Tritium in Water Intercomparison Study: a Statistical Evaluation of the February 21, 1992 Data


EPA
           United States
           Environmental Protection
           Agency
             Environmental Monitoring
             Systems Laboratory
             P.O. Box 93478
             Las Vegas NV 89193-3478
EPA 600/R-92/062
April 1992
           Research and Development
Tritium in Water
Intercomparison Study

A Statistical Evaluation of the
February 21,1992 Data
                                           5168GR92NRD.COV-4

-------
             Tritium in Water
          Intercomparison Study
            February 21, 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 - FTS 545-2100)
Dear Participant,
   Enclosed are the results of the Nuclear Radiation Assessment Division (EMSL-
LV) Intercomparison Study for Tritium in Water; February 21, 1992.

   This report introduces a new format that we hope is easier to read and interpret.
Although we have tested the software that produces this report carefully, and
compared the results with the previous format, there is a possibility of error. We
encourage you to examine the data and inform us of any apparent discrepancies.

   We especially 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, it becomes unrealistic for us to receive results by mail or FAX.
   If you have any questions or comments, please send a message via the data-entry
system or contact Frank Novielli at 702/798-2159 (FTS 545-2159) or Patricia Honsa
at 702/798-2141 (FTS 545-2141).

                                          Sincerely,
                                          Frank 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-LV Intel-comparison Study: Tritium in Water, 21-Feb-1992 1/8

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
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 falls 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:  Tritium in Water, 21-Feb-1992
                                     2/8
Tritium                             Statistical Summary                      163 Participants
The known value of this nuclide is 7904.0 pCi/I with an expected precision of 790.0; the control limits
are 6633.4 to 9274.6, and the warning levels are 6989.5 to 8818.5
19(11.7 %) Failed to respond «..^
7(4.3 %) Outliers •
9(5.5 %) Out of control '
     but not an outlier


         Statistic
               ; 118(72.4 %) Within all limits
 Respondents
*• 1O(6.1 %) 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
   7697.72
   1576.54
2485475.03
     20.48
      -2.61
      -0.13
   7952.67
       0.62
       0.03
 Grand Avg 7942.78
               702.00
           492803.57
                 8.84
                 0.49
                 0.06
             7975.33
                 0.90
                 0.10
16(11.1 %) More than 3 norm. S.D.
11 (7.6 %) Between 2 and 3 norm. S.D. •
               6(52.8 %) Within 1 norm. S.D.
                            of known value
      41(28.5 %) Between 1 and 2 norm. S.D.

-------
3/8
EMSL-LV Intel-comparison Study: Tritium
in Water, 21-Feb-1992

Tritium
Exper. Rng anal
Lab
A
AB
AE
AF
AH
AI
AJ
AK
AP
AU
AW
AY
AZ
BA
BB
BC
BG
BI
BL
BM
BO
BW
C
CA
O1" ^f
CE
CJ
CK
CM
CN
CO
CP
CQ
CS
, f
Ou '
ex
D
DD
DE
DG
DH
DI
DJ
DL
DM
• 3
0 =
Res. 1
8946.0
9700.0
8460.0
8015.0
7945.0
7820.0
6909.0
8690.0
8083.0
7400.0
7841.0
7785.0
8973.0
7736.0
7803.0
7040.0
8700.0
7040.0
7971.0
8610.0
7500.0
8900.0
7784.0
7695.0
\:$j3$$!te£
8200.0
7900.0
7639.0
-'(•-',,' C;<.>™i~;fi
7041.0
8180.0
7923.0
8600.0
8700.0
\ , f ',"*%', <;• 'i£\*'-. •?
v£ At''ff -." ' f /""•*?
6632.0
8470.0
7962.0
8700.0
8500.0
%&$&''%!''''* '•'i?™''^y^
pf^Pft '<4'^:',
8239.0
7767.0
7570.0
7542.0
8230.0
8200.0
7447.0
9866.0
8318.0
8320.0
No data submitted
Insufficient
data
x =
Sigma ^R
43.51
208.17
83.27
88.62
35.27
155.66
54.95
73.10
72.04
152.75
24.22
72.74
394.62
52.29
102.64
290.01
115.47
60.31
5.60
88.90
5.60
400.00
42.99
59.82
IS&M&ftl - -
151.00
100.00
80.07
j ^ _ j ' f ! :
225.97
255.80
38.52
219.39
152.75
7<> -syr, -'- ,- - . '
$'*, ^-^ ;„,;-, "?,.
524.88
176.55
75.52
8.12
266.53
83.27
644.57
315.91
209.59
20.00
+ SR)
0.065
0.299
0.120
0.132
0.046
0.232
0.079
0.107
0.107
0.224
0.031
0.100
0.588
0.078
0.152
0.434
0.150
0.090
0.008
0.127
0.007
0.598
0.064
0.086
0,636
0.224
0.150
0.120

