&EPA
           United States
           Environmental Protection
           Agency
          Office of Research and
          Development
          Washington, DC 20460
EPA/600/R-97/021
February 1997
Uranium-Radium in
Water Performance
Evaluation Study

A Statistical Evaluation of the
December 6,  1996 Data
                                       002RSL9T.COV

-------
      Uranium-Radium in Water
    Performance Evaluation Study
         December 6, 1996
   Environmental Protection Agency
National Exposure Research Laboratory
  Characterization Research Division
         Las Vegas, Nevada

-------
            UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
                        OFFICE OF RESEARCH AND DEVELOPMENT
                      NATIONAL EXPOSURE RESEARCH LABORATORY
                    CHARACTERIZATION RESEARCH DIVISION-LAS VEGAS
                                  P.O. BOX 93478
                            LAS VEGAS, NEVADA 89193-3478
                                   (702/798-2100)
Dear Participant,

   Enclosed are the results of the Analytical Sciences Branch (CRD-LV)
Performance Evaluation Study for Uranium-Radium in Water; December 6, 1996.

   The known value for each analysis was determined by gravimetric methods,
checked by chemical analyses performed by CRD-LV's  Radiochemistry Laboratory,
and compared to the participating laboratories' grand average.

   The expected precision, determined by the known value, was taken from
Table 3. Laboratory Precision:  One Standard Deviation Values and Control Limits
for Various Analyses", which is based on data accumulated over the years by the
Performance Evaluation Program, and can be found in the Environmental Radioactivity
Performance Evaluation Studies Program and Radioactive Standards Distribution
Program information brochure.

   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 Stephen Pia at 702/798-2102 or Patricia Honsa at 702/798-2141.

                                          Sincerely,  /I
                                          Stephen Pia
                                          Team Leader
                                          RADQA Program
Enclosure

-------
              NOTICE

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

-------
      CRD-LV Performance Evaluation: Uranium-Radium in Water,  6-Dec-1996    1 / 20


   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 hy 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.  The eighth and ninth columns are the differences from the mean of all non-outliers and
from the known value, respectively. 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. 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.

-------
2/20   CRD-LV Performance Evaluation: Uranium-Radium in Water,  6-Dec-1996


     The Range Analysis(R + SR) is calculated from the range, mean range and standard error of
  the range values.  The range is the difference between the maximum and minimum remilts for the
  laboratory. The mean range is calculated by multiplying the expected precision by 1.693(for three
  results).  The standard error of the range is calculated by multiplying the mean range by 2.575(for
  three results), subtracting the mean range from this product, and dividing the result by 3.  If the
  range is greater than the mean range, then the range analysis is calculated by subtracting the
  mean range from the range, dividing the result by the standard error of the range and adding 1.
  If the mean range is greater than or equal to the range, then the  range analysis is calculated by
  dividing the range by the mean range.
     The normalized deviation of the mean from the grand average is calculated from the deviation
  of the mean from the grand average and the standard error of the mean values. The deviation of
  the mean from the grand average is calculated by subtracting the grand average from the
  average of the laboratory's three results. The standard error of the mean is calculated by
  dividing the expected precision by the square root of 3(the number of results). The normalized
  deviation of the mean from the grand average is calculated by dividing the deviation of the mean
  from the grand average by the standard error of the mean.
      The normalized deviation of the mean from the known value is calculated from the deviation of
  the mean from the known value and the standard error of the mean values.  The deviation of the
  mean from the known value is calculated by subtracting the known value from the average of the
  laboratory's three results. The standard error of the mean is calculated by dividing the expected
  precision by the square root of 3(the number of results). The normalized deviation of the mean
  from the known value is calculated by dividing the deviation of the mean from the known value by
  the standard error of the mean.
      A complete explanation of the statistical calculations involved in the report may be found in
  the Environmental Radioactivity Performance Evaluation Studies Program information brochure
  [Draft Revision of EPA-600/4-81-004], available from Patricia Honsa, CRD-LV, 702/798-2141.

-------
         CRD-LV Performance Evaluation:  Uranium-Radium in Water,  6-Dec-1996    3/20
Uranium (Natural)                  Statistical Summary                      153 Participants
The known value of this nuclide is 5.0 pCi/l with an expected precision of 3.0; the control limit*
are 0.0 to 10.2; the warning regions are 0.0 to 1.5 and 8.5 to 10.2
38(24.8 %) Failed to respond «.
5(3.3 %) Outliers
         Statistic
              . 1O9(71.2 %) Within all limits
Respondents
•• 1 (0.7 %) In warning zona
         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
      5.63
      2.66
      7.07
     47.23
     12.56
      0.24
      5.07
      1.33
      0.03
   Grand Avg 5.14
               0.94
               0.88
              18.27
               2.74
               0.15
               5.00
               0.00
               0.00
5(4.3 %) Mora than 3 norm. S.D.
 1(0.9 %) Batwaan 2 and 3 norm. S.D
          ; 1O2(88.7 %) Within 1 norm. S.D.
          '                 of known value
      • 7(6.1 %) Batwaan 1 and 2 norm. S.D.

