Cov pa dej me me uas muaj siab siab tuaj yeem tswj tau hluav taws, tiv thaiv hluav taws thiab tua hluav taws raws li peb yam kev cuam tshuam ntawm kev txias, kev ua pa tsis taus thiab kev rwb thaiv tsev. Nws yog cov thev naus laus zis zoo tshaj plaws los hloov cov tshuaj tsuag dej ib txwm muaj, cov pa dej nruab nrab thiab qis, roj, aerosol, hmoov qhuav, ua npuas dej thiab lwm yam kev tua hluav taws.