0.306
0.381
0.058
0.314
0.224


0.686
0.253
0.112
0.012
0.374
0.120
0.895
0.470
0.289
0.030
Average
8989.33
9533.33
8433.33
8009.33
7985.67
7656.67
6892.33
8672.33
8149.33
7566.67
7827.00
7835.67
8596.67
7785.00
7895.67
7040.00
8633.33
7033.33
7975.33
8680.00
7496.67
8500.00
7784.00
7714.00
i'414&67;.>
8340.00
7800.00
7643.00

6892.00
8203.33
7961.67
8773.33
8666.67
,-"• •--. -^ /','•.••"

7633.00
7965.00
7560.00
7534.00
8033.33
8133.33
7723.33
9826.00
8225.00
8340.00
TAG SYMBOLS
Determined to
be an outlier
Normalized deviation
(grand-avg) (known) Tag
2.29
3.49
1.08
0.15
0.09
-0.63
-2.30
1.60
0.45
-0.82
-0.25
-0.23
1.43
-0.35
-0.10
-1.98
1.51
-1.99
0.07
1.62
-0.98
1.22
-0.35
-0.50
,* ,:\sBJ38k'"- '< -.
0.87
-0.31
-0.66
- . ,"' - ''.„' " ,! '-
-2.30
0.57
0.04
1.82
1.59
"' *• '\, ','-.j ft. "'j ' *' ' ' T
^ '*"'.+ * '"
-0.68
0.05
-0.84
-0.90
0.20
0.42
-0.48
4.13
0.62
0.87
ft s Above
Jl = Below
2.38
3.57 ft
1.16
0.23
0.18
-0.54
-2.22
1.68
0.54
-0.74
-0.17
-0.15
1.52
-0.26
-0.02
-1.89
1.60
-191
0.16
1.70
-0.89
1.31
-0.26
-0.42
*8JW^',V*x/
0.96
-0.23
-0.57
•>, ', '}' ;-"+'.'.?.
-2.22
0.66
0.13
1.91
1.67
*, " •• -",',,
> ; -^,- *. '
-0.59
0.13
-0.75
-0.81
0.28
0.50
-0.40
4.21 ft
0.70
0.96
control limit
control limit

-------

EMSL-LV Intel-comparison Study
: Tritium
in Water, 21-Feb-1992
4/8
Tritium

Lab
DR
DT
E
EA
EB
EH
EL
EN
EW
EX
*ffft *V gffttf
>^l

FE
FJ

Res. 1
8090.0
8000.0
7333.0
7920.0
7707.0
7150.0
8588.0
7643.0
5180.0
6929.0
ffttf%fftl
7900.0
7780.0

