United States
Environmental Protection
Agency
Environmental Monitoring
Systems Laboratory
P.O. Box 93478
Las Vegas NV 89193-3478
EPA/60Q/R-92/235
December 1992
Research and Development
Strontium in Water
Intercomparison Study

A Statistical Evaluation of the
September 11,1992 Data
                                6614OHSeNRD.COV-4

-------
            Strontium in Water
          Intercomparison Study
           September 11, 1992
      Environmental Protection Agency
Environmental Monitoring Systems Laboratory
            Las Vegas, Nevada

-------
            UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
                        OFFICE OF RESEARCH AND DEVELOPMENT
               ENVIRONMENTAL MONITORING SYSTEMS LABORATORY-LAS VEGAS
                                  P.O. BOX 93478
                            LAS VEGAS, NEVADA 89193-3478
                                   (702/798-2100)
Dear Participant,
   Enclosed are the results of the Nuclear.Radiation Assessment Division (EMSL-LV)
Intercomparison Study for Strontium in Water; September 11, 1992.

   Please take a few minutes to review this report and the analytical data your
laboratory submitted to us.  If there are any apparent discrepancies, please notify
us immediately.
   We encourage you to make use of the computer-automated data-entry system that
has been in place for some  time now.  As the number of participants increases, and
it becomes unrealistic for us to receive results by mail or FAX, the computer system
will be our only avenue for accepting data.

   If you have any questions or comments,  please send a message via the data-entry
system or contact Frank Novielli at 702/798-2159 or Patricia Honsa at 702/798-2141.
                                          Sincerely,
                                           •rank Novielli
                                          Senior Chemist
                                          Radioanalysis Branch
Enclosure

-------
                 NOTICE

This material has been funded wholly by
the U.S. Environmental Protection Agency.
It has been subject to the Agency's review,
and it has been approved for publication
as an EPA document.

-------
          EMSL-LVIntel-comparison Study: Strontium in Water,  ll-8ep-1992        1/9

   The following pages consist of separate sections for each of the nuclides in this study with four
parts per section. After the first, each part is separated from the next by a new page or a thick
horizontal bar.  The first page of each section is a statistical summary for the nuclide and starts
with a statement of the known value, the control limits, and the warning limits.
   The warning limits are placed at two normalized standard deviations above and below the
known value and the control limits are three normalized standard deviations above and below
the known value. If you keep control charts, these values will be useful for anticipating problems
with the accuracy of your analytical  methods.

   The coin shaped pie chart at the top of the summary page shows the fate of all the samples
sent out in number and percentage terms. The pie chart starts at the top and rotates clockwise.
The first sector represents those participants who submitted analytical results within both the
warning and control limits. The next sector represents those who are in  the warning region but
not out of control. The third sector represents those who are out of control, but have passed
the outlier test.  The fourth sector represents those who have failed the outlier test. The last
sector represents those participants  who have failed to respond properly.  This is the case if no
analytical results were returned, or less than three determinations were reported, or if the results
were received too late. The reeding on the edge of the coin is spaced at one percent intervals, and
the sector shading becomes darker as the  data reliability decreases. Sectors with zero width are
not shown.

   The table in the center shows a number of statistical quantities calculated from the submitted
data based on the mean and median values in relation to the known value, both before and after
outlier removal. The lower pie chart uses the same construction as the upper chart and shows
the distribution of properly submitted data in terms of deviation from the known value divided
into sectors representing one, two, three, and greater than three normalized standard deviations.

   The second part is an alphabetical listing, in lab-code order, of submitted data and several
calculated quantities. An entry that is shaded has been rejected because of one of the reasons
listed above or failure of the outlier test. The fifth and sixth columns are a measure of laboratory
precision.  The Range analysis is a normalized value that you may use to keep precision control
charts. If this value is between 2.0 and 3.0, your analytical process precision is in the warning
zone; if it exceeds 3.0 it is out of control. The eighth and ninth columns are the differences from
the mean of all non-outliers and from the  known value, respectively. A tag symbol may appear in
the last column. Each page with tags has a symbol definition summary at the bottom. If there is
no tag symbol, the data is within the control limits, but it may be in the warning zone.