-------
4/20
CRD-LV Performance Evaluation: Uranium-Radium in Water, 6-Dec-1996
Uranium (Natural)
Lab
A
AE
AF
AH
»A*f^P
AK "
AL
AP
AR
'CAtKf
AW
AZ
BA
BC
BG
BG
BG
BH
BK
BM
BN
BO
C
CA
rCC,*i
CE
CG
CJ
CS
CX
D
DB
DE
DI
DO
DR
DT
DZ
E
EB
EL
:'**fl'S
': ~ -x
<^£x> X
ER
Res. 1
4.9
5.3
6.0
4.7

5.4
5.2
6.2
4.6

4.4
4.8
4.5
4.9
5.1
5.3
3.8
5.2
4.6
5.3
6.6
4.2
4.0
5.1

5.6
8.7
5.4
4.5
5.7
5.0
3.9
8.1
5.1
4.1
^'231^3^$:
5.5
5.5
4.9
4.9
4.7


^•f t* V-"*^1^ xf^sW^^*-.
10.3
Res. 2 Res. 3
4.8
5.4
5.2
4.4
pa %ty<"?*j£<&%.^
5.1
4.2
5.0
4.5

4.2
5.1
4.4
4.9
5.2
5.2
3.7
5.4
4.6
5.4
5.4
4.6
4.0
5.3
4.9
5.4
6.2
4.6
*^v^f;-i
5.3
4.5
5.5
4.5
rir'v^
5.5
5.0
4.6
4.8
5.5
5.4
3.7
4.7
4.5
5.6
4.5
5.4
4.0
5.3

5.2
9.7
5.1
4.6
5.8
4.9
3.9
8.2
4.9
4.5

"" "6.4 '
5.6
4.9
5.1
4.6
IjfWl&i^jjjjiy^jtfysff^
;%f«$%%l^|§
##y>J&$£^ ^^S *^;i^f •h^V? * *"
10.1
5.6
6.0
4.9
4.6
5.9
5.1
4.4
8.3
4.8
4.8

4.8
6.1
5.0
5.2
_1£
5?/'-?/^'t '>
•|^>-A^
,X .!- ' .- -.-.'
9.4
• s No data submitted



x &
Exper.
Rnganal
Sigma (R + SR) Average
0.06
0.06
0.53
0.15
Y'!^U7':!,4?~
0.15
0.51
0.60
0.06
vkg»>': „ •• V"S *^<:!
%>{-*- r' -
0.70
0.15
0.10
0.06
0.21
0.10
0.06
0.36
0.06
0.15
1.05
0.61
0.00
0.12
1; ' 0.58 -
0.23
1.91
0.25
0.06
0.10
0.10
0.29
0.10
0.15
0.35
Iptfe^ V-; '***-
0.38
0.32
0.06
0.15
0.10
-r;,V-, r-'V • ' '
•;V>-V '-' ', "
-^ f'^\ ^••'"^
0.47
0.020
0.020
0.197
0.059
•?>!-'54$~ff"
0.059
0.197
0.236
0.020^
"'t- ^T'Vvj,
0.256
0.059
0.039
0.020
0.079
0.039
0.020
0.138
0.020
0.059
0.413
0.236
0.000
0.039
0.197
0.079
0.728
0.098
0.020
0.039
0.039
0.098
0.039
0.059
0.138
„•• ' , -..^ ' ^
0.138
0.118
0.020
0.059
0.039

•

0.177
4.87
5.37
5.80
^4.57 _

5.27
4.63
5.57
4.53

4^70
4.97
4.50
4.87
5.27
5.30
3.73
5.10
4.57
5.43
5.50
4.73
4.00
5.23
/;V^::loW
5.47
8.13
5.13
4.57
5.80
5.00
4.07
8.20
4.93
4.47
">.:,. -.h^y-f^
5.23
5.73
4.93
5.07
4.70
*r* ••',-"-, -/>•' .-!>,.-.,
- i-- '•"* , •','
v ^
9.93
TAG SYMBOLS
Determined
to be an
outlier
Normalized deviation
(grand-avg) (known) Tag
-0.16
0.13
0.38
-0.33
^^w^v^^'-^i
0.07
-0.29
0.25
-0.35
m^^?^'?"- '*$&
-0.25
-0.10
-0.37
-0.16
0.07
0.09
-0.81
-0.02
-0.33
0.17
0.21
-0.23
-0.66
P:06
W-*;^p6::/,^'%'
0.19
1.73
0.00
-0.33
0.38
-0.08
-0.62
1.77
-0.12
-0.39
*jjSKr ^*''',^" '-'^\
0.06
0.34
-0.12
-0.04
_^,,,^.,26_ ^
"sK ;*%>' '->" "'-'- *'"|"
*T ! ~"'^.-'\" • " ">'',C,
..' ^ ^ ' X ' V '" '
2.77
fl a Above
ji s Below
-0.08
0.21
0.46
-0.25
•TOWWWsrap»
'"'': v^l^^iv*^ C.
0.15
-0.21
0.33
-0.27^
^S^T-x-lv-*^
-0.17
-0.02 .
-0.29
-0.08
0.15
0.17
-0.73
0.06
-0.25
0.25
0.29
-0.16
-0.68
0.13
vAOS^'x^J:
0.27
1.81
0.08
-0.25
0.46
0.00
-0.54
1.85
-0.04
•0.31^^ ^
^v *&^^,$j%&
0.13
0.42
-0.04
0.04
^P;,1,7— ,^^
H'.-'---!;^t''; • ., -*'^s$
;-;;"' lr,V'^»'*^-