Res. 3
8280.0
8000.0
7324.0
8030.0
7891.0
7510.0
8994.0
7482.0
7038.0
6829.0
vzxp' ' " f* '{" yv>f''y''?'"'
%$$$•'&$$%%*'•,
**'^>£'^fe'
"7800.0
8100.0
Exper.
Sigma
96.08
0.00
4.90
66.57
93.50
180.10
226.76
193.36
1249.39
54.85
* "^ ^ '"//!,'"'" " ''
'^'^f^^f,,'. ''•',; •'{,
''"-,, %?~ ''f,4. '".^\,
100.00
300.22
Rng anal
(R + SR)
0.142
0.000
0.007
0.090
0.138
0.269
0.304
0.288
2.479
0.075
'" '/••" r,', f" ' "
'• //,':''j'^""/,t''<-,:l
'"- t ?M'*l'f
0.150
0.449
?F]Ki,^i6Mo^^3^4lpE"IM7^^ 7W;4#?~>'0.07<^
FL
'iivi y
•W\Jjfc
FZ
GE
HI
HJ
HK
^ " < ;".
7682.0
"•/.x ""^f/-'fi'i/f,", '"";"•"
fy'l**/"?- '^-P^'.^CV
8470.0
8318.0
7247.0
8270.0
8278.0
'^<7^&^£fj&j>f2?'tfc> ,
7764.0
~~"jl?;-",;S~^*f
"^$"^^?*i^J
7910.0
7985.0
7209.0
8260.0
8544.0
""'/'^ STitii'^T
8385.0
' '"",?, ' "'/t'"""' ' ' '"
'•%'*'£' *%$' '"%"".''',:!'
8270.0
8372.0
7130.0
8220.0
8544.0
?"?'>fC*— 4»'**.Vrfk*^'''"
384.40
tf^.* ffff^ f ,„ ,-,, ,,„ ,
/"' /" '/''I, /,, '
283.79
209.59
59.66
26.42
153.57
f/2tf f'Ll i' " "
0.526
' '»'' "/' v ' /
v '-''}'£ ''*',+ ''A
0.419
0.289
0.087
0.037
0.199


Average
8176.67
8000.00
7328.00
7996.67
7789.33
7333.33
8849.33
7461.00
5626.67
6892.00
', ' '? y"" ,'"'?;'*'",',;"
^/4fvv%x" i'$&&
>,'Jf'r 2, &%^,
"7960.00""
7793.33
"v-'aMe^ai^
7943.67
"••" ; '•'/' ^'/"*"
Y; ''-;-" ~*L, '*;"'." '*
8216.67
8225.00
7195.33
8250.00
8455.33
' M j£ ^'A*^"^»*NTf' '
Normalized
(grand-avg)
0.51
0.13
-1.35
0.12
-0.34
-1.34
1.99
-1.06
-5.08
-2.30
''"', ", '?%?'< '"?, ;";"'",/
'!$,• l/^;i^|,,|:s.'
^ij''&]3§^
-0.09 "
-0.33
^''l&Sljip
0.00
, ,,„,„ HHtfyf.tfftttf^ 	 v tty'f
''' '<'% *^'f ' ?'f?A
0.60
0.62
-1.64
0.67
1.12
s,,fv, -.«, •*,,„. s,,*^,,?*
deviation
(known) Tag
0.60
0.21
-1.26
0.20
-0.25
-1.25
2.07
-0.97
-4.99 U
-2.22
', " '"' ^ '"? S" "' '//, ?' ' '?" *Z
?%$$$&,,"/*•#?£ ',*•' % ''
H:i'^^{{-?!» :/
-o"oi
-0.24
Ip^jTpT^
0.09
ff~t,,f >^ />,„,,„*,,,, ,^,#y ^ ^
f^,\< '',',s%$rh,v','f \*/&
0.69
0.70
-1.55
0.76
1.21
' "", ' ' '"> ,"/""'," '"' •"
''''HQRj;'\^IKiYiU?g^vlJt'f ^t^yu*^v J^M^bHS-ti '",^ffi*$^,f,,, ' , '"'
— ' ^ " ' ,
120.60
184.73
433.96
76.75
307.51
81.02
100.67
152.75
126.64
; ;-^; ;,-;
490.72
64.29
109.97
120.01
135.02
208.17
^'"V /
214.00
;: '''' 4- * '"
'/ f j '" ''
-0.30
0.52
-1.44
-0.01
3.15 ft
1.15
-1.93
-3.44 U
-0.34
^'r'"^' VV"
1.04
0.49
-0.12
1.68
-0.59
0.58
.- yi '•""'.-',• •• :''• ',''
0.99
r;-i7ll3/v.- --x\'.
-0.81
ft s Above control limit
$ s Below control limit