   The third part is a three-column  listing of result average, tag symbol, and lab-code in average
order excluding those labs not responding properly. In this order, all outliers and out-of-control
results appear at the top or bottom of the  list.
   The last part is two bar chart displays showing frequency distributions of responding
participants. The first chart places the known value at the center and a bar at each 0.2 unit of
expected precision. The second chart places the mean of the reported measurements at the center
and a bar at each 0.2 unit of standard deviation. In both cases,.a bar includes those results within
0.1 unit up to the maximum of six. Any results more than six units from the center value are
shown cumulatively by a shaded bar one past the sixth unit. If the central tendency of the known
value distribution folia away from the center,  an error in accuracy is indicated. If the distribution
is broad, poor precision is indicated. The  mean value distribution is similar but uses the average
and standard deviation of reported results as its basis.

-------
            EMSL-LV Intel-comparison Study: Strontium in Water,  ll-Sep-1992
                                    2/9
Strontium-89                        Statistical Summary                       86 Participants
The known value of this nuclide is 20.0 pCi/1 with an expected precision of 5.0; the control limits
are 11.3 to 28.7; the warning regions are 11.3 to 14.2 and 25.8 to 28.7
20(23.5 %) Failed to respond \
3(3.5 %) Outliers '
5(5.9 %) Out of control
     but not an outlier


         Statistic
                • 51 (60.0 %) Within all limits
Respondents
6(7.1 %) In warning zone
       but within control


          Non-outliers
Mean
Std. Dev.
Variance
%Coef. ofVar.
% deviation of mean from known value
Norm. dev. of mean from known value
Median
% deviation of median from known value
Norm. dev. of median from known value
     23.68
     30.13
    907.79
    127.23
     18.41
      0.12
     19.00
     -5.00
     -0.03
Grand Avg 20.04
             4.84
            23.41
            24.15
             0.19
             0.01
            19.00
            -5.00
            -0.21
8(12.3 %) Mora than 3 norm. S.D. »
6(9.2 %) Between 2 and 3 norm. S.D.'
            ,37(56.9 %) Within 1 norm. S.D.
                           of known value
     14(21.5 %) Between 1 and 2 norm. S.D.

-------
3/9 EM8L-LV Intercomparison Study:
Strontium in Water,
ll-Sep-1992

Strontium-89

Lab

AE
AF
AK
AL
AU
AW
A*
BA
BO
C
CA
OE-
CJ
CK
CQ
CS
C3t
D
DE
DG
DO
DT
DZ
E
EB
EH
EL
FE
HK
HU
1C
J
JE
JS
JY
K
KX
L
LM
LT
M
ME
MQ
MS
• =
0 =

Res. 1
0*0
24.0
20.0
19.0
13.0

15.0

14.0
21.0
22.0
16.0

16.0
19.0
18.0
16.0
238.0
19.0
18.0
21.0
19.0
18.0
31.0
19.0
18.0
16.0
15.0
18.0
19.0
11.0
20.0
20.0
38.0
23.0
24.0
17.0
22.0
21.0

34.0
23.0
30.0
18.0
23.0

Res. 2
0.0
21.0
22.0
21.0
21.0

14.0
- '."'
15.0
24.0
21.0
18.0
-
15.0
19.0
17.0
12.0
22810
18.0
18.0
23.0
20.0
16.0
33.0
21.0
23.0
15.0
18.0
17.0
18.0
12.0
22.0
20.0
27.0
19.0
16.0
15.0
19.0
22.0

34.0
23.0
20.0
19.0
22.0

Res. 3
0,£
23.0
20.0
20.0
14.0
' f ',.
15.0
% ' -'. " '
13.0
21.0
23.0
14.0
f f j f s
17.0
19.0
20.0
14.0
mo
19.0
19.0
18.0
18.0
20.0
33.0
17.0
23.0
16.0
15.0
17.0
18.0
12.0
21.0
22.0
38.0
21.0
22.0
17.0
21.0
21.0

34.0
22.0
26.0
20.0
23.0
No data submitted
Insufficient
data
X S
Exper.
Sigma
0.00
1.53
1.15
1.00
4.36
'
0.58
, •. •.
1.00
1.73
1.00
2.00