2.85
control limit
control limit 1

-------
         CRD-LV Performance Evaluation: Uranium-Radium in Water,  6-Dec-1996    8/20
Uranium (Natural)
                                        Exper.    Rng anal              Normalized deviation
Lab     Res. 1     Res. 2      Res. 3     Sigma   (R  + SR)    Average   (grand-avg)  (known) Tag
                                          0.30
                                         *•> **•.-. ^
                                          0.10
                                          0.35
                                          0.25
                                          0.31
                                          0.23
                                          0.38
                                         vt->,
                                            0.079
                                         - . -"• -"• , "/
                                              % ," j"
                                            0.098
                                            0.551
                                            0.059
                      4.00
                      5.60
                      5.37
                      5.83
                      5.23
                      5.93
                     44,40^;,^
                     •  f. oxw,,*^
                     •-"v.Ori
                      4.73
                       4.97
                       5.90
                       4.57
                       -0.66
                        0.27
                        0.13
                        0.40
                        0.06
                        0.46
                    -0.58
                     0.35
                     0.21
                     0.48
                     0.13
                     0.54
                                         X0 -'
                       -0.23
                       ,'; ^
                       -0.16
                        0.44
                       -0.33
                    -0.15
                                      :•%
                      5.3        5.3
                  iss *->vJVCv' ^^ft"* ^  s^"^ C ^^M •• > v.""';"'i:"^S"\Ty'3L.^"-V?''CJ
                                          ^\ *^*  v <*£*%*%**t
                                          0.12      0.039
                                          0.12      0.039
                                   0.00     0.000         5.30      0.09
                                  t:: % -;  - ^^*itT^-sros>iK:;.?; it'^^l
                                  ' 0 ,1     \ "*" w * ^ \ O^- 'X -^ " > *W^<^ J, ^%^t^ f*Vv% - ** ^^ ^ ^^ *^Wi^«
                                   0.60     0.236         4.77      -0.21
                                   0.70     0.276       .  4.93      -0.12
                                   0.06     0.020         4.83      -0.18
                                  Jplf
                    -0.02
                     0.52
                    -0.25
                     0.17
                    HP
                    -0.13
                    -0.04
                    -0.10
                                                          5.07      -0.04
                                                          4.97	^ -0.10 _
                                               '„ "-•' "iW \,\s' " " ','',„ ,!.*'- 'T 'S"«\  <£t*
                                              1-, • ,; "* -',''; "x tW1 ' - '"' i^'; "S^XV v •' '
                                            0.098         4.07      -0.62
                                            0.000         5.00      -0.08
                                            0.04
                                           -0.02
                                                                22.80
                                                                 ^Vo"  -.y *  k -

                                                                   10;2d
                                           -0.54
                                            0.00
                                           ^ , \-"Vs ,S* i"^* "
                                           % s   %;; "- ^" v^ 0
                                           :ioJr-:;'^
0Y^
 r^'-tx^^V}
 S**!,-'*"'Kv.-^,"'' A '•'" %> ~
^'sI^f^M--^ ^f T *\ '-'
                                                                  7.33
                                                                  4.23
                                                                  5.20
                                                                  4.77
                                                                  5.30
                                                                  4.33
                                                                  5-..V \!!«!^ ,
                                                                  •;;%x>;;
                                           0.17      0.059         5.20
                                           •r: -:»: '«•••< .----v^t^^^r^^^-ir^^^
                                                           '"'•*v' '* -f<'v  ^.feM"
0.50
0.197
5.13
                                                                            0.00
0.08
                                                    *
                                                    •
 • a No data submitted
 0 s Insufficient data
                                 TAG SYMBOLS
                          x = Determined to be an outlier
                                ft ^ Above control limit
                                U s Below control limit

-------
6/20 CRD-LV Performance Evaluation: Uranium-Radium in Water, 6-Dec-1996
Uranium (Natural)
Lab
P
PB
PG
PQ
PV
PW
PX
.9
••• ^kiWf 'i
"'' ^B^^H' '-^-i
QQ
QU
QX
QZ

Ml '*!
RD
RF
RG
!'']lii£'
RP
RR
.ifl&
RZ
S
sc
SD
SF
SI
SL
SM
SO
88
SX
sz
i__i v"" v
-T' ' -
TD
.!rat;

9nLr'<
TN"
TQ
U
UE

UN
UP
*<;•"•
"UQ.^
Res. 1 Res. 2
6.7
4.9
5.6
5.1
4.5
3.1
5.4
v 	 4.7 	 _v 	
^^^(Sfefi^^^d
5.5
4.2
1.8
5.0
A^S C'J;^|^4^^

4.6
5.2
..5.0^ _
SiPf^f^filC1 **'l^ J'4
5.2
5.0
=lF:?>Mdp"^^l3
4.5
4.9
5.3
5.3
5.0
4.9
6.3
7.5
7.0
5.2
4.7
4.6
••' v?-i,O<, "''$£;''*'*'•?•*'& y&.& V &%£&%
r ,C?^,! * ~ \< " _ *i\ '' '/
,5-2, ,
'" •" f • •• '," "• •
5.0
4.5

-l>y,\-':, ,**.{. . -;x ^ •
3.4
WN<%^ ^ ^ , s^ 'w s"- /'•s <' , -J ^
*£• \ A -, .^^'^ -- A , - *'^<
4.9
5.2
4.7
5.1
4.7
2.8
5.2
4.1 _ ^
»ifite!fei£si
5.0
5.9
2.3
4.8
^itiSf^Vvv'
^ s *» ^^
4.7
5.1
4.9___
%>r?^o^"-
4.6
4.5
&4Jg5Si«
4.3
4.5
5.9
5.1
4.9
4.8
4.9
5.7
7.0
5.1
4.9
4.6