-------
5/8
EMSL-LV Intel-comparison Study: Tritium in Water,
21-Feb-1992

Tritium

Lab
MA
ME
ML
MN
MQ
MS
MT
MV
N
NH
NI
NJ

l*sli! -
NP
OA
ij^ ''
OL
OM
OTi
PB
PC
PD
PJ-~5
PM-

Tcwp ^
*
PQ
PV
Q
QC
QD
QI
:4d?
QK
QL
QM
QP
jflT
QtT
QW
QX
QZ
R
RM
RN
RO
RQ

Res. 1
7313.0
8690.0
10216.0
,V "V-.^ -r
8340.0
8180.0
7580.0
" ' "" -Af- / *
7699.0
7740.0
7864.0
6600.0

'X , ~\ >• • '#?, "•'-*! '
8133.0
7400.0
" 4 ' ' ' 't N ''*' 'V '
' " '-'V •'& 'V'
6622.0
-^T^Sv)^
7154.0
6203.0
8300.0
-/€l,:^">-V%^fc:J
?;?: :1 jlSlOS''
^a;" ,;7 S^sS-V^
; ""-^'-v^ '*'•>,*';•< \, ^^"

8930.0
7823.0
7717.0
8059.0
8300.0
_4Z17JL,
Jipl^^;
8145.0
7640.0
6965.0
8196.0
^tl^tpf
;";?l?'BfcV:<:i
7201.0
8773.0
8498.0
7910.0
7162.0
8500.0
8272.0
6940.0

Res. 2
7508.0
8410.0
10044.0
>*TV?&
8510.0
8030.0
7595.0
• ' '*'
7669.0
7535.0
7526.0
6500.0

iff ' ,-X^-$"^'-
9074.0
7750.0
Xvi. ' > ; — /A/
\i""'}--\/ *'*Y-'?
6847.0
•*^'";?Tv£???S
^j,^'.!^' ;
7121.0
6256.0
8660.0
§<.,^,-~>?^
Q\'
{,?•
•• §•• " s •• ' •* ***<
. '^"^ ••
9080.0
7905.0
8479.0
8024.0
8600.0
8138.0
jfp^yKS
8180^0
7716.0
6988.0
8361.0


6900.0
8819.0
8306.0
8040.0
7113.0
8500.0
8376.0
7060.0

Res. 3
7475.0
8360.0
10058.0
'>, J* ~.';,'? '&- ••
8290.0
8090.0
7650.0
V"v"'^l?^^
7634.0
7801.0
7333.0
6700.0

''£'•>/'*?>• &'• "'-'y^.
8022.0
7880.0
'' v,' •• r '* *' ' *
-,---''"•• ' '•,*>"^'"'^;
7072.0
;?2f,^ifW-
7226.0
6078.0
^^;72po.p_
^S^MM^
''^£' . ,* ,
8360.0
8012.0
8915.0
8007.0
8750.0
8563.0
^Srl^ISi
8189.0
7592.0
6900.0
8436.0
Exper.
Sigma
104.38
177.87
95.55
;vV;? - -'"
115.34
75.52
36.88
^i;l- -I','-; ¥
32.49
139.34
268.78
100.00
'<.' < ' * •* . s'.f
'\ ^s A 'v' ,
578.00
248.26
'••-* vv'^ - '
" • •""? • f " -
224.99
,;<;' ;> %; , ^ '-", ^^
53.73
91.40
760.61
^f^il^^''''-^'//
;i"-''"ll-'0i68: /'-
'"••„_ ;fv/^J. 4 ,-. i'«fs y
\ / > ' ' , % ' 'I
" •• ,* ..
379.87
94.77
606.35
26.57
229.12
299.88
^^|^ :r- £»-,"'""
'.^V^-WjW'-'"
23.31
62.52
45.68
121.69
J-SSS^.J'^'V 'VJA &£'!&'' '•' 'Af""}}"*? '"*•'' "f '.' "•^•ti t_-.' 'C.
^^l^^4
69o6r6
8630.0
8326.0
8180.0
7193.0
8600.0
8127.0
6940.0
• = No data submitted
0 3
Insufficient
data
x =
C^lpX/' '
"" 173.78
98.55
105.56
135.02
40.30
57.74
125.06
69.28
Rnganal
(R + SR)
0.146
0.247
0.129
' -\- •
0.164
0.112
0.052
"'--, -* '
0.049
0.199
0.397
0.150