1.00
0.00
1.53
2.00
80,61
0.58
0.58
2.52
1.00
2.00
1.15
2.00
2.89
0.58
1.73
0.58
0.58
0.58
1.00
1.15
6.35
2.00
4.16
1.15
1.53
0.58

0.00
0.58
5.03
1.00
0.58
Rng anal
(R + SR)
0,000
0.354
0.236
0.236
0.945
'
0.118
-
0.236
0.354
0.236
0.473

0.236
0.000
0.354
0.473
12.696
0.118
0.118
0.591
0.236
0.473
0.236
0.473
0.591
0.118
0.354
0.118
0.118
0.118
0.236
0.236
1.570
0.473
0.945
0.236
0.354
0.118

0.000
0.118
1.345
0.236
0.118
Normalized deviation
Average
0,00
22.67
20.67
20.00
16.00
; «'
14.67
'> ,
14.00
22.00
22.00
16.00

16.00
19.00
18.33
14.00
258.33
18.67
18.33
20.67
19.00
18.00
32.33
19.00
21.33
15.67
16.00
17.33
18.33
11.67
21.00
20.67
34.33
21.00
20.67
16.33
20.67
21.33

34.00
22.67
25.33
19.00
22.67
TAG SYMBOLS
Determined
to be an outlier
(grand-avg) (known) Tag
*0J4
0.91
0.22
-0.01
-1.40

-1.86

-2.09
0.68
0.68
-1.40

-1.40
-0.36
-0.59
-2.09
82.55
-0.47
-0.59
0.22
-0.36
-0.71
4.26
-0.36
0.45
-1.51
-1.40
-0.94
-0.59
-2.90
0.33
0.22
4.95
0.33
0.22
-1.28
0.22
0.45

4.84
0.91
1.83
-0.36
0.91
IT s Above
U 3 Below
-6J3 x
0.92
0.23
0.00
-1.39
*
-1.85
*
-2.08
0.69
0.69
-1.39
*
-1.39
-0.35
-0.58
-2.08
82.56 x
-0.46
-0.58
0.23
-0.35
-0.69
4.27 It
-0.35
0.46
-1.50
-1.39
-0.92
-0.58
-2.89
0.35
0.23
4.97 IT
0.35
0.23
-1.27
0.23
0.46
*
4.85 It
0.92
1.85
-0.35
0.92
control limit
control limit

-------
EMSL-LV Intel-comparison Study: Strontium in Water, ll-8ep-1992 4/9
Strontium-89

Lab Res. 1 Res. 2
N - '>*'-': i " '--:•• t ,f
NB 31.0 31.0
NJ 18.0 19.0
NT 23.0 22.0
OA 27.0 24.0
OL-" ' ''
PB 20.0 20.0
^^ f f f ff S ffff
,l?p'~ ' '/,''',,'
I*!St ' 7'/' ' ' ' '"" ' /- '"'
' * .. ' .-.-/... ' .-...' ' ,
W&' , ' ' ,„* '
W ', - *•,*'„,-;
PV 19.0 17.0
QU 30.0 29.0
QW 27.0 26.0
QZ 22.0 21.0
R 13.0 15.0
nd ', ' "" ' '
RK 18.0 17.0
RM 22.0 19.0
RN 14.0 16.0
•fctifeii' ''^3'^Vi;
S 17.0 18.0
SC 18.0 18.0
SD 16.0 17.0
SI 16.0 11.0
SS 19.0 20.0
ST 25.0 26.0

i'ttf'' , '- '" t',\ '"'• , ' "jtj&%":;
8Z 17.0 17.0
^ML** ***»'* / *"'" *''**'£' y /f-J$?*
§ ^ ^s^ ^ ^>
"•m^^
TO ,, .^l^t?
TI 16.0 13.0
TL 24.0 17.0
TM
TJP 38*0 40.0
U 17.0 16.0

