct? - Need some opinions

[Jay Dean]

I will preface this post by saying that I am an Engineer with some experience on environmental matters.

Black / dirty air vents and ducts in my condo rental spotted by a prospective tenant expecting a baby.  I am not looking to cut corners or poor boy this problem.  I would not put any tenant in a potentially unsafe situation.

I am trying to get an understanding of how this is handled once it is confirmed that I have mold (if I do).  I expect there is a duty to fix and / or duty to notify but I don't know for certain.

This is a modest 1 / 1 condo with the A/C unit directly over the bathroom.  I expect part of my problem is the proximity to where people potentially take hot steamer showers.

Appreciate any feedback or war stories on this issue.

Thank you.