0.787
0.359


0.336
-.;."" '—. ',(
0.079
0.133
1.175
•*.-*., ': ' "
f 0.60i:, ,i

V. ^ ^

0.538
0.141
0.896
0.039
0.336
0.433
0.601 ;
0.033
0.093
0.066
0.179
0.042 :

0.225
0.141
0.144
0.202
0.060
0.075
0.186
0.090
Normalized deviation
Average
7432.00
8486.67
10106.00
':' ' '",-' '•'
8380.00
8100.00
7608.33

7667.33
7692.00
7574.33
6600.00

- - -'
8409.67
7676.67


6847.00
-' ~*'('.
7167.00
6179.00
8053.33
- -'' ""-i-f^<;
83.67
"'


8790.00
7913.33
8370.33
8030.00
8550.00
8472.67
, 7,33,
8171.33
7649.33
6951.00
8327.67
233,33
" , - V " '
7000.33
8740.67
8376.67
8043.33
7156.00
8533.33
8258.33
6980.00
TAG SYMBOLS
Determined to be an outlier
(grand-avg) (known) Tag
-1.12
1.19
4.74
"v- '-; V' ' r',: ••' ;
0.96
0.34
-0.73
"- -,; "s-~?~~%%.
-0.60
-0.55
-0.81
-2.94

- -, -, „ ,, , ,.,
1.02
-0.58

'' * '' v - " J ' ; '
-2.40
11 ~- / v
-1.70
-3.87
0.24
";-^' r;^-V;-f;.
--;/ - -17.J23V , v;
' ",- ' " ' ' •" • 'v " * \
'.
' ,. ,
1.86
-0.06
0.94
0.19
1.33
1.16
;,[,-. -WM :. ,,r
0.50
-0.64
-2.17
0.84
-16.90.
, - -v' '""" •"" -- !'!:
-2.07
1.75
0.95
0.22
-1.72
1.29
0.69
-2.11
ft = Above
U 3 Below
-1.03
1.28
4.83 ft
- ;'; -'.A.^ V ;
1.04
0.43
-0.65
'-'!" °'%Z. •-?& '
-0.52
-0.46
-0.72
-2.86

- ' • - •" 'v\r
1.11
-0.50
'* * ^ * \ •• ^ '
/ '' *• ^',^ ' ' t^'W ,
-2.32
;"^/>;J> ^'~
-1.62
-3.78 ^
0.33
-' ,.v-!K;r,sv*^-
"1^»18 -.*--- Xx''"
• » '-~ *"*. '
, ','- ' .• « ,--•-

1.94
0.02
1.02
0.28
1.42
_l-25__
fitSiT-.rx-p
0.59
-0.56
-2.09
0.93
-16.82 X
;-; !J-,'' ^ '; ' * >'• ,
-1.98
1.83
1.04
0.31
-1.64
1.38
0.78
-2.03
control limit
control limit

-------
EMSL-LV Intercomparison Study: Tritium
Tritium
Lab Res. 1 Res. 2
RR 8049.0 8150.0
RS 5936.0 6000.0
RX 8808.0 8410.0
RY 7944.0 8337.0
S 7500.0 7640.0
SA 10900.0 9680.0
SC 7510.0 7630.0