Average Tag
0.00 x
11.67
• s No data submitted
0 s Insufficient data

Exper. Rng anal
Res. 3 Sigma (R + SR)
' '; ,'" ' ', : ' '' '
30.0 0.58 0.118
19.0 0.58 0.118
22.0 0.58 0.118
26.0 1.53 0.354
,/•-'' - ,, '- -, . '"' ' '
20.0 0.00 0.000
f ' '/ " * / ' f f * ' if/*, *
/' y''' ' /" ' '''','
" '^ -'.A '"'''', > ,' .' ' ''
.,, fc ,;,/, ,// , ,,,/, , .,<- , ,,,

', f ' S s ' s s
20.0 1.53 0.354
30.0 0.58 0.118
28.0 1.00 0.236
20.0 1.00 0.236
15.0 1.15 0.236
, '
18.0 6.58 0.118
26.0 3.51 0.827
13.0 1.53 0.354
&&- tfi-sL'*. "- ' < - '-.
19.0 1.00 0.236
21.0 1.73 0.354
18.0 1.00 0.236
13.0 2.52 0.591
21.0 1.00 0.236
25.0 0.58 0.118

'SJ&'/<"?^/ ;- '' , '-, '
17.0 0.00 0.000
s, $fy "f f/fyf'? <• f'*f "*,
* fstft£ &%f/f'v' * •* * ff f' ff ^ f •' f
^^'U?3;5' //''/;-»'' -'-
%'/*,'};,,',''
13.0 1.73 0.354
12.0 6.03 1.795

38.0 115 0.236
19.0 1.53 0.354
Data sorted by Laboratory
Lab Average Tag
13.33
B^J 14.00
TAG SYMBOLS

Normalized deviation
Average (grand-avg) (known) Tag
'- " '" ', ' ''''*„'' ••
30.67 3.68 3.70 ft
18.67 -0.47 -0.46
22.33 0.80 0.81
25.67 1.95 1.96
'" - •*
20.00 -0.01 0.00
f f f _, / •>
', * * ' *
/ ' f * ^
f f
9
*
18.67 -0.47 -0.46
29.67 3.34 3.35 ft
27.00 2.41 2.42
21.00 0.33 0.35
14.33 -1.98 -1.96
*
17.67 -0.82 -0.81
22.33 0.80 0.81
14.33 -1.98 -1.96
*
18.00 -0.71 -0.69
19.00 -0.36 -0.35
17.00 -1.05 -1.04
13.33 -2.32 -2.31
20.00 -0.01 0.00
25.33 1.83 1.85

, , , •
17.00 -1.05 -1.04
' , ' ' ' *
f f ' f
,*'"''' , *
*
14.00 -2.09 -2.08
17.67 -0.82 -0.81
•
38.67 0.45 6.47 x
9
17.33 -0.94 -0.92
Average
Lab Average Tag Lab
SI 14.00 CS
TI 14.00 BA
ft s Above control limit
x = Determined to be an outlier U = Below control limit

-------
5/9
EMSL-LV Intel-comparison Study: Strontium in Water, ll-Sep-1992

Strontium-89
Data sorted by Laboratory Average
Average
14.33
14.33
14.67
15.67
16.00
16.00
16.00
16.00
16.33
17.00
17.00
17.33
17.33
17.67
17.67
18.00
18.00
18.33
18.33

Tag Lab
RN
R
AW
EH
EL
CJ
CA
AL
K
SZ
SD
U
FE
TL
RK
S
DT
HK
DE

Average Tag
18.33
18.67
18.67
18.67
19.00
19.00
19.00
19.00
19.00
20.00
20.00
20.00
20.67
20.67
20.67
20.67
20.67
21.00
21.00
21.00
Lab
CQ
PV
NJ
D
SC
MQ
E
DO
CK
ss
PB
AK
KX
JY
J
DG
AF
QZ
JS
1C
Average Tag
21.33
21.33
22.00
22.00
22.33
22.33
22.67
22.67
22.67
25.33
25.33
25.67
27.00
29.67 ft
30.67 ft
32.33 ft
34.00 ft
34.33 ft
38.67 x
258.33 x
Lab
L
EB
C
BO
RM
NT
MS
M
AE
ST
ME
OA
QW
QU
NB
DZ
LT
JE
TP
CX
% Frequency distribution of responding labs( expected prec. vs known value)


n S8 .
-6
_
. •• ••
. . f..l.f •II llllll
-'4 exp.prec. * ' }aj^m
value


1 IT - .. . -T
+2 exp. prec. +4


i
+«
% Frequency distribution of responding labs(std. dev. vs mean value)