5.4 "*"'

^»^^

'^lt^~
5.4
5.0
5.0

<:X':.- \*.>;^
4.2
A-; -•'i- ^T-- "*-".. '.'
f -'L^-'"-' '
Res. 3
5.8
4.7
4.6
5.2
5.1
3.5
5.0
4.5
**> 14i7 ' >!-
5.8
4.9
3.3
4.7
'V^i/'/x
^ ^ -'
4.6
4.8
5.0
y^v J ' "
4.8
4.9
«'»*-
%4.7
4.6
4.7
4.8
5.0
4.9
5.8
4.5
6.5
5.0
4.8
4.8
:$^^&wj^**twS."'"'i$>''
4^>V^ -
5.5

e,«::«s>v,\
siTi^;<^
>v.^;"^ '!
5.3
4.9
5.1

-**+•. '" •"•
3.6
*•* j^ '
^
• = No data submitted
0 =


X S
Exper.
Sigma
0.90
0.25
0.55
0.06
0.31
0.35
0.20
0.31
'v\'.-0.26«
0.40
0.85
0.76
0.15
*"' J x.J

0.06
0.21
0.06
""'. /,,, ',;'f.
0.31
0.26
--^- I.8D
0.20
0.21
0.60
0.25
0.06
0.06
0.71
1.51
0.29
0.10
0.10
0.12
'• '*"• \ ^ '•
V #<"-,-!--'
0.06
'As;";w^r";
\ ''*^* -. ' % ^

\ l^ *
0.10
0.06
0.32

-'
0.42


Rnganal
(R + SR) Average
0.354
0.098
0.197
0.020
0.118
0.138
0.079
0.118
,: 0.098
0.158
0.335
0.295
0.059
*

0.020
0.079
0.020

0.118
0.098
0,70>
0.079
0.079
0.236
0.098
0.020
0.020
0.276
0.591
0.098
0.039
0.039
0.039


0.020




0.039
0.020
0.118


0.158


5.80
4.93
4.97
5.13
4.77
3.13
5.20
4.43
%. y- 1460^
5.43
5.00
2.47
	 4.83
;V'W,V ">> ^j^^^l
/ *- s * X *X
4.63
5.03
_ 	 4.9^^
' "• '"" ' "• ^ ^ j *
4.87
4.80
' -X:. 20.1^f;-
4.50
4.67
5.30
5.07
4.97
4.87
5.67
5.90
6.83
5.10
4.80
4.67
* •• "" %"" ^ ^ i1-
• ''•-, -" ' -' :' l'-
	 5.47
<•' '•'• . ~~~'-*' " '"' "
' , -V
•\->
\ 1;
5.30
4.97
4.87

" * \ " ^ V
3.73
'.. .:• .- '^>
,, ,."'-,"*-'
TAG SYMBOLS
Determined to be an
outlier
Normalized deviation
(grand-avg) (known) Tag
0.38
-0.12
-0.10
0.00
-0.21
-1.16
0.04
-0.41
^•i:V&4l4-'J£f
0.17
-0.08
-1.54
-0.18
^?* fe ^K ^'-^W^'
' ' - ** '* '*
-0.29
-0.06
^_-0.10 _^^
*\ ^ ""' •.-.'*' " *,
-0.16
-0.19
>-^«x»v-:r\
-0.37
-0.27
0.09
-0.04
-0.10
-0.16
0.31
0.44
0.98
-0.02
-0.19
-0.27
£* ^1 "• y ?'">'*' ^ ^ ff1" *™s i^^"
^{ -: '.:-O ^^-,
^_0.19_^_
f"\ ^ ^" -" \^
^ % ^ "\" ^ '""\
^ *': *', V-!hX"

0.09
^"' - - ' * •; '_.-
-0.10
-0.16

_;,-v. ? ^,i-z'^ ,-^ f*K
-0.81
\ / ^$X^C* r 5!-.V*x;/ ^ F
' 'i. ^i^~ :'» '"' *'&.,•
tt = Above
U = Below
0.46
-0.04
-0.02
0.08
-0.13
-1.08
0.12
-0.33
fs&j*^ -^s^
0.25
0.00
-1.46
-0.10
"^Sl^^^V^
* *• •• * s
-0.21
0.02
;0.02
"^S^^^i^
-0.08
-0.12
*"8.M™jr ?'•
-0.29
-0.19
0.17
0.04
-0.02
-0.08
0.38
0.52
1.06
0.06
-0.12
-0.19 _^
*? S^^?*'>*1^^^^fSJ^<, 5-^^?
.-jr-^^^'ft^^
0.27 ^^
'^'^^t^^
""_,* ^"">--^s ^ •"< Nv1-^ ^\^ ,;••
,, -,-f-?^ r^r -„;-'" 1
;>• c -'\ .;, -"» f
^0.17 	
-6.02
^-0.08___w _

SVil'-^ ^H^-"!*^^'
-0.73
vl^--^ '* ^^C^^>(?^*>.^vL
,V?'\ l, '^^?^,<"
control limit
control limit

