Wednesday, December 3, 2014

Do-it-yourself Mold Testing?

There are many jobs that can be done by non-professionals, the do-it-yourselfers.  Often it requires a little education and/or instruction and you are off and running.  However, without proper or sufficient knowledge or confidence, instead of running, you could be just spinning your wheels.

The mold testing kits that are advertised on line are pretty much useless.  Results tend to be skewed and can be misleading if you are being lead anywhere at all.  These kits usually consist of Petri dishes that are to be set out in strategic locations for a period of time and then sent to a lab for culturing and a report of findings.  The findings will tell you that you have viable mold spores in your house and will give you some types present.  Well, of course you have mold spores in your house.  Mold spores are everywhere.  Put an orange out on a counter for a few days and you'll discover the same thing (the green mold is likely a species of Penicillium).  The molds detected by this method are the spores that happened to fall into the dish.  So this method of testing for mold is not so effective.  You find there are some types of mold spores in the air.  So what can you do with that?

If you want to find out if you have a mold problem in the ambient air you are better off hiring a professional to perform an inspection and to do testing that is appropriate to the situation.

There are conditions, however, where sampling yourself could be useful.  This involves taking samples from a surface.  Dark patches or spots might be mold or they might be something else.  There have been times when I have seen something on a surface that I was pretty sure was mold but discovered I was wrong when I got the test results.  And this is after 16 plus years working in this field.

Do you want to know if those spots on the wall, or on the ceiling or under the baseboard or on the underside of the carpet are mold?  You can sample it by following the simple instructions we provide along with the sterile swabs we would send at your request.  Once you take the sample or samples and send them to us, we request that you also provide photos of the areas of concern.  We send the samples to an independent laboratory for analysis by direct microscopy.  When we receive the lab report we do our own analysis based on the report, the photos provided and our own extensive knowledge based on nearly two decades of experience and study.  We then make recommendations on actions to take if any are indicated.  The recommendations are only based on the information we have.  It might be as simple as scrubbing spots off the wall and taking measures to reduce the humidity in the room.  Or it could be a recommendation to have a professional perform an inspection and possibly further testing.  If no mold is detected and we are certain that the sample has been taken correctly and from the right location, we will recommend no further action.  Taking a sample with a sterile swab is not difficult and often it is possible by looking at the tip of the sample to determine that the sample was taken properly.

As long as you have some confidence and trust in the professional doing the evaluation, this is a pretty inexpensive path to take for answers to conditions that might prove to be problematic to health.  There is also the peace of mind that can result when you find there is nothing at all to be concerned about.

I do want to note that any recommendations would be limited to the actual data available or provided and cannot be accountable for incorrect conclusions based on missing data.


  1. I agree that mold testing should be done by a professional. Without proper knowledge and training, you are putting your health at risk by performing mold testing by yourself. It is in your best interest to hire a professional for such a task.

    Susan Hirst |

  2. You are correct overall, but there are cases whereby just having a professional oversee testing can be sufficient and cost saving. My point is that usually just putting out a Petri Dish is not particularly helpful. Thanks for your comment.