The Model 3070A Electrical
Aerosol Detector (EAD) is a novel
particle instrument that complements
TSI’s family of Condensation
Particle Counters (CPCs).
It is a robust, low-cost, easy-to-use
instrument that operates continuously
and provides very fast measurements.
Like a CPC, the EAD
measures particle concentration as
a function of time. It differs in
that it measures a parameter called aerosol
diameter concentration, a property of ultrafine
aerosol particles that is promising for correlating
with their adverse health effects.
The EAD is a unique instrument that offers
a number of exciting features:
• Submicrometer particle measurements – in
the range from 10 nanometers to greater than
1 micrometer
• High time resolution – maximum data rate of
3.75 readings per second allows the EAD to
detect fast-changing events and study aerosol
dynamics
• Mean diameter of aerosol (when combined with
a CPC) – calculated using the diameter concentration
measured by the EAD divided by the
number concentration from the CPC
DMean = (EADdiameter/CPCnumber)
of concentration range (0.01 to 2500 mm/cm3)
without the need for coincidence correction or
aerosol dilution
• Robustness and ease-of-use – both characteristics
are critical for continuous, routine
measurements
• No working fluid – allows easy transport and
eliminates the need to drain a reservoir
• No consumables – translates to a low cost of
operation
• Unmatched reproducibility – readings of two
co-located EADs during a six-month field trial
were within ±1 percent (see figure on next page)