-------

CRD-LV Performance Evaluation: Uranium-Radium in Water, 6-Dec-1996 7
/20
Uranium (Natural)
Exper.
Lab
UZ
fV*AI
VH
VI
J₯
WG
WH
WI
WJ
'•₯* w ****
$Uff%
WR
uWS1
"tm*p^£
•^WX-
X
XA
•^*s A»S •••* +,.
r:xc-A

Res. 1 Res. 2
4.0
^^C^^^^j|S:S
6.6
5.3
	 5.5
5.5
5.2
4.7
^^4.6
	 4.5 ''
^^^JO'^I^^"-^'
fe<^$Jv r^x-?^r
I^^S^P^^i
5.5
5.1
WW*V SV*eW*H^W* 1 ;,*»,» .-A J^,.,v.s s ^ J.w.^'.
^r^^,y.^,*i*V^-

8.8

6.7
5.6
5.4
5.2
5.2
4.6
4.4_
4.4
51v%
"vf'
rv>H
5.0
5.4
V S V.W.S-. f. f
^ 'A* sO"

Average Tag
























2.47
3.13
3.73
3.73
4.00
4.00
4.07
4.07
4.23
4.33
4.43
4.43
4.47
4.47
4.50
4.50
4.53
4.57
4.57
4.57
4.57
4.63 .
4.63
4.63
























Res. 3
12.2
pPf^l^r
5.8
5.3
5.5
5.2
5.4
4.6
_ _^4.4
J.'.^4.4
1 ^^ "i ^ ^ 5A<*
v'-^tV^r
^--^4^
4.8
6.0
.%* \ * v i -.\ ^<•w^ ' ""•

Data
Lab
QX
PW
UP
BG
GN
C
LT
DB
NH
NT
WR
Q
WJ
DO
RZ
BA
AR
JP
CS
BK
AH
WI
RD
AL
Sigma

^ v~ ">*<*-










\



' > ' , ""
4.12
'^V/""
0.49
0.17
0.06
0.17
0.12
0.06
0.12
0.06



0.36
0.46


Rnganal
(R + SR)
2.170
,, ~-\^r^7^sr
0.177
0.059
0.020
0.059
0.039
0.020
0.039
0.020
' "'/''• '71 T't
•;-' / 1/,-!'s?^:'
s •• "" ^ ^ ^X
0.138
0.177
- •• •-'••• ^o ^ ••••% *^;^R-

Average
8.33
'^P^^Ffl
6^37
5.40
5.47
5.30
5.27
4.63
	 4.47 _
^ "^4.43"
':I:-P?5ts';>^
•;^^^|^
"^1%^«S
5.10
5.50
^JS^j^^V*^^^* *» "">
-f-->\;t>v?X^'-
Normalized deviation
(grnnd-avg) (known)
1.85 1.92

0.71 0.79
0.15 0.23
0.19 0.27
0.09 0.17
0.07 0.15
-0.29 -0.21
.-^. :H?^^^.:°~-3L.
-6!41 -0.33
;;|,H;V v,^SiTC%^!l?-5^f^,J
It^i-xVrr^.^^-^^^^^
^\r;l|l;ilfel:|^^Mf
-0.02 0.06
0.21 0.29
™.»,,, ,_ v^
^^


>*> *'*K^'W •*
^-^
sorted by Laboratory Average
Average
























• s No data submitted
0 s
= Insufficient data

X
4.67
4.67
4.70
4.70
4.73
4.73
4.77
4.77
4.77
4.80
4.80
4.83
4.83
4.87
4.87
4.87
4.87
4.87
4.93
4.93
4.93
4.93
4.97
4.97
























Tag
























Lab
SZ
S
EL
AW
BO
JE
PV
NK
JY
SX
RR
QZ
KH
UE
SI
RP
BC
A
PB
K
E
DI
U
SF
Average Tag
























TAG SYMBOLS
= Determined to be an outlier
4.97
4.97
4.97
4.97
4.97
5.00
5.00
5.00
5.03
5.07
5.07
5.07
5.10
5.10
5.10
5.13
5.13
5.13
5.20
5.20
5.20
5.23
5.23
5.23
IT s Above control
U- s Below control
Lab
RG
PG
LF
JK
AZ
QU
LZ
D
RF
L
EB
SD
X
ss
BH
PQ
OS
CJ
PX
OB
NJ
HP
DT
CA
limit
limit

-------
8/20 CRD-LV Performance
Evaluation: Uranium-Radium in Water, 6-Dec-1996
Uranium (Natural)
Data sorted by laboratory Average
Average Tag Lab Average Tag Lab Average Tag
5.27 WH
5.27 BG
5.27 AK
5.30 WG
5.30 TQ
5.30 SC
5.30 NO
5.30 JS
5.30 FN
5.30 BG
5.37 HK
5.37 AE
5.40 VI
5.43 QQ
% responding labs
5.43 BM
5.47 W
5.47 TD
5.47 CE
5.50 XA
5.50 BN
5.57 AP
5.60 GQ
5.67 SL
5.73 DZ
5.80 P
5.80 CX
5.80 AF
5.83 HL
Frequency distribution
5.90
5.90
5.93
6.37
6.83
7.33
8.13
8.20
8.33
9.93
10.33 x
14.40 x
14.50 x
20.13 x
22.80 x


Lab
SM
JN
I
VH
SO
NA
CG
DE
UZ
ER
CC
ID
QM
RX
MX



2Q. 	

