Can someone give me a little advice on this one. Just heading out to do air quality/mold sampling in an apartment 4th floor. Outdoor sample?? Never done an apartment building so…
I say yes, you need a control sample (outside), or the results are not worth much.
I believe the OP was trying to determine where the outdoor sample should be collected. I’m assuming the apartment building is a mid or high rise building and the question may have been - collect the sample outdoors at the ground level, from a window, from a balcony, from the common hall outside the apartment?
I am not IAC2 certified but would guess the outdoor sample should be collected from the outside air which is most likely to enter the apartment, so if a mid or high rise building - from a window or balcony.
I would be interested to hear what the IAC2 certified guys say.
Got it done did it out the front foyer doors of the building (long extension cord) all is good. Thanks for the help.
What floor of the building was the apartment located?
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It was on the 4th floor out of six. First time for an apartment building test, but if I start to get a few more than that could be an option.
The common practice is taking an outside sample at least 20 feet from any buildings. The IAC2 standard allows you to test closer, but factors in you picking up mold on the outside of the building by taking two outside samples and averaging the results. Keep in mind, you are trying to take as clean of samples, as possible, under the most normal conditions, as possible.
Talked to Pro Lab and explained the situation and the they said no problem. Just mark it down on chain of custody as a controlled sample. Also it is snowing very hard here right now temperature is -10 degrees celsius.
Thats about 20 degrees fahrenheit.
I don’t believe taking control samples when temperatures are that cold are recommended. I’m afraid your results may be skewed.
Zefon Air O Cell states their product should not be used in temperatures in below 32 degrees F/0 degrees C.
John is right. I do not take an outside sample no colder than 40 degrees F. You got to factor in the velocity of the air dropping the temperature down some when pulled through the cassette. Also remember when there is snow cover, an outside air sample is not taken.
Also I have learned along time ago not to go by what Prolab says, the hard way, when I first started out. You are only as good as your lab.
Cliff, James knows his stuff on this one. Having him chime in on a mould question is perfect.
James, do you use a local lab or do you fedex samples somewhere? If you dont mind sharing who do you use?
First 4 words negate the whole thing for me…
There is no local lab in my area. I am too rural.
I use Springfield Indoor Air Quality in Springfield, Missouri, because he is the top mold expert in my state. He is an old, grumpy, very independent Air Force retiree, but knows his stuff. He can find things behind a microscope that just amazes me, such as he can tell the difference between an outside mold spore and an inside mold spore on certain species (Clad, Asp/Pen). He is the one who field trained me after I got all my training in, that is why I know so much about mold. If you are needing 24 hour turnaround though, you better call him first because he still works out in the field a lot. There was a few times he missed his 24 hour turn around, but it happens. I try not to guarantee 24 hour turnarounds any more, just in case he does not get it done in time, or FEDEX or UPS looses the samples. FEDEX and UPS has lost more of my samples in the last several years than him not getting them done in time. I do a lot of mold though. He does analyze samples on Saturdays and Sundays, so far for me at no extra charge.
After you send him some samples, he will send you back supplies for free. His contact info is jim@moldboy.com or 1-(417) 823-7427. You need to tell him I sent you if you leave a message, or he might not reply back. He stays very busy.
Thanks for all the feedback. The only problem here is that there was no balcony or any other area to do an outside test properly thats why I posted it. If it was a home I would have had some different options. The reason I have been using Pro Lab is that they seem to be the most reliable lab after talking to other IAC2 certified inspectors in my area. There is a local lab but they are so expensive and don’t have a proven track record around here. I will take any advice I can as I never stop learning and I always like to hear how other guys are doing their inspections so thanks again.
You can take your air sample ground level away from the building at least 20 feet and your outside air will be basically the same. The most of the time when the outside air is different, it is not due to the air being different, it is how the outside sample is taken. After more education and experience, you will understand this better. Mold is not an easy subject to understand because of multiple variables that are involved.
Truer words have not been spoken.
But at least they will tell him if there is a mold problem or not. 
One thing about Prolab, if you send them a blank cassette, sometimes they will still see mold. Sad but true.