xvEPA
United States Environmental Monitoring and Support EPA-600 7-79-136
Environmental Protection Laboratory June 1979
Agency Research Triangle Park NC 27711
Research and Development __^_
Quality Assurance in
Support of Energy
Related Monitoring
Activities
Annual Report No. 2
Interagency
Energy/Environment
R&D Program Report
-------
RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the INTERAGENCY ENERGY-ENVIRONMENT
RESEARCH AND DEVELOPMENT series. Reports m this series result from tne
effort funded under the 17-agency Federal Energy/Environment Research and
Development Program. These studies relate to EPA's mission to protect the pub';c
health and welfare from adverse effects of pollutants associated with energy s>:-
tems. The goal of the Program is to assure the rapid development of domest.-;
energy supplies in an environmentally-compatible manner by providing the nec-
essary environmental data and control technology. Investigations include analy-
ses of the transport of energy-related pollutants and their health and ecological
effects; assessments of, and development of, control technologies for energy
systems; and integrated assessments of a wide'range of energy-related environ-
mental issues.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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QUALITY ASSURANCE IN SUPPORT OF ENERGY
RELATED MONITORING ACTIVITIES
Annual Report No. 2
by
Mark Cher
Rockwell International
Environmental & Energy Systems Division
Environmental Monitoring & Services Center
Newbury Park, California 91320
Contract No. 68-02-2412
Project Officer
Steven M. Bromberg
Quality Assurance Branch
Environmental Monitoring and Support Laboratory
Research Triangle Park, North Carolina 27711
ENVIRONMENTAL MONITORING AND SUPPORT LABORATORY
U.S. ENVIRONMENTAL PROTECTION AGENCY
RESEARCH TRIANGLE PARK, NORTH CAROLINA 27711
-------
DISCLAIMER
This report has been reviewed by the Environment Monitoring and Support
Laboratory, U.S. Environmental Protection Agency, and approved for publica-
tion. Mention of trade names or commercial products does not constitute
endorsement or recommendation for use.
-------
ABSTRACT
This report describes and summarizes the activities and achievements
of Rockwell International's Environmental Monitoring & Services Center (EMSC)
during the second year of the program entitled, Quality Assurance in Support
of Energy Related Monitoring Activities. The activities cover generally the
period from September 1977 to September 1978.
The purpose of the program is to establish a quality assurance data base
for ambient air monitoring in specified geographical areas around present and
proposed energy development projects, and to provide technical assistance to
enable existing monitoring networks to achieve a high level of data quality.
A goal of the program is to enable the government to utilize and compare air
monitoring data from diverse sources for future study and planning purposes
by providing information concerning data quality from the Individual monitor-
ing networks.
A major change in the program occurred in September 1978, when the number
of participants was greatly expanded to include laboratories and sites located
in the Ohio and Tennessee Valleys, and also in several eastern states in
Region III. An initial Quality System Audit of the new participants has been
started, and detailed evaluation reports containing 11st of recommendations for
eliminating observed deficiencies will be submitted to EPA.
Regularly scheduled Quality Control Reference Sample Audits are being
continued for the analysis of sulfate, nitrate, S02, N02> and CO, and for weight
measurement and high volume flow rate. In these surveys reference samples or
devices are submitted to participating laboratories and their results are
111
-------
compared with those obtained by Rockwell. Performance results for the first
two years of the program have remained essentially constant for sulfate,
nitrate, SO-, and CO. The results for CO are noteworthy for their consis-
tently high quality. Results for N02 have shown significant improvement, and
in the last three surveys in 1978 the level of agreement between the labora-
tories and Rockwell has been generally very high. Improvements in performance
have also been observed 1n the weighing and high volume surveys.
An inter!aboratory comparison study involving Rockwell and another laboratory
to determine the causes for the large differences in the analysis of metals in TSP
samples which had been observed at the beginning of the program was completed in
1978. The differences were determined to be caused primarily by differences in
extraction procedures. The laboratory has adopted the same procedure used by
Rockwell, and subsequent analyses have shown major improvement in the level of
agreement obtained in the analysis of copper, iron and manganese.
Quarterly Calibration System Audits are being continued at specified moni-
toring sites. Known concentrations of pollutants are delivered to each continuous
analyzer, and the observed response is compared with that predicted by the agency's
calibration. Procedures have been developed to assure reliable performance
by the audit devices and standards. Additional checks on the equipment and
procedures are made by means of quarterly audits performed In the EPA/EMSL
laboratory at Research Triangle Park, North Carolina.
Approximately 150 Calibration System Audits have been completed thus far,
and audit reports have been submitted to EPA. Evaluation procedures for reporting
on individual and collective performance have undergone several changes during
the past year. A major achievement of the program has been the remarkable
IV
-------
Improvement in the calibration accuracy observed for several pollutants,
especially NO, NO , and N0?. Some problems with regard to the calibration
rt b
of ozone analyzers are still evident.
Technical assistance has been provided to participating agencies, as
requested by the Project Officer. Much of the assistance is given informally
during site visits. Assistance was also provided concerning specific labor-
atory and calibration problems during special visits by Rockwell personnel to
the participating agencies. A brief description of these and other types of
technical assistance is given in the report.
This report was submitted in fulfillment of Contract No. 68-02-2412 by
Rockwell International Environmental Monitoring & Services Center under the
sponsorship of the U.S. Environmental Protection Agency. Work under this
contract is scheduled to continue in the west until July 13, 1981, and in
the east until September 13, 1983.
-------
CONTENTS
Disclaimer 11
Abstract 111
1. Introduction 1
2. Quality System Audits 4
3. Quality Control Reference Sample Audits 7
Sulfate/N1trate Analysis 12
S02 Analysis 20
N02 Analysis 25
CO Analysis 29
Weighing Survey 32
High Volume Flow Rate Measurement 32
Interlaboratory Comparison Study of Metal Samples 37
4. Calibration System Audits 44
5. Technical Assistance 54
6. Plans For Next Year . . . 57
References 59
vi
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SECTION 1
INTRODUCTION
This report describes and summarizes the activities and achievements of
Rockwell International Environmental Monitoring & Services Center during the
second year of the Contract No. 68-02-2412, entitled Quality Assurance in
Support of Energy Related Monitoring Activities. The effective date of the
contract was July 13, 1976, and the program is scheduled to be completed on
July 13, 1981.
On March 24, 1977, the contract was enlarged to include additional Quality
System Audits and Calibration System Audits of sites located in Colorado, Utah,
and Montana. On August 9, 1977, the contract was further expanded to include
Quality System Audits of seven water quality field stations of the U.S. Geological
Survey in the states of Arizona, Colorado, Montana, New Mexico, North Dakota, Utah,
and Wyoming.
A major modification to the contract was put into effect September 13, 1978,
when the program was expanded to include laboratories and sites located in the
Ohio and Tennessee Valleys, and also in several eastern states in Region III.
At the time of the modification, the work for Region VIII, which was initiated
on March 24, 1977, as described above, was extended for an additional 12 months.
The activities described in this report cover generally the period from
September 1977 to September 1978. For convenience, we refer to the Western
Q.A. Program and the Eastern Q.A. Program to describe the work according to
the geographical location of the participating groups. The Eastern Q.A.
-------
Program includes groups in the Ohio and Tennessee Valleys, and in the Region
III states. In the period covered by this report, the overwhelming majority
of the work was performed with groups comprising the original Western Q.A.
Program.
The purpose of the Eastern and Western Quality Assurance Programs is to
develop and implement a quality assurance program for use by networks moni-
toring air quality around present and proposed energy development projects.
A goal of the program is to enable the government to utilize and compare air
monitoring data from diverse sources for future study and planning purposes
by providing information concerning data quality from the monitoring networks.
A secondary goal is to provide technical assistance to the participating groups
to help them achieve a high level of performance. In the west the energy
projects are located in the states of Montana, South Dakota, North Dakota,
Wyoming, Utah, Colorado, Arizona, Nevada, New Mexico, and California. In
the east the energy projects are located in the states of Kentucky, West
Virginia, Illinois, Ohio, Pennsylvania, and Indiana. Additional groups,
which are not necessarily involved in energy development projects, are «
located in Delaware, Maryland, Virginia, and the District of Columbia,
are also associated with the Eastern Q.A. Prorram.
This Annual Report is written as a general overview of performance and
>gress thus far. In order to keep this report within manageable size, the
der will oftentimes be directed to specific reports, submitted to EPA, should
ater detail be required.
-------
The Eastern and Western Quality Assurance Programs are divided into
four task areas involving:
1. Quality System Audits - an initial on-site review of
laboratories and field sites;
2. Quality Control Reference Sample Audits - a sample submissions
audit program to the laboratories;
3. Calibration System Audits - on-site field calibration audits;
and
4. Technical assistance to the laboratories, as required.
All the work carried out by Rockwell in connection with these tasks is
summarized in the following sections. Section 2 describes the Quality System
Audits, Section 3 discusses the results of the Quality Control Reference Sample
Audits and an interlaboratory comparison study; Section 4 summarizes Calibration
System Audit results; Section 5 describes technical assistance given to the
various agencies; and Section 6 outlines the plans for next year.
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SECTION 2
QUALITY SYSTEM AUDITS
All Quality System Audits in the Western Q.A. Program were completed during
the first year of the contract and are described in the first annual report.
Table 1 lists the groups scheduled to be evaluated for the Eastern Q.A.
Program. The 11st includes all the groups who have agreed to participate as
of December 1978. Additional groups have been contacted by EPA and they will
be added to the list if the necessary approvals can be secured.
Preliminary meetings with some of the eastern participants were held in
Alexandria, Philadelphia, and Chicago in June and in August 1978. The Project
Officer, the Program Manager, and the EPA Q.A. Coordinators for Regions III
and V were 1n attendance at these meetings, which were held for the purpose
of informing the participants about the goals, organization, mechanics, and
schedules of the Eastern Q.A. Program.
