Practical QC
Practical QC consists of four computer programs that are an integral part of Dr. L. H. Keith's American Chemical Society short course "Practical Environmental Sampling and Analysis". They are:
1. EPA's Data Quality Objective
(DQO) Training Software
2. Practical QC Control Samples
3. Practical GC Detector Selection, and
4. DQO-PRO which you can download free.
Each of these programs are menu driven and very easy to use. They are helpful as training tools and as computer programs that can be used by QA staff and chemists to check that the right kinds of QC samples and detectors are used to meet their DQOs. They are especially useful for project directors, engineers, regulators, lawyers and others who must work with and depend on environmental chemists for critical analytical data.
EPA's Data Quality Objective (DQO) Training Software consists of a
representative example that takes the user through a complete evaluation of a sampling and analysis project.
It is a user-interactive program that first presents all of the information needed to make decisions on how to sample and analyze groundwater samples, only some of which may be contaminated, and then allows the user to explore different methods of sampling and analysis to meet DQOs within budget and confidence level constraints.
Practical Q C Samples is an expert system that provides answers, explanations, and definitions for selecting QC samples needed to meet individual DQOs. It covers 15 types of QC samples:
- QC Check Samples
- Matrix Spikes
- Matrix Spike Duplicates
- Instrument Blanks
- Solvent/Reagent Blanks
- Glassware Blanks
- Field Blanks
- Trip Blanks
- Material Blanks
- Equipment Blanks
- Field Matrix Spikes
- Local Control Site Background Samples
- Area Control Site Background Samples
- Replicate Analyses, and
- Replicate Samples.
It is designed to help save time and money by eliminating QC samples not needed for a specific project and by making sure all the necessary QC samples needed
are used. Additionally, if QC data has already been obtained you can tell the program the kinds QC samples that were taken and it then advises you what kinds of Quality
Control information they can be used for and, just as importantly, what they cannot be used for.
Practical GC Detector Selection is an expert system that helps the user select the best detector(s) for analysis of environmental pollutants based on needs for selectivity and sensitivity and the types of compounds which will be analyzed. GC detectors considered include:
- mass spectrometers (full scan and selected ion monitoring),
- electron capture
- electrolytic conductivity
- nitrogen/phosphorus
- flame photometric
- flame ionization, and
- photoionization.
The advantages of each detector are presented along with recommendations for which detectors to use based on confidence level, sensitivity, selectivity and pollutant
types.
Practical QC Publication Date: 1993; revised 1996;
Requirements: 3 1/2 inch HD drive, 1.5 MB hard drive space, DOS 3.0 or higher, and Windows 3.1 or higher for DQO-PRO. Although Practical QC is a DOS-based program, you may also start it from Windows by using an automatic installation program which installs a Practical QC icon.
Regular Cost: $99.00
SPECIAL INTERNET DOWNLOAD OFFER $49.00
DQO-PRO (free software)
DQO-PRO is a $15,000 sample calculation program that can be downloaded free. It helps to calculate how many environmental and QC samples are needed to analyze for your specific objectives (e.g., a limit of 5% false positives or false negatives with a 95% confidence level or the number of samples needed for various methods based on standard deviations or relative standard deviations of the sampling and analysis measurement systems used). It also helps calculate how many samples are needed for systematic sampling for hot spots using various grids (triangles, squares, rectangles), hot spot shapes (circular or elliptical) and the probability of missing a hot spot if it exists.
“DQO-PRO” is a series of programs with a user interface like a common calculator and it is accessed using Microsoft Windows. DQO-PRO provides answers for three objectives:
- Determining the rate at which an event occurs,
- Determining an estimate of an average within a tolerable error, and
- Determining the sampling grid necessary to detect “hot spots”.
DQO-PRO facilitates understanding the significance of DQOs by showing the relationships between numbers of samples and DQO parameters such as (1) confidence levels versus numbers of false positive or negative conclusions; (2) tolerable error versus analyte concentration, standard deviation, etc., and (3) confidence levels versus sampling area grid size. The user has only to type in his or her requirements and the calculator instantly provides the answers.
You can download FREE DQO-PRO here
from a link Dr. Keith has provided through the American Chemical Society Division of Environmental Chemistry home page. He is also the editor of that home page.
Last Updated on January 16, 2001 - - - Number of visitors:
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