Plumbing problems can escalate pretty rapidly if you leave them alone. A small leak today could result in a lot of water damage if you don't catch it early. This is especially true for mold, since it poses a respiratory threat to anyone in the vicinity, and especially those with allergies. Therefore, it is critical that you are able to identify the signs that you have mold.
The health problems caused by mold can also serve as a valuable symptom in helping you diagnose the situation. If people in your building are having respiratory problems, especially in certain parts of the building, then you should check the ventilation. If that doesn't pan out, make sure to take a look at the plumbing to see if there is any mold. If you have pipes that run near vents in the walls, that could potentially be the source of your problem. If the mold has spread from an area with heavy moisture via the ventilation, then the entire building might be at risk.
Scent of Mold
Long before respiratory symptoms emerge, you might be able to actually smell the mold if you are lucky. Try to check for such a scent under sinks and other accessible pipes. Even if you can't actually see the mold, a strong smell can indicate a large colony in the vicinity. You should hire an expert to determine whether or not you actually have mold and what steps will need to be taken to remediate the mold.
Leaks and Water Damage
Any area that has a lot of moisture can lead to the buildup of mold. This is doubly true for areas that are warm and dark. If you do get a leak, then you must fix the leak immediately and make sure that you totally clean up the excess moisture. The longer that stagnant water sits, the higher your chances of developing mold will be.
In this vein, it's important that any moisture is cleaned up as quickly as possible, even if you don't have a leak. Showers, bathrooms, and underneath sinks are all common places for small amounts of water to sit in the dark for long periods of time. Frequently check such places in order to minimize the risk of mold popping up and spreading. A little diligence now could save you a lot of time and money cleaning up mold later. Visit a company like DiRosato Plumbing and Heating if you have plumbing problems in your business.