The ETS –V1 target is Environmental Tobacco, its design has a four stage air purification system: Air first enters the disposable pleated pre-filter, which removes coarse dust, lint and fibers, while also prolonging the life of the other particulate filters. Afterwards the air enters the v-bag filter capturing the finer dust particles as small as 0.3 microns. Then the air flows to the gas filter where the gas contaminants are adsorbed. The final filter is a high efficiency HEPA 11 with integral efficiency above 95%.
A lit cigarette gives off 4,700 chemical compounds, some in form of aerosol (solid and liquid) some in form of gas.
There are 20 constituents of particulate matter and 17 gas phase components in ETS with known adverse health effects.