As with the Western Q.A. agencies, all the groups in Table 1 will be
visited, and the laboratories and field sites will be evaluated by Rockwell
personnel. The same questionnaires used previously in the west were mailed
to the eastern groups prior to the Rockwell visit in order to expedite the
evaluation interview. The first four groups in TaLle 1 were visited by the
Program Manager in August 1978. The rest of the groups win be visited at a
later time.
A detailed report covering the Quality System Audits will be made for
each group, and each group will be given the opportunity to comment upon the
orellminary draft of the report. When appropriate, these comments will be
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TABLE 1. LIST OF AIR MONITORING GROUPS PARTICIPATING
IN EASTERN .QA PROGRAM
Group
Headquarters
Air Monitoring Site
Locations to be
Audited
District of Columbia
State of Virginia
Fairfax County
City of Alexandria
State of Maryland
County of Baltimore
City of Baltimore
State of Delaware
State of Pennsylvania
City of Philadelphia
Allegheny County
State of West Virginia
Ohio Edison
Pennsylvania Electric
State of Indiana
City of Cincinnati
Regional Air Pollution
Control Agency
Washington, DC
Richmond, VA
Fairfax, VA
Alexandria, VA
Baltimore, MD
Baltimore, MD
Baltimore, MD
Wilmington, DE
Harrisburg, PA
Philadelphia, PA
Pittsburgh, PA
Charleston, WV
Akron, OH
Johnstown, PA
Indianapolis, IN
Cincinnati, OH
Dayton, OH
Washington, DC*
Richmond* Norfolk*
Hampton*
McLean*
Alexandria*
Baltimore* Washington*
DC (Maryland suburbs)*
Baltimore*
Baltimore*
Wilmington*
Various locations
in state
Philadelphia
Pittsburgh
Charleston, Wheeling
Southern Ohio
Indiana, PA
Southern Indiana
Cincinnati
Dayton
* These sites are not energy related but were added on to the program for
convenience.
-------
noted and used 1n preparing the final report, copies of which will be sent to
the EPA.
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SECTION 3
QUALITY CONTROL REFERENCE SAMPLE AUDITS
Regularly scheduled Quality Control Reference Sample Audits
have been carried out for the following analyses or measurements;
1. Sulfate/Nitrate Analysis
2. S02 Analysis
3. N02 Analysis
4. CO Analysis
5. Weighing Performance
6. High Volume Flow Rate Measurement.
In addition to the laboratory surveys, an inter!aboratory comparison
study has been carried out with one laboratory in which approximately 75 filters
were analyzed by the laboratory and Rockwell for trace metals and the results
compared.
Table 2 lists all the surveys performed in the first two years of the
program by date. Participating laboratories in each survey are indicated by
a check (/) mark.
For the chemical analysis survey (1-4 in the above list), Rockwell
obtains from commercial vendors, either directly or through EPA, multiple
sets of the appropriate samples which are then submitted for analysis to
participating laboratories. Ten replicate samples are first analyzed at
Rockwell, and the mean value of the analyses is by definition the "true"
value with which the results of all the participants are compared.
To assure the correctness of the Rockwell "true" value, several internal
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TABLE 2. LIST OF INTERLABORATORY PERFORMANCE SURVEYS AND PARTICIPANTS
(*)
oo
Agency
Arizona State
Colorado State
Energy and
Environmental
Resource
Consultants
Lockheed
Montana State
New Mexico State
North Dakota
State
Northern Testing
Lab
Northrop Services
Inc.
South Dakota
State
Ute Research
Wyoming State
Yellowstone
County
Survey and Date by Quarter
SO/NO"
4^76 1£77 2£77 3^77 4/77 1/78 2/78
A
A A A A V
so
4/76 2/77 3/77 4/77 1/78 2/78 3/78
V6 2t77 3l
V
7*1A check (/) means that the agency participated in the survey.
(t) S04 only
(#) Summary data for these surveys in first annual report.
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TABLE 2 (Continued)
Agency
Albuquerque
Arizona State
C-a
C-b
Colorado State
Energy and Envi-
ronmental Re-
search consult-
ants
Lawrence Radia-
tion Labs
Montana State
Montana Power Co.
New Mexico State
No. Dakota State
Northern Testing
Lab
So. Dakota State
Ua/Ub
Ute Research
Utah State
Wyoming State
Yellowstone
County
Survey and Date by Quarter
N02
1/77 2/77 3/77 4/77 1/78 2/78 3/78
f # #
///////
///////
/ /
///////
///////
///////
/ / / / /
///////
///////
— ' -••' - • i '• - ••« - ' •• • ii •* i1 '"." "l—f
CO
4/76 1/77 3/77 4/77 1/78 2/78
III
//////
//////
/ / / / ^ /
/ / / / /
//////
//////
'
Weighing
1/77 1/78
#
^ /
• /
/ /
/ /
/ /
/ /
/ /
/ /
/ /
/ /
/ /
/ /
/ /
/ /
Hi-Vol
1/77 1/78
/ /
/ /
/ /
/ /
/
/
/ /
/ /
/ /
/ /
/ /
/ /
/ /
/ /
/ /
/ /
A check (V) means that the agency participated
(#) Summary data for these surveys in first annual report.
survey.
-------
and external quality control procedures are being used. Internal quality
control procedures in the Rockwell laboratory include comparison of analyses
of replicate samples, comparison of every new stock standard solution with
the old one, duplicate calibration curves before and after analysis, analysis
of quality control standards every 10 samples, and maintenance of routine
quality control charts on calibration parameters to establish laboratory
control limits. External quality control is provided by comparing the
Rockwell "true" value with the mean value obtained through replicate sample
analysis either by the QAB EMSL-RTP laboratory or by the vendor. This com-
parison is included in each report.
The evaluation of laboratory performance is done in several ways. The
most direct way is to compare the concentration determined by each laboratory
with the "true" value as determined by Rockwell. Linear graphs are prepared
in which the laboratory values are plotted against the "true" values. The
slope, intercept, and correlation coefficient for each laboratory line are
then tabulated as indices of performance. Perfect agreement between a
laboratory and Rockwell for all analyses results in a straight Tine with unit
slope, zero intercept, and a correlation coefficient equal to 1.0000.
The slope of the line is a good measure of overall analytical accuracy,
provided that the Intercept Is small compared to the concentrations being
analyzed. For example, If the Intercept 1s small, a slope of 1.05 Implies a
level of agreement with Rockwell of 51.
If the slope is near 1.0, a large Intercept Indicates a bias In the
analysis which might be caused by such errors as incorrect blank corrections
or contaminations in the water supply. The magnitude of the intercept must
10
-------
be evaluated by comparison with the sample size. For example, if the sample
3 3
size is 10 yg/m , an intercept of 1 ug/m represents a 10% bias.
A second method used for evaluating laboratory performance is to calcu-
late average percent differences between the laboratory analysis values and
the "true" values. The average percent differences as well as the standard
deviation of the individual percent differences are tabulated by laboratory
for each quarterly audit as measures of analytical error. The calculations
are explained in detail in the proposed EPA regulations which appeared in
the Federal Register in August 1978 as EPA 40 CFR Part 58, "Air Quality
...... .... i
Surveillance And Data Reporting;"Appendix A - Quality Assurance Requirements
for State and Local Air Monitoring Stations (SLAMS) (1). The major difference
between our procedure and that described in the Federal Register is that the
latter specifies 0.20 and 0.80 yg/ml for the concentration of the audit samples
for both S0£ and NOg, while in the current program the concentration of the audit
samples cover a much wider range. However, we understand that Appendix A is being
changed and the final regulations will be promulgated sometime in 1979. Another
difference from the EPA regulations is that our program includes audits of SO!
and N03 analysis, neither of which is required by the proposed regulations.
A third method used to evaluate laboratory performance is to determine
whether each laboratory analysis results falls within arbitrarily defined
concentration ranges denoted as "sample range" and "target range". The
"sample range" is intended to describe the variability in the analysis of
presumably identical samples within one laboratory but at various times and
under various conditions, i.e., "normal laboratory operation". The "target
range" is intended to bracket an acceptable range of variability among
different laboratories and is larger than the "sample range".
11
-------
Definitions of "sample range" and "target range" have not remained the
same throughout the program. For most of the surveys the "sample range" and
the "target range" are defined as R ± 3 a and R ± 5 a, respectively, where
R is the "true" value (i.e., the mean value of Rockwell's analyses) and o is
the standard deviation of Rockwell's replicate analyses. For CO the standard
deviation a is extremely small so that a more practical definition is required.
For CO the "sample range" and "target range" were defined at various times as
R ± r where r was either a constant ppm value (e.g., r » ± 0.5 ppm), or a
constant percent of R (e.g., r = ± 4%). Of course, the value of r was not
the same for the sample range and for the target range.
Because the definitions of range depend on the performance of the
Rockwell laboratory through the experimentally determined value of o, great
care should be exercised in evaluating performance by means of the range
criteria, particularly when comparing results from different surveys. The
"sample range" and "target range" criteria are most useful for comparing the
performance of different laboratories within the same survey. Because of
this limitation, no discussion will be given inthis report in terms of the
range criteria. The Interested reader should consult the individual Quality
Control Reference Sample Audit (Interlaboratory Performance Survey) reports
submitted to EPA.
Each type of survey will be discussed eaparately below.
Sulfate/Nitrate Analysis
The sulfate/nitrate performance survey requires participating labora-
tories to analyze a set of four to six filter strips spiked with varying
-------
amounts of sulfate and nitrate ions. At least 10 sets of filters presumed to
be identical to those analyzed by the laboratories are analyzed by the
Rockwell Chemistry Laboratory using the methyl thymol blue procedure for SO^
and the copperized cadmium reduction method for NOl. In the interpretation
of results no bias or adjustment is made for the fact that laboratories
included in the surveys use methods different from Rockwell. All laboratories
use EPA accepted methods which give presumably equivalent results, making such
adjustments unnecessary.
