The Niton XLi 700 Series (XLi) XRF Services x-ray fluorescence (XRF) analyzer was demonstrated under the U.S. Environmental Protection Agency (EPA) Superfund Innovative Technology Evaluation (SITE) Program. The field portion of the demonstration was conducted in January 2005 at the Kennedy Athletic, Recreational and Social Park (KARS) at Kennedy Space Center on Merritt Island, Florida. The demonstration was designed to collect reliable performance and cost data for the XLi analyzer and seven other commercially available XRF instruments for measuring trace elements in soil and sediment. The performance and cost data were evaluated to document the relative performance of each XRF instrument.
This innovative technology verification report
describes the objectives and the results of that evaluation and
serves to verify the performance and cost of the XLi analyzer.
Separate reports have been prepared for the other XRF instruments
that were evaluated as part of the demonstration.
The objectives of the evaluation included determining each XRF instrument’s accuracy, precision, sample throughput, and tendency for matrix effects. To fulfill these objectives, the field demonstration incorporated the analysis of 326 prepared samples of soil and sediment that contained 13 target elements.
The prepared samples included blends of environmental samples from nine different sample collection sites as well as spiked samples with certified element concentrations. Accuracy was assessed by comparing the XRF instrument’s results with data generated by a fixed laboratory (the reference laboratory). The reference laboratory performed element analysis using acid digestion and inductively coupled plasma – atomic emission spectrometry (ICP-AES), in accordance with EPA Method 3050B/6010B, and using cold vapor atomic absorption (CVAA) spectroscopy for mercury only, in accordance with EPA Method 7471A.
The Niton XLi portable analyzer features a choice of either a full suite of traditional isotope (the XLi) or a miniaturized x-ray tube (the XLt which was evaluated in a separate report) for rapid chemical characterization of soils, sediment, and other thick homogeneous samples. The pre-set factory calibration allows simultaneous analysis of up to 25 elements, including all eight Resource Conservation and Recovery Act (RCRA) metals, in bulk materials with no requirement for site-specific calibrations or standards. Whether testing is performed in situ (directly onto the ground) or ex situ (bagged or prepared samples), sophisticated software automatically compensates for matrix variations from sample to sample, allowing the operator to simply “point and shoot” any bulk sample without unnecessary data entry or additional calibrations capability is also available.
Niton’s XLi 700 Series analyzers are easy to operate, light weight, ergonomic, and are an advanced isotope-based environmental XRF instrument. Niton offers various isotope options to best optimize performance for the environmental application.
This report describes the results of the evaluation of the XLi analyzer based on the data obtained during the demonstration. The method detection limits, accuracy, and precision of the instrument for each of the 13 target analytes are presented and discussed. The cost of element analysis using the XLi analyzer is compiled and compared to both fixed laboratory costs and average XRF instrument costs.