Particle counters are used to test air quality. I found an inexpensive one that is ideal for your workshop. I started a thread about it at woodnet and sawmillcreek, and the response was pretty enthusiastic. This led to me negotiating a group purchase of the units, where we will get an additional 35% off.
Here is the woodnet thread:
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is the sawmillcreek thread:
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you want one of these, this is the order form you have to download, fill out, and fax to Dylos:
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