Tables 3 and 4, taken from the second quarter 1978 report, list average
percent difference d., standard deviation S.,, and the linear parameters
J J
associated with each laboratory for all surveys to date. The average percent
difference d. is obtained by first calculating the percent difference for each
J
individual sample using the equation
/Yi - xi \
d. = (-TT-1-; 100 (D
where Y. and X. are the concentrations determined by a laboratory and by
Rockwell, respectively. The value of d. is simply the average of all the
d.'s for each laboratory and S. is the standard deviation of the d.'s. To
i j «
preserve anonymity, the identities of the laboratories are not shown. (There
is no correlation between the identity codes in the tables of this report.
Thus Agency A in one table is not necessarily the same as Agency A in another
table.)
The composite data in Tables 3 and 4 were obtained by combining results
of all samples and all laboratories and are used to evaluate overall perfor-
mance. Figure 1 shows graphs of d. and d. ± S. for the composite data as a
J J J
13
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TABLE 3. SUMMARY OF AGENCY PERFORMANCE FOR S04 SURVEYS
Agency
Code
A
B
C
D
E
Quarter/
Year
2/77
3/77
4/77
1/78
2/78
1/77
2/77
3/77
4/77
1/78
2/78
4/76
1/77
2/77
3/77
4/77
1/78
2/78
4/76
1/77
2/77
3/77
4/77
1/78
2/78
Avg %
D1ff.
3d
7.3
6.8
5.4
4.9
12.5
2.5
10.7
3.2
-3.0
6.3
29.6
-16.2
5.9
-13.3
-18.7
-6.4
-23.6
6.1
-5.6
9.0
-0.5
-20.8
-2.9
-8.8
-3.4
Std.
Dev.
S1
4.5
3.5
5.8
15.5
7.2
7.9
9.7
3.2
4.7
7.8
74.2
18.0
3.7
9.5
36.5
10.1
59.1
4.2
21.4
5.0
12.6
31.1
15.9
22.3
9.9
SI ope
1.005
1.042
1.009
1.175
1.036
1.030
1.046
1.011
0.950
1.010
0.801
0.926
1.031
0.755
1.093
0.838
1.326
0.962
1.054
1.087
0.869
0.543
0.960
1.097
1.022
Intercept
yg/m3
0.333
0.194
0.843
-0.383
0.287
0.075
0.433
0.149
0.690
0.524
1.537
0.075
0.459
0.982
-0.758
1.355
-1.797
1.209
-0.012
0.147
0.556
0.735
-0.225
-0.529
-0.041
(continued)
14
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TABLE 3 (Continued)
Agency
Code
F
G
H
I
EPA/QAB
Quarter/
Year
4/76
1/77
2/77
3/77
Mil
1/78
2/78
4/76
1/77
2/77
3/77
4/77
1/78
2/78
4/76
1/77
2/77
3/77
4/77
1/78
2/78
1/78
2/78
4/76
1/77
2/77
Avg %
Diff.
^
34.7
12.6
-14.6
-19.0
-1.5
-6.5
38.2
** 119.2
12.3
** 131.6
3.9
0.6
-1.1
0.3
-9.3
-4.9
-25.9
9.9
3.8
-13.4
6.6
-1.9
-0.4
-0.1
3.3
-1.2
Std.
Dev.
Si
54.1
14.3
19.2
33.7
26.5
12.4
51.7
123.3
8.5
31.3
13.8
7.2
13.1
5.9
12.4
4.0
18.5
4.6
4.7
13.1
2.8
17.0
13.8
1.9
2.3
8.3
Slope
0.810
1.351
1.102
0.848
1.223
1.039
0.972
0.643
1.075
1.860
0.948
1.039
1.061
1.058
1.036
0.895
0.913
1.045
1.049
0.977
1.027
1.073
1.005
1.032
1.053
0.946
Intercept
ug/m
1.066
-2.973
-1.286
-0.301
-3.126
-0.340
1.393
4.191
0.875
2.272
0.886
-0.392
-0.055
-0.144
-0.194
0.718
-0.565
0.398
-0.205
-0.353
0.148
-0.133
0.122
-0.114
-0.190
0.290
** Laboratory data not used for computing
composite results.
(continued)
15
-------
TABLE 3 (Continued)
Agency
Code
EPA/QAB
(cont'd)
Composite
Quarter/
Year
3/77
1/78
2/78
4/76
1/77
2/77
3/77
4/77
1/78
2/78
Avg %
Diff.
*i
2.8
-2.9
6.1
0.7
5.9
-5.3
-4.0
-0.6
-5.5
10.8
Std.
Dev.
Si
3.7
15.1
3.9
32.6
9.3
16.9
23.0
12.1
23.9
31.7
Slope
1.039
1.093
1.055
0.971
1.075
0.948
0.946
1.010
1.095
0.993
Intercept
yg/m
0.001
-0.402
0.039
0.164
-0.127
0.106
0.163
-0.151
-0.385
0.505
16
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TABLE 4. SUMMARY OF AGENCY PERFORMANCE FOR NO" SURVEYS
Agency
Code
A
B
C
D
E
F
Quarter/
Year
2/77
3/77
4/77
1/78
2/78
4/76
1/77
2/77
3/77
4/77
1/78
2/78
1/78
2/78
4/76
1/77
2/77
3/77
4/77
1/78
2/78
4/76
1/77
2/77
Avg %
Diff.
3j
29.4
0.1
5.9
7.3
-2.1
63.1
-11.3
-18.6
6.7
-0.5
15.5
4.7
2.7
2.7
-0.9
-0.1
** 157.3
4.4
-41.8
-2.5
-6.4
35.7
20.8
5.7
Std.
Dev.
S1
6.3
8.6
8.4
1.3
10.7
88.8
4.5
9.0
11.0
17.5
38.2
84.4
18.1
6.1
5.9
22.2
350.2
12.3
6.2
17.6
20.5
42.0
13.1
17.0
Slope
1.344
0.902
0.923
1.075
1.091
0.941
0.845
0.878
0.997
1.011
0.818
0.963
1.159
1.082
1.055
1.025
0.505
0.958
0.507
1.074
1.126
1.027
1.012
0.883
Intercept
ug/m
-0.060
0.191
0.244
-0.014
-0.260
0.579
0.203
-0.070
0.098
0.084
0.473
0.007
-0.148
-0.191
-0.084
-0.348
2.333
0.143
0.092
-0.135
-0.394
0.310
0.956
0.349
** Laboratory data not used for computing composite results.
(Continued)
17
-------
TABLE 4 (Continued)
Agency
Code
F
(cont'd)
G
H
I
EPA/QAB
Quarter/
Year
3/77
4/77
1/78 .
2/78
4/76
1/77
2/77
3/77
4/77
1/78
2/78
4/76
1/77
2/77
3/77
4/77
1/78
2/78
1/78
2/78
4/76
1/77
2/77
3/77
Avg %
Diff.
^
-16.5
9.5
6.1
9.6
** 5885.2
27.3
** 105.1
22.2
12.8
2.3
-3.6
14.5
-11.2
-8.6
15.7
21.9
14.3
4.2
0.6
-10.1
1.4
9.3
-8.0
1.3
Std.
Dev.
Si
10.2
6.0
5.9
2.4
7835.4
21.3
6.4
7.4
16.2
3.2
12.5
11.6
4.3
10.8
4.6
12.9
4.8
8.6
10.7
14.0
0.7
4.2
2.8
2.3
Slope
0.910
1.016
1.049
1.098
-2.180
1.050
2.085
1.184
1.000
1.035
1.079
1.249
0.878
0.914
1.116
1.051
1.108
1.137
1.061
1.043
1.018
1.050
0.948
1.036
Intercept
yg/m
-0.037
0.111
-0.001
-0.038
44.680
1.034
0.013
0.078
0.181
-0.015
-0.244
-0.203
0.018
-0.005
0.081
0.211
0.035
-0.250
-0.069
-0.343
-0.002
0.167
-0.040
-0.031
** Laboratory data not used for computing composite results.
(continued)
18
-------
TABLE 4 (Continued)
Agency Quarter/ *$,* «J; ' Slope Intercept
d. S.j ug/m
EPA/QAB 1/78 6.4 2.6 1.058 -0.014
(cont'd) 2/78 -9.4 22.9 1.103 -0.391
Composite 4/76 24.6 48.9 1.058 0.120
1/77 4.3 19.5 0.977 0.338
2/77 0.0 19.4 0.993 0.035
3/77 4.8 14.0 1.015 0.075
4/77 1.3 23.5 0.918 0.154
1/78 5.6 14.5 1.048 0.012
2/78 -1.2 28.8 1.080 -0.234
19
-------
function of time. The curves for d. ± S. describe a band of one standard
deviation above and below d.. The band is very roughly ± 20% for both sulfate
J
and nitrate. The significance of the band is that approximately 2/3 of all
the laboratory analyses agree with the "true" values as determined by Rockwell
to within ± 20%.
Ideally, the composite values of d. should oscillate around zero, and
J
the differences from zero are probably related to the population size and to
the accuracy and precision of both Rockwell and the participating laboratories.
Exactly what this relationship is and how much variation around zero might be
expected are not clear at this time.
Although the above statistical treatment is not mathematically rigorous,
it does demonstrate that laboratory performance has remained essentially
constant over the lifetime of the program. The lack of dramatic improvement
is not completely unexpected since most of the laboratories have participated
in similar EPA surveys prior to the beginning of the Western Q.A. Program.
