How would you measure the amount of atmospheric dust in a server room?
Solution 1:
Sounds like some push back from the vendor, but either way we used to have Air Particulate Meters in an old pharma company I worked for. They basically will measure everything in the air and tell you what's there. Dust is technically many different particles from various sources so you have to know what the individual makeup of the air is.
Unfortunately the testing devices are not cheap and range from expensive to ridiculous. If it's a big problem ask the vendor to bring one, sounds like they have had the problem before!
Either way I can't remember the brand we used but these look familiar: http://www.wolfsense.com/particle-counter-detector.html
Here's one on Amazon for a decent price, not sure how accurate but I don't think you need it to be real detailed: http://www.amazon.com/Dylos-DC1100-Laser-Quality-Monitor/dp/B000XG8XCI/ref=sr_1_2?ie=UTF8&qid=1341241387&sr=8-2&keywords=particle+counter
Solution 2:
You could go with a standard APC NetBotz solution. They've added external particulate sensors to the sensor suite. This would give you thresholding, SNMP and alert capabilities versus some of the handheld real-time units.