IU" '-----

-6

• s No data

	
tn
nliii
•4 std. dev. -2 mean
value
submitted TAG SYMBOLS
0 = Insufficient data x s Determined to be an


1 •- . .....
+2 std. dev. +4

ft = Above control
outlier Jl s Below control


i
+6

limit
limit

-------
            EMSL-LV Intel-comparison Study: Strontium in Water,  ll-Sep-1992
                                    6/9
Strontium-90                        Statistical Summary                      85 Participants
The known value of this nuclide is 15.0 pCi/1 with an expected precision of 5.0; the control limits
are 6.3 to 23.7; the warning regions are 6.3 to 9.2 and 20.8 to 23.7
18(21.2 %) Failed to respond -..
4(4.7 %) Outliers •
         Statistic
                ; 61 (71.8 %) Within all limits
Respondents
2(2.4 %) In warning zone
       but within control


          Non-outliers
Mean
Std. Dev.
Variance
% Coef. of Var.
% deviation of mean from known value
Norm. dev. of mean from known value
Median
% deviation of median from known value
Norm. dev. of median from known value
     16.92
     18.88
    356.48
    111.59
     12.80
      0.10
     14.33
     -4.44
     -0.04
Grand Avg 14.50
             2.37
             5.61
            16.34
            -3.32
            -0.21
            14.33
            -4.44
            -0.28
4(6.0 %) More than 3 norm. S.D. .,
2(3.0 %) Between 2 and 3 norm. S.D.
            . 5O(74.6 %) Within 1 norm. S.D.
                           of known value

     11 (16.4 %) Between 1 and 2 norm. S.D.

-------
7/9 EMSL-LV Intel-comparison Study:
Strontium
in Water,
ll-Sep-1992

8trontium-90

Lab

AE
AF
AK
AL
AU
AW
AY
BA
BO
C
CA
CE
CJ
CK
CQ
CS
ox
D
DE
DG
DO
DT
DZ
E
EB
EH
EL
FE
HK
HU
1C
J
JE
JS
JY
K
KX
L
LM
LT
M
ME
MQ
MS
• =
0 m

Res. 1
0#
14.0
15.0
18.0
19.0

18.0
13.0
22.0
14.0
14.0
14.0
14.0
14.0
15.0
12.0
24.0
142.0
14.0
15.0
17.0
14.0
12.0
20.0
15.0
13.0
17.0
15.0
14.0
14.0
10.0
15.0
14.0
10.0
15.0
12.0
15.0
13.0
15.0

18.0
30.0
13.0
14.0
15.0

Res. 2
0.0
15.0
15.0
16.0
15.0

18.0
12.0
20.0
12.0
14.0
13.0
14.0
13.0
14.0
13.0
24.0
SW#
14.0
15.0
14.0
12.0
14.0
20.0
15.0
14.0
16.0
15.0
13.0
14.0
9.0
15.0
16.0
13.0
16.0
12.D
15.0
15.0
14.0

18.0
2&0
15.0
16.0
15.0

Res. 3
0,S
16.0
16.0
16.0
20.0

16.0
13.0
21.0
13.0
14.0
16.0
14.0
12.0
16.0
12.0
21.0
m#
14.0
15.0
16.0
13.0
10.0
20.0
16.0
13.0
16.0
17.0
13.0
14.0
10.0
14.0
15.0
8.0
13.0
13.0
15.0
14.0
14.0

18.0
27*0
14.0
16.0
15.0
No data submitted
Insufficient
data
X s
Exper.
Sigma
0.00
1.00
0.58
1.15
2.65
'
1.15
0.58
1.00
1.00
0.00
1.53
0.00
1.00
1.00
0.58
1.73
mai
0.00
0.00
1.53
1.00
2.00
0.00
0.58
0.58
0.58
1.15
0.58
0.00
0.58
0.58
1.00
2.52
1.53
0.58
0.00
1.00
0.58