S02 Analysis
S02 samples consist of standard ampules containing freeze-dried solutions
of sodium sulflte and tetrachloromercurate. The "true" value for each sample
is obtained by the Rockwell laboratory by analysis of at least 10 replicate
samples. The usual quality control procedures were used for each analysis.
Table 5, taken from the third quarter 1978 report, summarizes the S02
results since the beginning of the program. Composite results are shown
graphically in Figure 1. Approximately 2/3 of all the analyses agree with
20
-------
TABLE 5. SUMMARY OF AGENCY PERFORMANCE FOR S02 ANALYSIS
Agency
Code
A
B
C
D
Quarter/
Year
4/76
1/77
3/77
4/77
1/78
2/78
3/78
4/76
3/77
4/77
1/78
2/78
3/78
4/76
1/77
3/77
4/77
1/78
2/78
3/78
4/76
1/77
3/77
4/77
1/78
Avg %
Diff.
3i
-24.4
-28.3
-18.7
-14.2
6.1
8.6
3.2
-25.3
1.5
-33.7
9.8
-4.1
-18.7
9.5
-2.6
2.4
10.2
1.6
21.0
0.6
1.7
-2.5
-10.5
-58.9
2.1
Std.
Dev.
sj
19.3
35.9
8.4
50.2
3.7
4.6
3.3
38.5
10.9
46.9
18.5
20.1
31.7
3.9
3.7
7.0
9.3
7.1
2.3
8.7
9.8
2.9
6.3
26.9
3.7
Slope
0.949
1.013
0.910
1.292
1.000
1.030
1.066
1.100
0.862
0.391
0.974
1.142
1.099
1.119
1.005
1.032
1.157
0.969
1.204
1.139
0.963
0.977
0.923
0.776
0.985
Intercept
ug/m
-8.972
-14.095
-5.987
-18.727
3.730
3.216
-2.673
-15.615
10.998
8.718
4.883
-8.911
-13.526
-0.733
-1.408
0.728
-1.859
1.710
0.725
-8.132
1.689
0.287
-0.643
-19.789
1.765
(continued)
21
-------
TABLE 5 (Continued)
Agency
Code
D
(cont'd)
E
F
G
H
Quarter/
Year
2/78
3/78
4/76
1/77
3/77
Mil
1/78
2/78
3/78
4/76
1/77
3/77
4/77
1/78
2/78
3/78
4/76
1/77
3/77
4/77
1/78
2/78
3/78
4/76
1/77
3/77
Avg %
Diff.
*i
3.8
5.8
4.7
-7.6
-5.6
-5.3
-2.8
-2.2
4.9
-11.4
-23.3
-4.5
0.2
1.1
-20.0
9.5
23.9
-7.7
-12.7
-5.2
-0.9
-19.6
7.6
-2.7
0.4
-24.7
Std.
Dev.
5d
2.2
7.2
10.2
5.5
3.3
8.3
11.4
3.2
5.5
6.2
12.2
4.6
13.6
7.1
25.2
10.8
29.6
18.5
11.3
9.4
4.5
18.6
4.2
7.0
11.0
25.6
Slope
1.041
1.074
0.980
1.023
0.937
0.993
0.977
0.999
1.012
0.876
0.668
0.888
0.905
0.950
0.286
0.937
1.348
1.097
1.018
0.764
0.983
0.533
1.053
1.062
0.931
0.995
Intercept
yg/m
0.135
-2.422
2.488
-8.276
1.208
-1.405
1.781
-0.918
1.439
-0.117
7.490
4.731
4.054
3.795
34.284
9.104
-10.974
-8.223
-10.473
12.145
1.471
25.314
0.645
-5.954
3.010
-12.075
(continued)
22
-------
TABLE 5 (Continued)
Agency
Code
H
(cont'd)
I
0
K
EPA/QAB
Composite
Quarter/
Year
4/77
1/78
2/78
3/78
2/78
3/78
4/77
2/78
3/78
4/76
1/77
3/77
4/77
1/78
4/76
1/77
3/77
4/77
3/78
4/76
1/77
3/77
4/77
1/78
2/78
3/78
Avg %
Diff.
*j
2.8
-2.4
-33.3
8.1
-4.8
-5.7
-47.7
1.9
7.8
1.6
-4.0
-11.9
-16.4
-5.5
4.6
1.1
-9.6
-0.6
11.5
-2.0
-7.8
-9.4
-15.4
1.0
-4.6
2.6
Std.
Dev.
si
10.1
30.7
27.1
0.0
15.5
5.7
33.7
3.9
5.4
3.1
3.1
10.2
16.5
12.8
10.3
6.9
9.6
4.1
4.1
21.8
16.0
13.0
31.7
12.9
20.5
13.8
Slope
0.992
1.058
1.019
^^^LfAf
H HW
1.129
0.936
0.407
1.043
1.074
1.011
1.000
0.978
1.033
1.003
0.974
0.945
0.980
0.999
1.092
1.038
0.962
0.952
0.883
0.989
0.943
1.048
Intercept
ug/m3
0.492
-8.848
-20.119
^u^u^
J* V*X
-9.250
-0.524
15.000
-1.910
-0.620
0.597
-2.484
-4.838
-10.078
-1.509
2.855
3.320
-3.378
0.146
0.724
-3.474
-2.264
-1.973
-1.028
0.975
2.256
-1.598
*** Data based on a single sample analysis.
23
-------
60
40
20
n
u
^•20
•
SO' 3j * Sj
/
/
. \ /
\ '
\ /
X-N y
V.^ , N f* .^
^AV /
^V^^V
- / x% /'\ *^j "
t % / \ »
w \ S
60
40
20
NO
20
M 0
^^ w
-20
so2
"*\ 7
\ ^"•*««. ~~** " i
. % ' *
^f ^
, /\/ J
, v
v /
\ /
\t
'I
20
-20
20
« 0
-20
CO
\
Figure 1. Composite quarterly performance evaluation for
all surveys. Graphs show 7. and 3" + S, 1n
.
S,
units of percent difference as a function of time
since the beginning of the program. Each point
1s obtained by averaging all the analysis data
for one given quarterly survey. The CO, SOp, NOl
and SO^ data commence in the fourth quarter of
1976. The NOo evaluation began in the first
quarter of 1977.
24
-------
the Rockwell analyses within the percentage limits defined by d. ± S.. For
_ J j
S02> the d. ± S. band is approximately between + 16% and -23%. Thus the
overall S02 performance is roughly comparable to that of SOT and NOZ. The
composite d. appears to show a small negative bias which might be explained
J
by degradation of samples during the period between the analysis at Rockwell
and the analysis at the other laboratories. In view of this and other un-
certainties, this explanation is highly conjectural. A significant anomaly
appears to exist in the fourth survey as indicated by the large values of
cf. and S. (d. = -15.4%, S. = 31.7%). For this particular survey, a sample
homogeneity problem is suspected since at least three of the eleven labora-
tories reported very large negative differences. In addition, the first
batch of analyses carried out at the Rockwell laboratory had to be discarded
because of unusually high scatter, while a second batch appeared to give more
reasonable results.
NOp Analysis
NOp samples consist of standard ampules containing solutions of sodium
nitrite. The "true" value for each sample is obtained by the Rockwell
laboratory by analysis of at least 10 replicate samples. The usual quality
control procedures were used for each analysis.
Table 6, taken from the 3rd quarter 1978 report, summarizes the N02
results since the beginning of the program. Composite results are shown
graphically in Figure 1. The results for N02 appear to be qualitatively
different from those of SOj, NO^, and S02 in that the band defined by d.
± S. is narrower, and there appears to be a genuine trend towards improved
J
25
-------
TABLE 6. SUMMARY OF AGENCY PERFORMANCE FOR NO ANALYSIS
Agency
Code
A
B
C
D
E
Quarter/
Year
1/77
2/77
3/77
4/77
1/78
2/78
3/78
1/77
2/77
3/77
4/77
1/78
2/78
3/78
1/77
2/77
3/77
4/77
1/78
2/78
3/78
2/78
3/78
1/77
2/77
3/77
Avg %
Diff.
*j
62.6
-9.4
0.2
-4.4
7.0
7.0
-7.2
-8.4
-10.2
-19.1
3.8
6.3
3.7
-6.0
-1.0
-6.1
0.1
1.1
8.1
0.6
-4.4
0.6
-6.0
7.4
-13.5
4.0
Std.
Dev.
sj
54.9
7.4
6.3
13.6
9.7
10.7
5.0
7.3
8.9
27.1
12.4
6.4
5.5
2.1
2.8
4.4
9.5
2.7
4.6
2.1
3.0
3.5
1.9
6.9
11.9
6.1
Slope
1.086
0.996
0.931
0.904
0.992
0.939
1.005
1.028
1.000
1.037
0.958
1.004
0.967
0.984
1.009
0.987
0.820
1.007
1.042
0.990
1.007
0.970
0.915
0.961
0.976
0.964
Intercept
ug/ml
0.136
-0.025
0.017
0.008
0.022
0.031
-0.033
-0.033
-0.028
-0.052
0.018
0.018
0.016
-0.019
-0.004
-0.018
0.048
0.001
0.012
0.003
-0.021
0.009
0.010
0.031
-0.029
0.019
^continued;
26
-------
TABLE 6 (Continued)
Agency
Code
E
(cont'd)
F
G
H
I
Quarter/
Year
4/77
1/78
1/77
2/77
3/77
4/77
1/78
2/78
3/78
1/77
2/77
3/77
4/77
1/78
2/78
3/78
1/77
2/77
3/77
4/77
1/78
2/78
3/78
1/77
2/77
3/77
4/77
Avg %
Diff.
*j
6.7
8.8
19.8
-18.7
-12.4
-8.5
-7.2
10.4
-7.0
5.0
-11.9
-0.5
-2.7
10.3
2.2
-5.6
-5.2
-1.2
5.6
-26.1
2.3
1.1
-7.9
5.8
-0.2
11.7
-0.9
Std.
