Lub luag haujlwm tseem ceeb ntawm lub npog ntsej muag yog los tiv thaiv cov pa roj carbon monoxans, hmoov av, kab mob, lom thiab phom sij. Nws yog dav siv nyob rau hauv lub teb roj av, kev lag luam tshuaj, hlau kev tiv thaiv, kev tiv thaiv kev ua haujlwm ntawm cov nroog uas muaj mob hnyav thiab photochemical smog.
Cov hom npog cov ntsej muag muaj xws li cov qhov ncauj qhov ntswg thiab ib nrab ntawm lub ntsej muag, thiab tag nrho cov qhov ncauj qhov ntswg tau muab faib ua cov khoom siv siab thiab tsis zoo. Ib qho ntxiv, cov ncauj qhov ntswg kuj tseem tuaj yeem muab faib ua ib hom lim thiab hom kev cais raws li txoj kev uas lawv tau siv. The filtering gas mask consists of a mask and a gas filter canister (or filter element), and the gas filter canister is used to purify the contaminated air; Daim npog sab nrauv cov pa xa pa tawm los ntawm lub npog ntsej muag nws tus kheej, uas yog tsim nyog rau siab huab cua lossis oxygen {{} {tsis muaj ib puag ncig.
Cov txheej txheem ntawm kev siv daim npog roj teeb yog kom nkag mus rau hauv lub npog ntsej muag los ntawm kev nqus pa valve. Lub Airflow yog coj mus rau tus neeg ua pa ntawm lub qhov ncauj thiab lub ntsej muag npog lossis dej - thaiv daim npog ntsej muag. Thaum ua pa tawm, cov tshuaj tso pa tawm los ntawm tib neeg lub cev raug rho tawm rau hauv cov cua los ntawm kev ua pa tawm valve ntawm lub npog ntsej muag. Qhov no ua pa lub voj voog yog rov qab ua ntxiv mus kom txog thaum nws nres.
