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Aerosols
Colloids with a gaseous dispersing phase and either liquid (fog) or solid (smoke) dispersed phase; used in fumigation or in inhalation therapy; may contain propellant agents.
Year introduced: was in Cat D & J 1973-1982, was in Cat D only 1963-1972
Respiratory Aerosols and Droplets
Physiological aerosols and droplets expelled during coughing, sneezing, speaking and exhalation. Depending on the size, aerodynamic distribution or concentration they may play a role in transmission of infectious respiratory diseases.
Year introduced: 2022
Chlorofluorocarbons, Methane
A group of methane-based halogenated hydrocarbons containing one or more fluorine and chlorine atoms.
Year introduced: 2001(1973)