Dev.
si
8.5
5.6
18.4
3.3
7.4
12.5
2.3
7.5
7.3
10.8
4.4
6.8
2.5
7.5
3.1
2.7
3.1
7.4
21.4
37.3
5.3
5.1
1.0
8.6
40.5
15.8
4.9
Slope
0.973
1.020
1.261
0.879
0.941
1.020
0.926
0.996
0.969
0.946
0.967
0.933
1.003
1.018
0.998
0.998
0.918
0.932
0.841
1.077
0.987
0.962
0.935
0.981
0.763
0.909
0.969
Intercept
ug/ml
0.025
0.022
-0.034
-0.020
-0.021
-0.025
-0.001
0.028
-0.012
0.023
-0.029
0.014
-0.008
0.028
0.005
-0.022
0.007
0.014
0.050
-0.082
0.010
0.011
-0.006
0.018
0.051
0.051
0.009
(continued)
27
-------
TABLE 6 (Continued)
Agency
Code
I
(cont'd)
EPA/QAB
Composite
Quarter/
Year
1/78
2/78
3/78
1/77
2/77
3/77
4/77
1/78
2/78
3/78
1/77
2/77
3/77
4/77
1/78
2/78
3/78
Avg %
Diff.
*i
9.0
4.7
-5.0
-1.6
-9.2
1.3
-2.5
2.6
-1.6
-11.0
9.4
-8.9
-1.0
-3.7
5.3
3.2
-6.8
Std.
Dev.
SJ
7.1
7.1
1.7
6.1
2.1
10.9
3.6
5.4
6.7
3.2
27.6
14.7
15.7
16.3
7.7
6.7
3.8
Slope
1.017
0.962
0.998
0.927
0.919
1.274
0.924
0.982
0.931
0.949
1.013
0.935
0.961
0.982
0.999
0.968
0.973
Intercept
yg/ml
0.023
0.020
-0.034
0.012
-0.003
-0.074
0.015
0.013
0.011
-0.024
0.017
-0.010
0.006
-0.004
0.016
0.015
-0.018
28
-------
data quality. For the first four surveys the standard deviation S. was 15%
•J
or greater, while for the last three surveys S. decreased monotonically down
J
to less than 43.. In the last three surveys in 1978, the level of agreement
between the laboratories and Rockwell has been generally very high.
CO Analysis
3 3
CO samples are contained 1n 0.85 m (30 ft ) aluminum cylinders. Three
different concentrations were submitted for analysis in each survey. Repli-
cate analyses are performed in the Rockwell Quality Assurance Laboratory
using a Bendix nondispersive infrared analyzer, and an NBS SRM cylinder con-
taining 95.0 ppm CO in air is used as the standard. The "true" value is
established by analysis of at least five cylinders of each concentration.
The results of all the CO surveys are for the most part very satis-
factory. Table 7 shows summary data for all laboratories. Composite results
are shown graphically 1n Figure 1. The standard deviation S. has been
generally less than 10% since the beginning of the program. Thus approxi-
mately 2/3 of the laboratories report CO concentration which agree with
those determined by Rockwell to within 10% or better. As indicated in the
first annual report, the good agreement between the various agencies and
Rockwell 1s probably due to the fact that agencies use cylinders for cali-
bration that contain CO at ambient levels and require no dilution. The CO
concentrations supplied by vendors are apparently sufficiently reliable for
this particular analysis.
29
-------
TABLE 7. SUMMARY OF AGENCY PERFORMANCE FOR CO ANALYSIS
Agency
Code
A
B
C
D
E
Quarter/
Year
4/76
1/77
2/77
4/77
1/78
2/78
4/76
4/76
1/77
2/77
4/77
1/78
2/78
4/76
1/77
2/77
4/77
1/78
2/78
4/76
1/77
2/77
4/77
1/78
2/78
Avg %
Diff.
"i
5.1
5.4
4.0
1.3
-3.2
-0.6
5.8
0.8
-5.4
-17.1
-0.7
2.0
-4.2
-3.7
4.3
6.7
-1.4
-5.0
-18.6
-2.3
-1.0
-1.1
-0.7
-2.3
-0.2
Std.
Dev.
V
5.7
2.7
4.2
2.1
3.4
2.6
12.2
6.2
5.7
34.0
10.9
7.7
3.4
5.0
4.7
6.9
1.8
3.0
13.8
7.1
4.7
10.2
13.3
5.6
8.5
Slope
1.073
1.052
1.030
1.009
1.005
1.003
0.956
0.997
0.968
1.076
0.989
1.014
0.993
1.019
1.079
1.126
0.985
0.973
1.043
0.994
0.979
1.022
0.981
0.986
0.999
Intercept
ppm
-0.264
-0.017
0.042
0.049
-0.602
-0.113
0.969
0.108
0.005
-2.213
0.026
0.101
-0.454
-0.621
-0.493
-0.584
0.016
-0.279
-3.532
-0.138
0.146
-0.314
0.182
-0.081
0.016
(continued)
30
-------
TABLE 7 (Continued)
Agency
Code
F
G
EPA/QAB
Composite
Quarter/
Year
1/77
2/77
4/77
1/78
2/78
4/76
1/77
2/77
4/77
1/78
2/78
4/76
1/77
2/77
4/77
1/78
2/78
4/76
1/77
2/77
4/77
1/78
2/78
Avg %
Diff.
*i
-2.9
-0.4
-3.6
-5.6
-0.5
8.2
6.7
6.5
0.5
-7.7
10.7
0.5
-2.0
-2.2
-0.6
-1.4
-1.2
1.4
1.1
1.1
-0.7
-2.8
-2.1
Std.
Dev.
si
5.8
3.8
4.4
3.9
2.8
7.2
2.5
8.1
4.9
3.8
7.8
1.7
3.2
1.5
1.5
0.6
1.2
7.6
5.7
11.0
9.2
5.2
9.0
Slope
0.939
0.985
0.995
0.993
0.972
1.033
1.041
1.032
1.033
0.957
1.005
1.002
1.007
0.991
0.979
0.979
0.977
1.018
1.009
1.033
0.991
0.985
0.999
Intercept
ppm
0.319
0.086
-0.279
-0.529
0.324
0.431
0.295
0.348
-0.197
-0.484
1.510
-0.034
-0.284
-0.127
0.140
0.136
0.146
-0.049
0.029
-0.216
0.052
-0.179
-0.286
31
-------
Weighing Survey
The second weighing survey was begun in November 1977, and was completed
in March 1978. This survey was very similar to the one conducted during the
first year of the Western Q.A. Program. Twelve sets of 3 weights, each
containing a 1, 2, and 5g weight, slightly modified by filing away some of
the mass, were cleaned and weighed several times on two different balances
over a period of several days. Each balance was calibrated just prior to use
with an NBS certified set of Class S weights. One set was sent to each
participating agency, which then weighed the objects and reported results to
Rockwell. The objects were reweighed after return to insure that no signif-
icant change had occurred during transit.
In the second survey, all agencies met the target range (± 1 mg) for all
of their weighings. The sample range (± 0.5 mg) was met by 84% of all
weighings made by all agencies. Thus the gross discrepancies observed in the
weighings of three agencies, reported in the first annual report, have been
eliminated, and there appears to be no weighing problems left. Table 8,
taken from the second weighing survey report, summarizes the results from all
the agencies.
A third weighing survey, which will include all groups in the East and
Uest, is scheduled for early in 1979.
H4gh Volume Flow Rate Measurement
The second high volume flow rate measurement survey was conducted in
the second half of 1977. For this purpose, Rockwell submitted audit devices
32
-------
TABLE 8. SUMMARY OF WEIGHING SURVEY
Agency
Code(a)
A
B
C
0
El
E2
F
G
H
'l
h
J
K
L
M
N
0
Deviations From Rockwel 1
(Nominal Value in mgxlO)
1 gram
-8
3
-1
-5
1
-2
3
-4
-6
-1
-1
-3
-1
-2
-4
1
6
2 gram 5
-1
2
1
-7
9
-2
2
-3
-2
0
0
0
-1
0
-3
1
5
Target Sample
gram Range ^ Range ^
-6 ++4 +
-1 +++ +++
-2 +++ +4-1-
-6 +++ +
-4 -HH- -M-
-4 ++++++
-2 +-H- +-H-
-2 +++ -m-
-4 +++ -H-
2 +++ +++
1 -H-h 4-H-
-2 +++ +-H-
-2 -H-I- -m-
-2 +++ +++
-6 -HH- -H-
-4 +++ -I-H-
1 -m- -H-
(a) Two entries from same agency indicates weighings using two different
balances.
(b) Target range: +1 mg; Sample range: +0.5 mg. A (+) sign means
weighing within designated range.
33
-------
to participating agencies together with a test protocol. Agencies used the
devices and at the same time performed a normal calibration. Agencies reported
their measured flow rates as well as additional pressure and temperature data
from which Rockwell calculated "true" flow rates. The results of the compar-
ison between values measured by each agency and calculated by Rockwell are
summarized in Table 9. This table gives each agency's calibration error,
which is defined as the percent difference between the indicated flow and the
"true" flow, measured at 1.132 m3/min (40 ft3/min).
A comparison between the first and second surveys indicated that
substantial improvements in the calibration results had occurred, although
some of the sites still showed large discrepancies. One problem that has
not been resolved concerns the two agencies which use flow controllers. The
audit device has been found to be inadequate when used in conjunction with
the flow controllers, and no solution has yet been found for this problem.