10- 	

. 	 	 I. 	
Jr 	
ffl

	





-6 -4 -2 0+2+4
Normalized deviation of the mean from the known value
% responding labs Frequency distribution




a
+6



20' 	

JQ, 	

j 	
It 	
JL
Hill
— .mm — •





-6 -4 -2 0 +2+4
Normalized deviation of the mean from the grand average
• s No data submitted
0 = Insufficient data
TAG SYMBOLS
x ^ Determined to be an outlier
IT s Above control
•11 3 Below control




T*
+6
limit
limit

-------
         CRD-LV Performance Evaluation: Uranium-Radium in Water,  6-Dec-1996    9/20
Radium-226                         Statistical Summary                      151 Participants
The known value of this nuelide is 20.1 pCi/1 with an expected precision of 3.0; the control limits
are 14.9 to 25.3; the warning regions are 14.9 to 16.6 and 23.6 to 25.3
50(33.1 %) Failed to respond ;
8(5.3 %) Outliers *~
1(O.7 %) Out of control
     but not an outlier


         Statistic
                . 85(56.3 %) Within all limits
Respondents
7(4.6 %) 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
     18.84
      3.68
     13.51
     19.51
     -6.28
     -0.34
     19.17
     -4.64
     -0.25
Grand Avg 19.25
             1.80
             3.23
             9.33
            -4.21
            -0.47
            19.33
            -3.81
            -0.43
9(8.9 %) More than 3 norm. S.D. »„
7(6.9 %) Between 2 and 3 norm. S.D.
              9(58.4 %) Within 1 norm. S.D.
                           of known value
     26(25.7 %) Between 1 and 2 norm. S.D.

-------
        CRD-LV Performance Evaluation: Uranium-Radium in Water,  6-Dec-1996
Radium-226
                                                                    Normalized deviation
                                                                    (grnnd-avg)  (known) Tag
              Rnganal
              (R + SR)
                                 Exper.
                                 Siema
                                                            19.70
                                                            17.90
                                                            18.63
                                                            17.63
                                       0.26
                                       0.78
                                       0.36
                                       0.94
                                                             19.83
                                                             19.40
                                                             20.50
                                       0.33
                                       0.08
                                       0.72
    21.5
    20.1
    20.2
                                                                        0.59
                                                                        0.38
                                                                        1.59
                                                                            -1.08
                                                                            -0.87
                                                                            -2.08
                                                                            -0.38
0.158
0.788
0.669
0.315
                            18.23
                            18.60
                            16.50
                                                             16.70
                                                             19.77
                                                             18.17
                                                             19.33
                                                             20.77
                                                             18.53
                                                             20.20
                                                             20.00
                                                             19.60
                                                             18.60
                                                             20.33
                0.295
                0.118
                0.020
                0.394
                0.236
                0.177
                0.000
                0.394
                0.295
                0.591
                0.197
                                                             19.17
                                                             21.43
                                                             18.73
                                                             20.23
                                                             18.63
                                                             19.03
                                                             17.43
                 0.079
                 0.295
                 0.571
                 0.295
                 1.383
                 0.689
                 0.098
                 1.308
                                                                         s Above control limit
                                                                         = Below control limit
       TAG SYMBOLS
x s Determined to be an outlier
No data submitted
 Insufficient data

-------
        CRD-LV Performance Evaluation: Uranium-Radium in Water, 6-Dec-1996  11/20
Radium-226
Lab
Res. 1
                    Exper.    Rng anal             Normalized deviation
Res. 2     Res. 3     Sigma   (R + SR)   Average   (grand-avg) (known) Tag
         15.3
            15.5
            15.4
0.10
0.039
15.40
-2.22
-2.71
                                                0.591
                                                0.374
                                                0.591
                                                1.345
                                                0.197
                                                0.276
                                                    22.67
                                                    20.87
                                                    20.73
                                                    18.60
                                                    18.83
                                                    22.80
                                                           19.83
                                                           15.60
                                                           20.40
                                                           17.50
                                        0.020
                                        0.118
                                        0.492
                                        2.433
 • 3 No data submitted
 0 5 Insufficient data
                              TAG SYMBOLS
                        x = Determined to be an outlier
                                                    1T a Above control limit
                                                        Below control limit

-------
12/20   CRD-LV Performance Evaluation:  Uranium-Radium in Water,  6-Dec-1996
Radium-226

Lab    Res. 1    Res. 2
Res. 3
Exper.
Sigma
Rng anal
(R + SR)
Average
Normalized deviation
(grand-avg)  (known) Tag

-------
CRD-LV Performance Evaluation: Uranium-Radium in Water, 6-Dec-1996 13
Radium-226

Lab Res. 1 Res. 2
VH 18.4 22.2
VI 18.3 19.9
:'wV':V ; :v37iO^:^ 35i0
^WC#'":',,/r -~--:~'9ii-~ ^f% v'5;7v\
,\. ' '•^J " '_xV ' ^\ -\ *• f ' s// ^ •."' "'"^
*'WQ4&,?' "^ ^ ^ >"/'>>>* -, ->
WH 19.2 20.2

