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Guide for Characterization of Sites Contaminated with Energetic Materials
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The results from the test kits are determined with the DTECHTOR environ-
mental field test meter (EM Science). This device, a hand-held reflectometer
powered by a 9-V plug-in battery, measures the amount of light reflected from
the surfaces of the color-developed test and reference sides of the cup assembly.
Readings are given in percentages and are then translated into TNT- or RDX-
equivalent concentrations. This procedure is well documented in the field test kit
package.
Advantages and Limitations of EIA Field Screening
The EIA field screening method is excellent for use as a positive/negative
field test to discriminate between which samples are to be sent to the laboratory
for extraction and analysis and for discriminating between high and low levels of
contamination. However, the requirement for multiple tests per sample, particu-
larly for highly concentrated explosives, increases the amount of manipulations
and cost per sample. Moreover, the use of a reference test and the reflectometer
also represent a limitation since the operator must be very attentive in order to
take an accurate reading at the correct time. Erroneous results can easily be
obtained if all procedures are not followed carefully. However, this technique
does have the advantage of being easy to perform in the field, requiring minimal
space to operate. Lastly, the method was designed only for RDX and TNT;
therefore, the EIA field testing methods are more selective than the colorimetric
methods covered in Appendix H.
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