0.00
1.63
1.00
1.15
0.00
Rnganal
(R + SR)
o.ooo
0.236
0.118
0.236
0.591
_,
0.236
0.118
0.236
0.236
0.000
0.354
0.000
0.236
0.236
0.118
0.354
11440
0.000
0.000
0.354
0.236
0.473
0.000
0.118
0.118
0.118
0.236
0.118
0.000
0.118
0.118
0.236
0.591 ,
0.354
0.118
0.000
0.236
0.118

0.000
0.364
0.236
0.236
0.000
Normalized deviation
Average
0,00
15.00
15.33
16.67
18.00

17.33
12.67
21.00
13.00
14.00
14.33
14.00
13.00
15.00
12.33
23.00
166.33
14.00
15.00
15.67
13.00
12.00
20.00
15.33
13.33
16.33
15.67
13.33
14.00
9.67
14.67
15.00
10.33
14.67
12.33
15.00
14.00
14.33

18.00
20.33
14.00
15.33
15.00
TAG SYMBOLS
Determined
to be an outlier
(grand- avg) (known) Tag
-5.02
0.17
0.29
0.75
1.21

0.98
-0.64
2.25
-0.52
-0.17
-0.06
-0.17
-0.52
0.17
-0.75
2.94
52.60
-0.17
0.17
0.40
-0.52
-0.87
1.90
0.29
-0.41
0.63
0.40
-0.41
-0.17
-1.68
0.06
0.17
-1.44
0.06
-0.75
0.17
-0.17
-0.06

1.21
4Jfr
-0.17
0.29
0.17
IT = Above
JJ s Below
-6.20 x
0.00
0.12
0.58
1.04
«
0.81
-0.81
2.08
-0.69
-0.35
-0.23
-0.35
-0.69
0.00
-0.92
2.77
52.42 x
-0.35
0.00
0.23
-0.69
-1.04
1.73
0.12
-0.58
0.46
0.23
-0.58
-0.35
-1.85
-0.12
0.00
-1.62
-0.12
-0.92
0.00
-0.35
-0.23
•
1.04
4.62 x
-0.35
0.12
0.00
control limit
control limit

-------
EM8L-LV Intercomparison Study:
Strontium
in Water, 11.8ep-1992
8/9
8trontium-90

Lab
NB
NJ
NT
OA
OL
PB
P0
fE
'P2P
pgr
PV
QU
QW
QZ
R
JRC-
RK
RM
RN
RE
S
sc
SD
SI
88
ST
sir
sz
• ijfiA,
TB
j
s.
TI
TL
TM
TP
TW
U

Res. 1
13.0
19.0
14.0
15.0
'
14.0
' - '

t

19.0
13.0
14.0
13.0
10.0
.,
15.0
11.0
15.0
f ' f
14.0
13.0
12.0
14.0
14.0
9.0
', ' s fff
16.0
''"',, ' '
,'-'' ''i&V,?
'z / " ' •*"*' '',
, ' ''",-•;
14.0
12.0

25*0

15.0

Res. 2
13.0
18.0
14.0
14.0
ff
15.0
,
, •• "r - -
,
•" f f f
21.0
14.0
15.0
12.0
11.0
•"
14.0
14.0
14.0
' /
14.0
14.0
12.0
15.0
15.0
10.0
;! f * / "f v f'f
16.6
', , ' '/••'•? !ft
', , „'„ < ' if*
$ Af" f f j ?' ' '
'$$,'. $,'/,' ' "'„
''f''^'' "
12.0
13.0

25.0

14.0


Res. 3
13.0
17.0
14.0
16.0
- ''„'",

14.0
''' ''' '
'. •;?-;
f f
*' ' s '
, "
^

,
12.0
14.0
13.0
12.0
11.0

'
15.0
13.0
13.0

-
15.0
12.0
12.0
16.0
14.0
11.0
's£,«$;t
'{-?'-'
16.0
''' /?/,*$
&%? '
Exper.
Sigma
0.00
1.00
0.00
1.00
-
0.58
"• '-
.. -• ',
,