In the two survey reports, it was suggested that a major problem in
flow calibration was the lack of a definite, uniform set of instructions,
issued by EPA, covering procedures, calculations, and data reporting. This
deficiency has apparently been resolved by the publication of a comprehensive
document entitled, "Investigation of Flow Rate Calibration Procedures
Associated with the High Volume Method for Determination of Suspended
Particulates" (2). This EPA document discusses in great detail the problems
involved in calibrating high volume samplers, and recommends procedures for
correcting and reporting all flow data to the same standard conditions of
temperature and pressure. The document has been distributed to all the
Western Q.A. participants, and hopefully additional improvement in the
34
-------
TABLE 9. SUMMARY OF RESULTS IN THE SECOND HIGH VOLUME SURVEY
Agency
A
B
C
D
E
F
G
H
Site
1
1
1
1
1
1
1
1
Calibration
Win
2.
2.
-0.
3.
-1.
-2.
-4.
. / 1
4
7
8
2
9
5
7
Error, %
.132CMM
12.
4.
-3.
5.
0.
-4.
-7.
3
8
9
5
1
6
3
/ Max.
17.
13.
-7.
10.
+1.
-7.
-10.
5
2
4
2
9
1
4
Remarks
Calibration
Calibration
Calibration
Calibration
Calibration
Calibration
Calibration
poor, scatter
fair
good
fair
good
good
satisfactory
Flow controller employed,
excessive
no mean-
ingful result. See text.
I
J
1
1
6.
3
8.
4
8.
8
Calibration
fair
Flow controller employed,
no mean-
ingful result. See text.
K
L
M
1
2
3
1
2
3
4
5
1
2
3
4
5
6
7
-0.
0.
-1.
-4.
-1.
-2.
-5.
-6.
-7.
-2.
2.
-7.
-7.
-6.
-3.
5
0
4
4
8
7
3
5
3
4
8
1
5
1
1
0.
3.
0.
-5.
-5.
-2.
-8.
7
6
2
7
9
7
1
-8.5
-8.
-5.
-0.
-8.
-9.
-8.
-5.
2
2
9
0
1
6
1
4.
9.
3.
-9.
-8.
18.
-14.
-12.
-9.
-10.
8.
-9.
-13.
-14.
-8.
8
6
9
1
6
1
0
5
8
7
7
4
7
8
9
Calibration
Calibration
bad point
Calibration
Calibration
Calibration
Calibration
ter high
Calibration
Calibration
Calibration
Calibration
bad point
Calibration
high
Calibration
Calibration
Calibration
Calibration
good
good, one relatively
good
satisfactory
satisfactory
poor, slope low, scat-
fair, scatter
fair, scatter
fair
good, except
satisfactory,
fair
satisfactory
satisfactory
good
high
high
for one
scatter
(continued)
35
-------
TABLE 9 (Continued)
Calibration Error, %
Agency Site
N 1
2
3
4
5
6
7
8
9
10
0 1
P 1
2
3
4
Min. /
-0.3
6.7
-6.4
-1.4
1.1
-7.7
3.8
-4.9
4.5
27.0
-3.2
-3.8
-5.6
-1.0
-1.8
1 . 1 32CMM
-1.0
7.6
-7.2
-4.4
-1.5
-9.4
5.5
-8.7
7.4
17.8
-3.8
-5.1
-6.8
-2.6
0.9
/ Max.
-1.8
12.8
-7.6
-5.1
-3.4
-11.7
7.1
-14.8
16.0
47.6
-5.4
-9.6
-12.8
-4.2
6.9
Remarks
Calibration good
Calibration poor,
Calibration fair
Calibration good
Calibration good
Calibration fair
Calibration fair
Calibration poor,
Calibration poor
Calibration poor,
Calibration good
only four points
high scatter
high scatter
Calibration satisfactory
Calibration fair
Calibration good
Calibration good,
scatter
except for high
36
-------
results will show up In the third survey which is scheduled for the beginning
of 1979.
A pertinent observation concerning the new publication may be offered
here. The document appears to be somewhat difficult for the non-expert,
particularly because of the necessarily complex notation. However, H is
understood that the EPA is planning to conduct special workshops to discuss
and review the contents of the document with operators and other individuals
responsible for implementing the recommendations in the book.
Inter!aborator.y Comparison Study of Metal Samples
One of the requirements of the Western Quality Assurance Program 1s to
duplicate approximately 10% of the analyses performed by a designated labor-
atory (denoted here as Laboratory A) for metals collected with particulates
in high-volume samplers. The method of analysis is atomtc absorption, and the
elements that were originally listed Included Be, Ca, B, Zn, Cd, Cr, Co, Cu,
Fe, Pb, Mn, Mo and N1.
During the first year of the program several filter batches analyzed
both by Laboratory A and by Rockwell disclosed very large discrepancies
between the analyses by two laboratories, and no assignable cause could be
determined. In order to investigate the or1g1n(s) of the differences, a
test program was designed and initiated during September 1977. The test
consisted of a sample exchange program in which synthetic metal samples
prepared by Rockwell were analyzed by both Laboratory A and the Rockwell
Chemistry Laboratory. Three types of samples were chosen in order to in-
vestigate three general sources of discrepancies: contamination, extraction,
37
-------
and analytical procedures. The samples included were as follows:
1. Uncut blank filters.
2. Spiked filters containing known concentrations of Cd, Co, Cr, Cu,
Fe, Mn, Mo, Ni, and Pb. The concentrations were chosen to be
significantly above detection limits.
3. Solutions of the above metals dissolved in 10% HNO~.
In addition to the above analyses, all of the liquid extracts analyzed
by Laboratory A were returned to Rockwell for reanalysis.
The results of this joint testing program were reported to EPA in a
long, detailed report dated January 30, 1978. The principal conclusion
resulting from the study was that the discrepancies between the two labora-
tories could be ascribed primarily to differences in extraction procedures.
Laboratory A extracted metal samples by refluxing the filter samples with a
mixture of nitric acid and hydrochloric acid, and then diluting the concen-
trate with 50% HC1. Rockwell, on the other hand, extracted filter samples
with 10% HN03 and diluted the concentrate also with 10% HNOo. For most
metals, the study disclosed that the 10% HN03 procedure gave good accuracy
and precision in the hands of both Rockwell and Laboratory A, and that the
results were definitely superior to those obtained by means of the 50% HC1
procedure. The low percentage recoveries by Laboratory A in past studies
could be reasonably explained by the relatively poor recovery efficiency
obtained from the 50% HC1 extraction procedure.
For the analysis of Mo and Cr, the 10% HNO^ extraction procedure had to
be modified, however, in order to obtain accurate AA analyses. For both of
38
-------
these metals, the addition of 0.5% lanthanum to both the acid extracts and
the standard solutions resulted in improved accuracy.
The high and variable blank values obtained in the earlier comparison
studies did not occur in the joint study, and hence no conclusions could be
drawn.
As a result of the inter!aboratory comparison study, Laboratory A requested
permission from EPA to change the extraction procedures and adopt the Rockwell
procedure. The change was implemented by Laboratory A early in 1978. Since
that time, three different batches comprising a total of approximately 74
filters were analyzed by Laboratory A and by Rockwell. The results of these
comparisons were summarized in two reports dated June 13, 1978 and September
25, 1978, which have been sent to EPA. Comparisons could be made only for
Cu, Fe, Mn, and Pb, since the concentration of other metals were at or below
detection limit. Figures 2-5 are graphs taken from the latter report. The
analyses for Cu, Fe, and Mn showed major improvement over earlier comparisons.
High data scatter remains a problem, however. For Cu and Fe deposition
levels are sufficiently high so that precision of ± 10% could be reasonably
expected. The deposition levels for Mn and Pb are low in relation to the
10% analytical precision level and high data scatter is to be expected.
39
-------
WESTERN Qfl CU(mg/fmer)
Actual least squares f-it
- Unity (perfect agreement)1ine
SLOPE- 1 .)30
Y INT iC. 01 05
C.O.L. =0.90.870
I
.RMC (MG/FILT)
3.750
0.900"
.) Exposure level at and above which Rockwell can analyze with better than
precision.
Figure 2. Split sample analyses for Cu in hi-vol filters - Comparison
between Laboratory A and Rockwell
40
-------
WESTERN Qfl FE (mq/fHter)
Actual least squares fit
- - - Unity (perfect agreement) line
SLOPE =3.94M-9
Y I NT =0.1222
STNDEVs0. 178Q
C,O.L.»0.83620
I
0.730 l.®00
PMC (MG/FILT)
1 .300
Cl) Exposure level at and above which Rockwell can analyze with better than
+10% precision. .
Figure 3. Split sample analysis for Fe in hi-vol filters -
Comparison between Laboratory A and Rockwell
4.1
-------
r,' ^
Q
WESTERN Off MN
Actual least squares fit
- - —Unity (perfect agreement) line
SLOPE =0.8537
Y I NT =-0.0009
C . 0 . L . =0 . S5SS6
"PMC (HG/FTLT;.
i
i
ClJ' Exposure level at and above which Rockwell can analyze with
better than + 10% precision.
Figure 4. Split sample analysis for Mn in hi-vol
filters. Comparison between Laboratory A and Rockwell.
42
-------
CO
CM
WESTERN Qfl PB (mg/fnter)
_Actual least squares fit
Unity (perfect agreement)!ine
C.O.L.sO.1*6311
(3.160
RMC (MG/FILT)
.200
CD Exposure level at and above which Rockwell can analyze
with better than +10% precision.
Figure 5. Split sample analysis for Pb in hi-vol filters. Comparison
between Laboratory A and Rockwell.
43
-------
SECTION 4
CALIBRATION SYSTEM AUDITS
Calibration System Audits of air monitoring stations operated by partici-
pating groups is a major task in the Western and Eastern Q.A. Proorams. Table 10
shows a list of all the sites audited and the dates of the audits during the period
between September 1977 and September 1978. The audit procedures, the audit
devices, operational checks, and the standards used in the field audits were
described in the first annual report, and hence the information will not be
repeated here.