Exper. Rng anal Normalized deviation
Res. 3 Sigma (R + SR) Average (grand-avg) (known)
23.8 2.77 1.120 21.47 1.28 0.79
20.0 0.95 0.335 19.40 0.08 -0.40
••'<" 33.0' '2.00 0.788* '> 35.00;- - .' 9i09 :-xl:^;4.8^d5^
~; / v> gil • 2.01 - 0.788.^ v\-A;7.83;:^--- • - -6i5&r?A^v-;s7i08^r
^' ' ' % -s - - * >* "; ^£* \". ^ v'^v^ ^T V < V' ^^^^^{^^l;^,-1^
,<.-;.-!-;--> .-.-•, .• - ' --i1 •' .^A\v.^4'S^*^f^f-s-"' * V'~; ^'^^-"^tf^^f^
20.2 0.58 0.197 19.87 0.35 -0.13
/20


Tag


^*t-T>
it:-k<>:
5"|>v * N*
>^L*^

%*^^y*r\xf£?x>^\^^;'x?^iT^^y^jy^^!^l:»v,^r<%;^Kl'-^l^S??;
^WISV^'V*^ rS-Sfjr.V-*' ^T* *?* •""• x"
WJ 18.8 19.5





X 17.0 16.6
JLA 20.3 23.4
^fps;^^w^. - -

Average Tag
3.77 x
6.53 x
7.83 x
9.57 x
10.60 x
11.53 x
14.87 U
14.93
15.40
15.43
15.60
16.17
16.50
16.70
16.90
17.43
17.50
17.50
17.60
17.63 .
17.70
17.70
17.73
17.77
17.90 '
17.97
• a No data submitted
0 s Insufficient data
l"'t :- 1 - „ , ,, - ,!1l;\ •^;t'\%;>s^*f^CT|"l:-;t«;-; H^;-- ; -'- v^. ^T^rt«>
19.6 0.44 0.158 19.30 0.03 -0.46

'^^P^^^A^\%ii^SWfe^;^'?^^^^^^^^^^^^^^^^^^^*^^^^^^S^^^^^S

^)f i '^L^*-'*i * ,\V '".A^^nV • ^ ^^"'*j»»^^^^^^^^^^^^&«^>4^^^?is^4WS^^^
^i; SJiS^
19.5 1.57 0.571 17.70 -0.90 -1.39
18.2 2.62 1.045 20.63 0.80 0.31
^•^kww, ,** '- •/ --:"-?:^4^^W::^-|/^^^:^4^
Data sorted by Laboratory Average
Lab
AU
MX
we
RX
NO
PV
R
SI
FN
SD
O
TN
BA
BH
I
EP
P
OF
QU
AH
PG
X
ID
UE
AE
GQ
Average Tag Lab
18.03 SS
18.07 SC
18.17 BM
18.23 QQ
18.23 AW
18.37 HL
18.37 GN
18.43 SF
18.47 QZ
18.53 TQ
18.53 C
18.60 K
18.60 CG
18.60 AZ
18.63 EL
18.63 AF
18.73 E
18.80 L
18.83 KH
18.87 DB
19.00 M
19.03 EO
19.03 HP
19.07 U
19.17 DT
19.30 WJ
Average Tag
19.33
19.40
19.40
19.40
19.40
19.43
19.60
19.67
19.70
19.70
19.73
19.77
19.83
19.83
19.87
20.00
20.00
20.10
20.10
20.20
20.23
20.23
20.30
20.30
20.33
20.40
TAG SYMBOLS IT s Above control
x s Determined to be an outlier & s Below control



tf^HtSi

Si^tSss
SS


ii»I'"v

Lab
BN
VI
RF
HK
AL
BC
CE
QM
A
UQ
PW
BK
NT
AK
WH
LZ
CC
SM
RZ
CA
PB
EB
LT
DE
CJ
OB
limit
limit

-------
f
14/20  CRD-LV Performance Evaluation: Uranium-Radium in Water, 6-Dec-1996
  Radium-226
  Average
              Tag
  Data sorted by Laboratory Average
Lab   Average	Tag	  Lab | Average
                   Tag
                      Lab
    20.50
    20.63
    20.63
    20.67
    20.73
    20.77
    20.80
                        AP
                        XA
                        JE
                        SZ
                        JY
                        BO
                        QX
        20.87
        20,87
        20.97
        21.37
        21.40
        21.43
        21.47
        22.07
PX
JX
s
TD
NJ
DZ
VH
CS
22.20
22.67
22.80
22.97
23.43
23.83
27.20
35.00
x
x
RD
JS
KL
UP
VA
Q
ER
W
   % responding labs
                                  Frequency distribution
   10
     responding labs
                    -4      '-20            +2           +4
                       Normalized deviation of the mean from the known value
                                  Frequency distribution
   10
       -6
                  -i           -2     '       6      •      +2           +4
                    Normalized deviation of the mean from the grand average
   • = No data submitted
   0 s Insufficient data
                                     TAG SYMBOLS
                              x s Determined to be an outlier
                                           IT = Above control limit
                                           U = Below control limit

-------
         CRD-LV Performance Evaluation:  Uranium-Radium in Water, 6-Dec-1996  15/20
Radium-228                         Statistical Summary                      151 Participants
The known value of this nuclide is 10.2 pCi/1 with an expected precision of 2.6;  the control limits
are 5.7 to 14.7; the warning regions are 5.7 to 7.2 and 13.2 to 14.7
63(41.7 %) Failed to respond .
8(5.3 %) Outliers	
         Statistic
                - 78(51.7 %) Within all limits
Respondents
2(1.3 %) 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
     10.21
      2.56
      6.54
     25.06
      0.07
      0.00
     10.33
      1.31
      0.05
Grand Avg 10.10
             1.18
             1.39
            11.69
            -0.95
            -0.08
            10.33
             1.31
             0.11
8(9.1 %) More than 3 norm. S.D.
 2(2.3 %) Between 2 and 3 norm. S.D.!
             65(73.9 %) Within 1 norm. S.D.
                           of known value
     13(14.8 %) Between 1 and 2 norm. S.D.