4.73
0.58
1.00
0.58
0.58
' ,,
0.58
1.53
1.00
-
0.58
1.00
0.00
1.00
0.58
1.00
f f
0.00
', ''•:'/''*' ' ',' + ,
Rng anal
(R + SR)
0.000
0.236
0.000
0.236

0.118
- - y
*

'
1.120
0.118
0.236
0.118
0.118
*
0.118
0.354
0.236

0.118
0.236
0.000
0.236
0.118
0.236

0.000
f f
Normalized deviation
Average
13.00
18.00
14.00
15.00

14.33


.• '
-
17.33
13.67
14.00
12.33
10.67
-
14.67
12.67
14.00

14.33
13.00
12.00
15.00
14.33
10.00

16.00
•"
(grand-avg) (known) Tag
-0.52
1.21
-0.17
0.17

-0.06




0.98
-0.29
-0.17
-0.75
-1.33

0.06
-0.64
-0.17

-0.06
-0.52
-0.87
0.17
-0.06
-1.56

0.52
'
'^jjijji^Ti,^', \ I-*' - „ '
'/^s|/'-
-;/^y^
v>, '&„
''/"'<
15.0
11.0




S'C

16.0
Data
Average


0.00
9.67
Tag
x

Lab

B^J
' ''£,?, ''*'' '
,;/
1.53
1.00

0.53

1.00
f f f f
f
0.354
0.236

0,lt«

0.236
'
'
13.67
12.00

25,33

15.00


-0.29
-0.87

3,75

0.17
-0.69
1.04
-0.35
0.00
*
-0.23
*
*
*
*
0.81
-0.46
-0.35
-0.92
-1.50
*
-0.12
-0.81
-0.35
•
-0.23
-0.69
-1.04
0.00
-0.23
-1.73
•
0.35
*
*


-0.46
-1.04
•
3.58 x
•
0.00
I^^^HMBMB
sorted by Laboratory Average
Average


• s No data submitted
0 =
Insufficient data
x
10.00
10.33
Tag


Lab Average Tag Lab
ST
JE
TAG SYMBOLS
= Determined to be an outlier
10.67
12.00
ft s Above
U = Below
R
TL
control limit
control limit

-------
9/9
Strontium
EMSL-LV Intel-comparison Study: Strontium in Water, ll-Sep-1992
-90



Data sorted by Laboratory Average
Average
12.00
12.00
12.33
12.33
12.33
12.67
12.67
13.00
13.00
13.00
13.00
13.00
13.33
13.33
13.67
13.67
14.00
14.00
14.00
14.00

Tag Lab
SD
DT
QZ
JY
CQ
RM
AY
SC
NB
DO
CJ
BO
FE
EB
TI
QU
RN
QW
NT
ME

Average Tag
14.00
14.00
14.00
14.00
14.00
14.33
14.33
14.33
14.33
14.33
14.67
14.67
14.67
15.00
15.00
15.00
15.00
15.00
15.00
15.00

Lab
KX
HK
D
CE
C
88
8
PB
L
CA
RK
JS
1C
U
SI
OA
MS
K
J
DE

Average Tag
15.00
15.00
15.33
15.33
15.33
15.67
15.67
16.00
16.33
16.67
17.33
17.33
18.00
18.00
18.00
20.00
21.00
23.00
25.33 x
28.33 x
166.33 x
Lab
CK
AE
MQ
E
AF
EL
DG
SZ
EH
AK
PV
AW
NJ
LT
AL
DZ
BA
CS
TP
M
CX
% Frequency distribution of responding labs( expected prec. vs known value)


10- - - - -

-6

%


10- - - - -

0 -'*



nil v
ittii.if
~4 exp. prec. "2 , *
Joiown
value



+2 exp. prec. **



-M
+6

Frequency distribution of responding labsCstd. dev. vs mean value)
•
•••
MJU -
•lllll.fl
-4 std.'dev. ;2 ' 6
mean
value




+2 std.'dev. *'4


• s No data submitted TAG SYMBOLS ft = Above control
0 s Insufficient data x s Determined to be an outlier ^ = Below control



.;.;.:.
+6


limit
limit

-------