SF 7287.0 7446X)
SI 7350.0 7500.0
SK 7330.0 7330.0
SM 7730.0 7790.0
SN 7939.0 8093.0
r ^^ ^W ' /' , i ' ? i ' ' ' i V
SS 7393.0 7481.0
ST 8848.0 8244.0
SU 7214.0 7194.0
SW 8390.0 8220.0
SY 8559.0 8371.0
SZ 7887.0 7798.0
T 8210.0 8140.0
TA 7650.0 7520.0
U 8880.0 8940.0
W 8760.0 8740.0
X 9087.0 8370.0
Y 8447.0 8169.0
Z 7903.0 7779.0

Exper. Rng anal
Res. 3 Sigma (R + SR)
7997.0 77.80 0.114
5978.0 32.55 0.048
8336.0 253.85 0.353
7919.0 234.45 0.313
7590.0 70.93 0.105
9340.0 820.33 1.317
^^7760;,9 ~^JL2~5,:°~5 	 fi-M^L..
:f&^>:^Miy''^.'''''- , A:-> 
-------
7/8
Tritium

Average
7608.33
7633.00
7633.33
7636.67
7643.00
7649.33
7656.67
7667.33
7676.67
7692.00
7714.00
7723.33
7746.67
7768.67
7784.00
7785.00
7789.33
7793.33
7799.33
7800.00
7827.00
7835.67
7850.67
7859.67
7863.33
7895.67
7900.00
7901.00
7913.33
7943.67
7961.67
7965.00
7975.33
7985.67
EMSL-LV Intel-comparison

Data sorted
Tag Lab
MT
CX
SC
LE
CK
QL
AI
N
OA
NH
CA
DI
JY
I
C
BA
EB
FJ
Z
CJ
AW
AY
L
SZ
SM
BB
FE
J
PV
FL
CP
D
BL
AH
Average
7996.67
8000.00
8009.33
8010.67
8030.00
8033.33
8043.33
8053.33
8065.33
8066.67
8100.00
8126.67
8133.33
8142.67
8149.33
8166.67
8171.33
8176.67
8187.67
8190.00
8203.33
8216.67
8223.33
8225.00
8225.00
8250.00
8258.33
8259.00
8327.67
8340.00
8340.00
8344.33
8355.67
8370.33
Study: Tritium in Water, 21-Feb-1992

by Laboratory Average
Tag Lab
EA
DT
AF
SN
QC
DG
R
PD
RR
RY
MS
KX
DH
1C
AP
LF
QK
DR
HR
T
CO
FZ
SW
GE
DL
HJ
RO
Y
QP
DM
CE
SY
LR
Q
Average Tag
8376.67
8379.00
8380.00
8409.67
8430.33
8433.33
8455.33
8472.67
8486.67
8500.00
8518.00
8533.33
8540.33
8550.00
8596.67
8633.33
8666.67
8670.00
8672.33
8680.00
8740.67
8753.33
8773.33
8790.00
8816.67
8849.33
8989.33
9057.33
9341.00 ft
9533.33 ft
9826.00 ft
9973.33 ft
10106.00 ft
12163.67 x



Lab
QZ
KM
MQ
NP
JP
AE
HK
QI
ME
BW
RX
RN
ST
QD
AZ
BG
CS
LA
AK
BM
QX
W
CQ
PQ
U
EL
A
X
JM
AB
DJ
SA
ML
HP
% Frequency distribution of responding labs( expected prec. vs known value)

I
° -6


T "f ""
'4 exp. prec. "2

•••••••
.llihlililiii.. __ _ _ _ __
i 0 +2 exp. prec. +4
Known
value
• 3 No data submitted TAG SYMBOLS ft s Above control
0 s Insufficient data x == Determined to be an outlier -11 = Below control


+6

limit
limit
-------
             EMSL-LV Intel-comparison Study: Tritium in Water, 21-Feb-1992         8/8



Tritium


 %             Frequency distribution of responding labs(std. dev. vs mean value)
 lo-p^

   m  —

    I
  0-
     -6            -4   std. dev.   -2             o             +2  std. dev.   +4            +6
                                             mean

                                             value
-------