The atomization of molten materials produces a large amount of dust and fumes made up of very fine particles (ca. 80–95% of the particles by number <100 nm). Proper extraction facilities are vital not only for personal safety, but to minimize entrapment of re-frozen particles in the sprayed coatings. The use of respirators fitted with suitable filters is strongly recommended where equipment cannot be isolated.
Certain materials offer specific known hazards:. The Toxicity from thermal spray aerosols is dependent on the metal profile of the thermal spray. 
#Finely divided metal particles are potentially pyrophoric and harmful when accumulated in the body.
#Certain materials e.g. aluminum, zinc and other base metals may react with water to evolve hydrogen. This is potentially explosive and special precautions are necessary in fume extraction equipment.
#Fumes of certain materials, notably zinc and copper alloys, have a disagreeable odour and may cause a fever-type reaction in certain individuals (known as metal fume fever). This may occur some time after spraying and usually subsides rapidly. If it does not, medical advice must be sought.
#Fumes of reactive compounds can dissociate and create harmful gasses. Respirators should be worn in these areas and gas meters should be used to monitor the air before respirators are removed.