Light absorption measurement at 880 nm interpreted asBlack Carbon (‘BC’, also called ‘Elemental Carbon – EC’).
Measurement at 370 nm designated as ‘UVPM’, interpreted
as a ‘Brown Carbon’ (‘BrC’) indicator of aromatic organic compounds such as are found in smoke from biomass burning.
Attenuation ( 100 * ln[I0/I] ) in ‘ATN units’ at two wavelengths.
No other aerosol species absorbs light even 0.001 times as
much as Black Carbon in the visible range.
Light absorption measurements can be converted to BC or
1 ATN unit, equivalent to 0.06 μg/cm² BC on filter. If collected on a 47mm diameter filter at a 16.7 LPM flow rate for 24 hours, this represents a Limit Of Detection for BC of 0.075 μg/m³.
Maximum loading of 125 ATN units is optimal, equivalent to an
average BC concentration of 3.1 μg/m³ collected on a 47 mm diameter filter at 16.7 LPM for 24 hours. At higher ATN values , the linearity may be impaired. The Data Reduction Template suggests other choices of filter collection area, sampling flow rate and sample collection time to permit accurate data over a very wide range of BC concentrations.
Quartz fiber, T60 Teflon coated borosilicate glass fiber, or Teflon membrane filters may be analyzed. For the use of other
substrates contact Magee Scientific.
SAMPLE ANALYSIS AREA
Accommodates 25 mm, 37 mm, and 47 mm diameter filter
NIST‐traceable neutral density filter kit option available.
Digital data available via rear RS‐232 (COM) and USB ports.
DISPLAY AND INTERFACE
2‐line display screen with keypad.