Exposure to Nanoparticles - Environmental and Human Health Impacts of Nanotechnology - page 328

Metric Devices Notes

Number Condensation

Particle Counter
(CPC)

Real-time particle number concentration measurements
between 10 nm and 1 m.

> µ

Scanning Mobility
Particle Sizer
(SMPS)

Real-time (mobility diameter) measurement of aerosol
size distribution - interpreted as number
concentration.

Electrical Low
Pressure
Impactor (ELPI)

Real-time size selective (aerodynamic diameter) measure-
ment of size distribution. Size selected samples may be
further analysed off-line.

Optical Particle
Counter (OPC)

Real-time number concentration measurement of
particles larger than 300 nm in diameter. When used

with a CPC, OPCs may offer insight into the number
concentration of particles smaller than

∼

∼ 300 nm.

Electron
Microscopy

Off-line analysis of aerosol number concentration (and
other parameters).

Mass Size selective

personal sampler

Off-line gravimetric or chemical analysis of fi lter or
impactor samples. Some cascade impactors have lower
stages which sample particles < 100 nm.

Size selective static
sampler

Off-line gravimetric or chemical analysis of fi lter or
impactor samples. Some cascade impactors have lower
stages which sample particles < 100 nm aerodynamic

diameter.

Tapered Element
Oscillating
Microbalance
(TEOM)

Sensitive real-time monitors such as the TEOM may be
useable to measure nanoaerosol mass concentration
on-line, with a suitable size selector inlet.

Scanning Mobility
Particle Sizer
(SMPS)

Real-time (mobility diameter) measurement of aerosol
size distribution. Data may be interpreted in terms of
aerosol mass concentration, only if particle shape and
density are known.

Electrical Low
Pressure
Impactor (ELPI)

Real-time size selective (aerodynamic diameter) measure-
ment of size distribution. Data may be interpreted in
terms of mass concentration if particle charge and
density are known. Size selected samples may be
further analysed off-line.

Specifi c
surface
area

Scanning Mobility
Particle Sizer
(SMPS)

Real-time (mobility diameter) measurement of size
distribution - interpreted as specifi c specifi c surface
area concentration (Rogak et al. , 1993).

Electrical Low
Pressure
Impactor (ELPI)

Real-time size selective (aerodynamic diameter) measure-
ment of active specifi c specifi c surface area. Size
selected samples may be further analysed off-line.

SMPS and ELPI
used in parallel

Differences in measured aerodynamic and mobility
diameter can be further used to estimate surface area.

Diffusion Charger Real-time measurement of aerosol active surface area.

Active specifi c surface area scales as particle diameter
squared below 100 nm, and particle diameter to the

∼

power 1 above m. Some commercial devices tailor

the response to particle specifi c surface area depositing
in selected regions of the lungs.

1

∼ µ

Electron
Microscopy

Off-line analysis of aerosol specifi c surface area concen-
tration (and other parameters). Specifi c surface area is
derived form a two-dimensional projection when using
transmission electron microscopy.