The format for reporting audit results has undergone considerable
change during the course of the program. Prior to June 1978, audit results
were given in terms of linear constants describing the response of each
analyzer to known pollutant concentrations. The relationship was described
by an equation of the form C = A + BX, where C is the concentration in ppm,
X is the analyzer output measured in some convenient form (mv, volts, %
chart, chart divisions, etc.) and A and B are linear constants obtained by
linear regression analysis. In the audit report two pairs of linear
constants were tabulated, namely the pair derived from the latest station
multipoint calibration and the pair derived from the audit measurements.
The comparison between the two sets of data was shown graphically by
drawing the two straight lines (i.e., station and audit lines) on the same
C ys_ X graph. Differences between the station calibration and audit results
were evaluated by calculating the percent difference in C at the nominal
full scale output. (Full scale was defined according to the output parameter
i use at the station; for example, full scale was defined as 1 volt output
44
-------
TABLE 10. SUMMARY OF AUDITS PERFORMED BY ROCKWELL DURING THE PERIOD
SEPTEMBER 1977 TO SEPTEMBER 1978
Agency
C-a
C-b
State of Colorado
Site.
1
023
CARIH
CAMP
Greel ey
Arvada
Date
Nov. 1977; March 1978; June 1978;
Sept. 1978
Nov. 1977; March 1978; June 1978;
Sept. 1978
Oct. 1977; Feb. 1978; May 1978; Aug.
1978
Oct. 1977; Feb. 1978; May 1978; Aug.
1978
Oct. 1977; Feb. 1978; May 1978; Aug.
1978
Oct. 1977; Feb. 1978; May 1978
EPA/Custer, MT
EPA/EMSL-RTP
Colorado Springs Oct.1977; Feb.1978; May 1978; Aug.
1978
Mel by
Grand Junction
Custer
RTP
EPA/EMSL Las Vegas
(Northrop Services Inc.)
EPA/Corvallis
(Pacific Northwest
Laboratory)
III/Imperial Valley
Hae Koolie
B&W
2
3
6
Mobile
Oct.1977; Feb.1978; May 1978; Aug.
1978
Nov.1977; March 1978
May 1978
Nov.1977; March 1978; May 1978;
Aug.1978
Dec.1977; April 1978; July 1978
Jan.1978; April 1978; July 1978
July 1978
Dec,1977
Dec.1977
Dec.1977; April 1978
April 1978
State of Montana
BHHngs Jan.1978; April 1978; Aug.1978
Laurel April 1978
Hwy Junction Jan.1978; April 1978; Aug.1978
(continued)
45
-------
TABLE 10. (Continued)
Agency
Site
Date
State of Montana
(continued)
Mill creek
Broudy
Microwave
Hebgen Park
Lions Park
Alpine West
Lincoln School
Malfunction
Junction
Jan.1978
Jan.1978; April 1978
Jan.1978; April 1978
April 1978; Aug.1978
April 1978; Aug.1978
Jan.1978; April 1978
April 1978; Aug.1978
April 1978
State of New Mexico Reservation
Substation
Water Tank
State Calib.
NOAA Boulder
State of North Dakota Stanton
Bismarck
U /U. A6
a D
State of Utah Price
Huntington
Bountiful
Provo
Magna
Ogden
Cedar City I
Cedar City II
Dec. 1977;
Sept. 1978
Dec. 1977;
Sept. 1978
Dec. 1977;
Sept. 1978
Sept. 1978
May 1978
Jan. 1978;
Jan. 1978;
Dec. 1977;
Sept. 1978
Jan.
Jan.
Jan.
Jan.
Jan.
Jan.
Nov.
1978;
1978;
1978;
1978;
1978;
1978;
1977;
April 1978
March 1978;
March 1978;
March 1978;
April 1978;
April 1978;
March 1978;
April
Apri 1
April
April
April
Apri 1
June
1978;
1978;
1978;
1978;
1978;
1978;
1978
; June 1978
June
June
June
July
July
June
July
July
July
July
July
July
; Sept
1978;
1978;
1978;
1978
1978
1978;
1978
1978
1978
1978
1978
1978
. 1978
(continued)
46
-------
TABLE 10. (Continued)
Agency Site Date
State of Utah Cedar City III Nov.1977; April 1978
(continued) $tate Calib> jan.1978; April 1978; July 1978
Woodward-Clyde Roosevelt June 1978; Sept.1978
Hot Springs
State of Wyoming Patrick Draw Dec.1977; March 1978; June 1978;
Sept.1978
47
-------
or as 100 chart divisions, etc.). Since in this reporting format the
magnitude of B depends on the units of the output parameter, comparison of
calibration constants among different instruments and agencies was difficult.
At the request of EPA a second method was adopted for reporting audit
results, starting with audits performed after June 1978. The second method
compares the concentrations delivered to the analyzer from the audit device
to those predicted from the observed instrumental response and the latest
station multipoint calibration. Mathematically, the results are expressed
in the form C2 = a + BC,, where C2 is the station concentration, C, is the
audit concentration, e is the slope, and a is the intercept. Perfect
agreement between station and audit is represented by the "unity line" 6=1,
c* = 0. Audit reports show graphs of C2 vs Cj, and the values of a and B are
given in tabular form. The advantage of the second method is that B is non-
dimensional, and its value is independent of the analyzer range and the units
used to express analyzer output.
The percent difference between station concentrations are readily
expressed in terms of the magnitude of a and s by means of the equation
c -c r 1
% diff = 100 x p l =100 (6-1) + -£— (2)
cl I Ll J
In order to evaluate the station performance the percent difference is
calculated at the nominal full scale of the analyzer (for example: C, = 0.5
ppm for most NO analyzers). Since normally the magnitude of a/c, is small
compared to e-1, the percent difference is approximately a constant repre-
sented by the quantity 100 (0-1). It is this latter relationship which makes
B a useful comparison parameter.
48
-------
Although the two methods for evaluating performance appear to give
different measures of comparison, it has been shown in previous audit reports
that the two methods are in fact equivalent.
In August 1978, EPA published a set of proposed quality assurance regula-
tions under EPA 40 CFR Part 58, "Air Quality Surveillance and Data Reporting;"
Appendix A - Quality Assurance Requirements for State and Local Air Monitoring
Stations (SLAMS) (1). The proposed regulations describe still a third method
for evaluating calibration performance. The regulation requires calculating
the percent difference d.. for each audit point, and then computing the average
and standard deviation for all the d.'s. The average percent difference d. and
' J
the standard deviation S. are used to estimate the upper and lower probability
limits (measured as a percent) which comprises 95% of all the audit data and can
be used to predict where future measurements are expected to lie. The calculations
outlined in Appendix A have been applied to audits carried out since August 1978.
(it should be noted that Appendix A is expected to be revised in the near future,
and we understand that the use of d. and S. for calibration system audits will be
dropped.) The audit reports since August 1978 include tables of d. and S., but
no attempts have been made to interpret these data.
During the first two years of the program, over 150 Calibration System Audits
have been performed; hence, a very large amount of data has been collected. Seven
quarterly audits have been performed in the EPA/EMSL laboratory at Research Triangle
Park (RTP), N.C. for the purpose of comparing standards and procedures between
Rockwell and EPA. The results of these special audits have been very satisfactory
as the differences between the two laboratories have been generally S% or less.
Table II shows a summary of overall performance for each type of pollutant
being audited. The table shows the total number of audits, the average percent
error (calculated as described earlier in Section 4 buth without regard to
49
-------
TABLE II. SUMMARY OF CALIBRATION SYSTEM AUDIT RESULTS
No. of Avg. Percent Percent of Audits
Pollutant Audits Error With Error of 10% or Less
CO 73 6,0 86
CH4/THC 63 8.5 75
N0x 78 11.4 63
NO 90 12.3 64
N02 69 11.5 67
S02 151 12.0 64
0, 108 12.9 53
50
-------
sign) and the percent of the audits for which the calibration error is 10%
or less. The 10% criterion has been adopted as an arbitrary but reasonable
measure of "satisfactory" performance. The last column in Table 11 gives a
good qualitative indication of the relative calibration accuracy for the
various pollutants and the results clearly reflect the relative complexity
of the calibration methods.
Figure 6 presents some evidence on the impact of the QA program on the
quality of the data generated by the participating groups. Figure 6 shows a
remarkable improvement in the calibration accuracy for NO, HO , and N09.
A fi
For the first two quarters, the observed average errors were in excess of
202. In the last quarter, the average errors decreased to approximately 5%.
For S02 a somewhat different pattern is observed. During the first two
quarters the average error was greater than 20%. Several groups displayed
large calibration differences caused by errors in procedure and/or calcula-
tion. After these large errors were eliminated, the average percent errors
have remained essentially constant at about 10%. This may well be the
ultimate limit that can be expected for the current calibration methods.
The average percent error for CO has been approximately 5% since the
second quarter. This is excellent agreement and it clearly Indicates that
calibration of CO presents no difficulties. This conclusion Is also consistent
with the results of the Interlaboratory CO performance survey described 1n
Section 3.0. It 1s thus evident that CO data generated by the western groups
1s of relatively high quality. The situation for CH^/THC Is comparable although
not quite as good as CO, even though a gradual Improvement in audit results
might appear to have occurred. The maximum observed in the second quarter
51
-------
NO
20
10
(10)
1 2 3 U 5 6 7
(9)
20
io
(19)
(8) (9)
(IT)
o
20
10
0
1 23^567
(20) (27N
(25)
1 2 3
1 2 3
5 6 7
(7)
(12)
(15)
123^567
Horizontal Axis:
Quarterly Audit
Cycle
Vertical Axis:
Average %
Difference
CO
123^567
20
CH, /THC
dp)
123^56 7
Figure 6. Average calibration error vs audit cycle. Numbers
in parentheses indicate total number of audits per quarter.
The seven quarters above extend from the first quarter of 1977
through the third quarter in 1978.
