Field and Laboratory Measurements Related to Occupational and Consumer Exposures - Safety of Nanomaterials along Their Lifecycle - page 284

TABLE 13.1 ( continued )
Recent Publications on Point Source or Fugitive Emission (Source Domain 1)

Synthesis
Process Reference Nanomaterial Characterization Metric Summary/Conclusions

Wang et al.
(2012)

Hot-wall SiO 2 SEM PNC, PSD

(15-750 nm),
PSAC

Emission of silicon nanoparticles was not detected during the
processes of synthesis, collection, and bagging. This was attributed
to the completely closed production system and other safety
measures against particle release. Emission of silicon nanoparticles
signiicantly above the detection limit was only observed during the
cleaning process when the production system was open and
manually cleaned

Walser et al.
(2012)

Flame spray
pyrolysis

CaCO 3 No PNC Three scenarios of equipment failure were simulated during gas phase

production of nanoparticles in a laboratory. While under normal
production conditions, no elevated NOAA concentrations were
observed, worst case scenarios led to homogeneous indoor NOAA
concentrations of up to 10 6 #/cm 3 in the production room after only
60 s. The fast dispersal in the room was followed by an exponential
decrease in number concentration after the emission event.
The worst case emission rate at the production zone was also
estimated at 2 × 10 13 #/s with a stoichiometric calculation based on
the precursor input, density, and particle size. NOAA intake fractions
were 3.8-5.1 × 10 −4 #/cm³ inhaled NOAA per produced NOAA in
the investigated setting