lhh2k
This question appears overly broad to me. Before you decide what type of filters you need, you need to define what your requirements are. You need to consider what exactly is the "dust, gas, acetone" makeup that needs to be filtered. There is a lot of difference if the "dust" is ordinary dirt or if it includes grinding products from a toxic metal. Similarly, what type of gas?
You also need to determine how often people will be in the environment. If people are present all the time, then you have different needs then if people only go in once a month (maybe use air masks) or if you can purge the environment before they go in.
Finally, you need to determine the applicable regulations for your locality given the above. In the US, for example, the Environmental Protection Agency has a considerable interest in what is released to the environment.
Patricia Lougheed
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