52
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is attributed to a single audit result in which a very large calibration
error (subsequently found to have been caused by improper calibration
procedure) unduly affected the average. If this non-typical station were
removed from the average, the observed pattern would be as shown by the
dotted line. The relatively high error in the third quarter has to be viewed
with caution since the average is made up of only three audits.
The most significant calibration problem encountered in the program is
that of ozone. A small downward trend in the calibration error may have
occurred, but compared to the other pollutants the improvement is small and
the average percent error has remained at or above 10%. Of course, the major
problem in the calibration of ozone is that there is no stable, reliable
standard readily adaptable for field use. EPA has recognized this problem
and has recently issued a number of documents in draft form (3,4) to help
monitoring groups in improving the ozone calibration procedures. In addition,
a recent proposed EPA change (5) designates UV photometry as the new reference
method for ozone calibration. We expect the ozone data to begin showing
improved accuracy as more groups adopt this simpler calibration procedure.
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SECTION 5
TECHNICAL ASSISTANCE
In accordance with the provisions of the contract, Rockwell has
provided technical assistance to the various participating agencies as
requested by the Project Officer. Some of the assistance has been relatively
minor, and consisted of telephone discussion of various agency problems,
citing of literature references or help with procedural difficulties.
Much technical assistance is given informally during site evaluations
and particularly during field audit visits where the exchange of ideas and
information between Rockwell and Agency personnel is oftentimes extensive
and intensive.
The following is a list of interactions with agencies during which
Rockwell provided technical assistance.
Agency A - Traceability and certification were established for three CO
cylinders sent to Rockwell by this agency. Notes and advice on the vapor
pressure correction used with a Hastings Bubblemeter Kit with flows over 1
liter/min were also supplied. The correction factor given is the one used
by Rockwell during field service (November 1977).
Agency B - Several meetings and discussions were conducted with this agency
in an effort to resolve problems encountered during an inter!aboratory sample
survey for SO^. No resolution to the problem was readily apparent although
the fact that the agency used the BaClp method for SOT as opposed to the
more accurate MTB (methylthymol blue) method may be involved. A full
xplanation of the interlaboratory comparison methods at each of the sample
54
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concentrations levels was also presented to this agency at a meeting held
at the agency's headquarters (December 1977).
Agency C - This agency requested certification of the SCL permeation rate
and the ppm concentration for an NO cylinder. Traceability was to be
established to NBS materials but the agency standards have yet to arrive
(January 1978).
Agency D - This agency sought specific assistance with an SOT-NOr problem.
While the agency had no problem analyzing liquid samples, there was some
question as to the effectiveness of the ultrasonic extraction procedure
currently in use. It was suggested that filters spiked with known amounts of
material be extracted as per normal to resolve this problem (February 1978).
Agency E - Rockwell personnel visited this agency in April 1978 subsequent
to a request for technical assistance with the NOI, SO? and As analyses.
The instrumentation used for this analysis was functioning correctly. Sample
preparation was cited as a possible cause for the earlier problem seen with
the NOZ analysis.
In April 1978, three cylinder standards (CO, NO and CH.) were certified
by Rockwell and traceability to NBS supplied.
An extensive split-sample program was conducted with this agency for
the analysis of heavy metals on high volume filters. Approximately 74 agency
filters were analyzed by Rockwell between December 1977 and June 1978 for
Al, As, Cd, Cu, Fe, Pb, and Zn. In the earlier analyses the indicated
agreement between the two laboratories was good for Cd, Cu, and Pb, fair for
As, and poor for Al, Fe and Zn. The comparisons completed in June 1978
55
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showed remarkable improvement in the analyses of Fe and Zn. The As com-
parison also showed improvement, possibly as a result of the implementation
by the agency of the more precise automated-nameless technique used by
Rockwell. Some differences in the Al analysis still remain.
Agency F - An extensive split-sample program was conducted with this agency
for the analysis of heavy metals on hi-volume filters. Presumably identical
hi-vol filter strips were analyzed for SB, As, Be, Cd, Cu, Pb, Hg, Se, and
Zn by the Rockwell Chemistry group and by the agency laboratory. Problems
were seen with the Cd, Hg, and Zn results while those for Pb and Cu were
relatively good (November 1977 - May 1978). Later in the year (May 1978)
this agency had difficulties during an inter!aboratory survey and requested
replicate samples. The problems experienced with SOT were traced to a
defective absorption solution.
Agency G - Two cylinders of NO and CO were shipped to Rockwell to establish
NBS traceability and absolute concentration values. The purpose of this
task was to resolve a problem concerning the accuracy of the vendor's analysis
Results were sent to the agency personnel as well as to the Project Officer
(September 1978).
Agency H - Eight cylinders were sent to Rockwell for certification and to
establish NBS traceability. All were methane cylinders containing approx-
imately 9-16 ppm CH^. The results of the analyses were sent to the agency
(September 1978).
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SECTION 6
PLANS FOR NEXT YEAR
The general plans for next year are to continue the current program of
Quality Control Reference Sample Audits, Calibration System Audits and technical
assistance. A major addition, of course, is the implementation of the Eastern
Q.A. Program. During the next year the five or six groups which have not yet
been evaluated will have to be visited, and the evaluation reports for all the
Eastern Q.A. groups will be completed. Quality Control Reference Sample Audits
and Calibration System Audits will be expanded to include the participation of
the eastern groups. While the need for technical assistance in the west may be
expected to decline, the requirements 1n the east are difficult to estimate.
With the implementation of the Appendix A guidelines, some additional
effort may be required towards modification of existing audit procedures,
particularly with respect to ozone. The calculation procedures in Appendix A
are likely to be changed by EPA during the next year, and therefore the
reporting format may have to be modified once more. Improved methods for
evaluating Individual and overall performance as a function of time should be
developed, and some additional statistical analysis may be desirable. The
use of the computer for storing and analyzing Calibration System Audit data
should be made a high priority task.
As Indicated In the first annual report, since the ultimate purpose of
the program 1s to help the participating groups 1n Improving the quality of
their data base, some modifications 1n the program may become desirable as
the collective experience of all groups increases. Thus constant reevalua-
tion of the program is in order, and changes will be made whenever they
57
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seem appropriate, given the consent and cooperation of the Project Officer
and all interested parties.
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REFERENCES
1. Environmental Protection Agency; Proposed Regulatory Revision to 40 CRF,
Part 58 (Appendix A), "Air Quality Surveillance and Data Reporting,"
Federal Register, Vol. 43, August 7, 1978, p 34906.
2. Environmental Protection Agency; "Investigation of Flow Rate Calibration
Procedures Associated with the High Volume Method for Determination of
Suspended Parti oil ates," EPA-600/4-78-047, August 1978.
3. Environmental Protection Agency; "Technical Assistance Document for the
Calibration of Ambient Ozone Monitors," available from EPA, Department E
(MD-76), Research Triangle Park, N.C. 27711.
4. Environmental Protection Agency; "Transfer Standards for Calibration of
Ambient Air Monitoring Analyzers for Ozone," EPA Publication available
in draft form from EPA, Department E (MD-76), Research Triangle Park,
N.C. 27711.
5. Environmental Protection Agency; Proposed Amendments to 40 CRF Part 50
(Appendix D), "Measurement of Ozone in the Atmosphere," Federal Register,
Vol. 43, June 22, 1978, p 26971.
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TECHNICAL REPORT DATA
(Please read Inunictions on the reverse before completing/
1. REPORT NO.
EPA 600/7-79-136
3. RECIPIENT'S ACCESSION NO.
4. TITLE ANDSUBTITLE
QUALITY ASSURANCE IN SUPPORT OF ENERGY RELATED
MONITORING ACTIVITIES. Annual Report No. 2
5 REPORT DATE
June 1979
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Mark Cher
8. PERFORMING ORGANIZATION REPORT NO
AMC8303.135AR
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Rockwell International
Environmental and Energy Systems Division
Environmental Monitoring & Services Center
Newbury Park, CA 91320
10. PROGRAM ELEMENT NO.
1NE883
11. CONTRACT/GRANT NO.
Contract No. 68-02-2412
12. SPONSORING AGENCY NAME AND ADDRESS •
U.S. Environmental Protection Agency
Quality Assurance Branch
Environmental Monitoring and Support Laboratory
Research Triangle Park, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
EPA 600/08
15. SUPPLEMENTARY NOTES
16. ABSTRACT
This report describes and summarizes the activities during the second year of
the program named above. The activities described are part of a continuing 5-year
program.
The purpose of the program is to establish a quality assurance data base for
ambient air monitoring in specified geographical areas around oresent and proposed
energy development projects, and to provide technical assistance to enable existing
monitoring networks to achieve a high level of data quality. An initial on-site
review of 18 laboratories and associated field sites was completed during the first
year. Additional laboratories and field sites were evaluated during the second
year. Regularly scheduled laboratury performance surveys are being carried out for
the analysis of sulfate, nitrate, S02, N02, and CO and for weight measurements and
high volume flow rate. Approximately 10% of the analysis performed by a
specified laboratory for metals collected in high volume filters are being repeated
in the Rockwell laboratory. Quarterly field audits are being conducted at specified
monitoring sites. Technical assistance has been provided to participating
monitoring groups, as requested by the Project Officer.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS
t. COSATi Field/Group
Quality Assurance
Ambient Air Monitoring
Site Evaluations
Laboratory Audits
Field Audits
Technical Assistance
Sulfate
Nitrate
S09
NO-
CO
43F
68A
3. ClSTRIbUTION STATEMENT
RELEASE TO PUBLIC
19. SECURITY CLASS (ThisReport/
UNCLASSIFIED
21. NO. OF PAGES
60
2O. SECURITY CLASS /This page/
UNCLASSIFIED
22. PRICE
EPA Form 2220-1 (9-73)
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