I had a Radio Shack meter and it worked pretty well. I did some sampling and then had an Industrial Hygienist come in and my cheap meter was dead on to his more expensive model. So, it should work for what you need, but I would be careful using it for a hearing protection program.
A major source of objection to a free economy is precisely that it ... gives people what they want instead of what a particular group thinks they ought to want. Underlying most arguments against the free market is a lack of belief in freedom itself.
- Milton Friedman