Page 11 - Performance Verification Statement for the Chelsea UV Aquatracka Fluorometer

Ref. No. [UMCES]CBL 2013-014
ACT VS12-01
RESULTS of LABORATORY TEST
Laboratory tests of response factor, precision, range, and reliability were conducted at
Moss Landing Marine Lab utilizing five different challenge compounds covering a range of
fluorescent properties (see Table 1 above) to facilitate comparisons against the range of optical
detection windows utilized by participating hydrocarbon sensors. Tests were performed in
insulated 500 L, black acrylic tanks in a dark room using filtered deionized water (DI) as the
background medium (Photo 1). Reference samples of these challenge compounds were
characterized and quantified using EEMS on a FluorMax-2 (photo 2) over a range of
concentrations from 1 – 1000 ppb.
Photo 1. Instrument Rack and tank. Photo 2. EEM’s Generation
EEM fluorescence maps of each of the five challenge compounds, dosed at a
concentration of 50 ppb, are presented along with the region of the optical window of the
Aquatracka UV-CDOM (Figure 1) and Aquatracka UV-Hydrocarbon (Figure 2) filter sets.
Excitation and Emission maximums of the challenge compounds varied by over 100 nm, with
Quinine Sulfate mapping most closely with the optical window UV-CDOM filter set and
Carbazole mapping most closely with the optical window of the UV-HC filter set. The response
curves for the UV-CDOM (tested against NSDA, QS, Carbazole, and BB3) and UV-HC (tested
against #2 Diesel fuel) measurements tested at concentrations ranging from 1 – 1000 ppb are
shown in Figure 3. Results show instrument response (in mV) presented against both
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