hand holding magnifier glass with pm 2.5 indicator rating among pollution factor icon for particulate matter 2.5 micron of air

air bad breath breathe carbon dioxide clean concentration control detector dirty dust ecological emission environment factory filter forest good health hygiene index living manufacturing matter measure measurement monitor monitoring nature outdoors particulate pollution poor protection pure purify quality scale security smart smog smoke standard tech unhealthy weather hand holding magnifier glass indicator rating factor icon micron effect lifestyle concept 2 5 concept