-------
16/20
Radium-228
          _CRD.LV Performance Evaluation: Uranium-Radium in Water,  6-Dec-1996
^'fifKV. £} 1
m^
11.5
8.2
12.7
9.5
f^*'\:-:'
^*.~c • ' ;
y^'&r
12.0
7.3
12.4
9.4
         6.0
         9.3
        10.1
          -"'-*•- •£
 BO
 C
 CA
 CC
 CE
 CG
 CJ
 GMp
 CS
' frif T"*.'
• V2L*.4H-
:0-^
 DB
 DE
 12.9
 10.5
  8.6
 10.0
  9.6
  9.3
 10.0
£!?&:
 10.6
       10.9
       11.3
7.7
9.4
10.5
12.2
10.2
10.2
10.0
9.9
9.2
11.0
f fvwrwn, ^«,\ .s
ite*''*."-. ><
12.0
l^^^l
f^S^S
10.4
11.5
7.8
9.0
10.6
!i.V&»' ' ,' , '
at"t • -
™-s ;*• VJ. \ * * ' ;
10.8
10.4
9.8
11.0
10.5
11.1
10.0
irOv/.
10.1
yfS-s- ;">;'?;• v
^f^£^3 ~^L :
p"'\4 "- '• •'
l^.^.'J'i, '„
10.5
11.9
DZ
;:r::

EB
EL
EO
EP

-s;;"i





10.2
r-*^:«i?1

8.7
10.5
10.6
8.8
'wit '"rv>-"~-t;^r-"
** ^^.f,^-- '.<
s''K»w-:-;>^:--:-;t?k"i-"/ ,
^^JJr^^s^-y-^jyr ,„; ^ ;,.
;fif^^Sv^:;:
• =
[0 =
No
	 ^"8.e""^^


9.1
9.9
10.4
9.0
:~*,--"^.-^7.->--r
v2^A'^s ^-V - .„
^M'-;---;.W"..
t*.^-^^"^^,^,
> =%-^ *r.>'.\ TP-
data submitted
Insufficient
data
                            9.4
                             10.3
                             11.1
                              8.3
                              8.7
 Exper.
 Sigma
  1.18
  0.76
  0.26
  0.87
-.   ''*

  0.67
  0.46
  6.35

  0.71
  0.60
  1.65
  0.79
  0.10

  1.01
  0.21
  0.26

  1,07
 0.15
 0.83
 0.58
 0.46
 1.07
 0.58

 0.98
                                              Rnganal
                                             (R +  SR)
                                                                    Normalized deviation
                                                           Average  (grand-avg)  (known)
                                                                                      Tag
0.26
0.31
^:':Sx;^'
.A
«x* :<•„ 't<\*
•*\^.-*: -
'^:M'-
0.80
0.114
0.136
•^ f
0.114
0.363
                              0.83
                              0.60
                              1.27
                              0.15
                                   TAG SYMBOLS
                                Determined to be an outlier
                                                          11.97
                                                          10.37
                                                           9.53
                                                          10.33
                                                          10.00
                                                           9.87
                                             0.363
                                             0.273
                                             0.523
                                             0.068
                                                                        Above control limit
                                                                        Below control limit

-------
         CRD-LV Performance Evaluation: Uranium-Radium in Water,  6-Dec-1996   17/20
Radium-228
Lab
Res. 1
                     Exper.   Rng anal             Normalized deviation
Res. 2     Res. 3     iSigma   (R +  SR)   Average  (grand-nvg)  (known) Tag
FN
   8.1
                                             8.07
                                                      -1.36
                                           -1.42
                                                   0.023
                                                   0.159
                                                   0.068
                                                   0.409
                                                   0.273
                                                   2.124
                                                   0.591
                                                   0.023
                                                   0.318
                                                   0.114
                                                   0.454
                                                       11.07
                                                       10.93
                                                       11.00
                                                       10.83
                                                       13.07
•*i^^\*31S*1to.M^V * j/"" ^Cj" ^ " •>

 11.8       11.5

 11.7       11.0

      8P3§^
   svwf-^ V-<^ •> s-
   0,-^k V^N •• <  -
   &»$**&&$\^X >\
0.30
0.47
                                                   0.136
                                                   0.204
                                                       11.50
                                                       11.17
                                                 ,0  * 1-*A™"" ^^ ^ " ^^^x \ s
                                                        0.93
                                                        0.71
      0.87
      0.64
•iVX ,""•  CCfS,'-*^5-X •
                                          0.17

                                          1.00
                                          0.25
                                          2.00
                               ^t^'V""^-^ ^S "v "^  "
                               C\V*^v ^''^ \"*₯*% -\s" /C- s
                                14.3       4.86
                                           0.068       11.00       0.60      0.53
                                           -,-.,- ,-^ ^: s^^^v^^V-^S^^?^""
                                                > --^  •»«>«" \V'x\-'C'^>'< - ! ->- £W.. ,\** £•!
                                           0.454       lO.bb      -0.07      -O!l3
                                           0.114        9.57      -0.36      -0.42
                                                                  -0.80      -0.87
                                                                                     -0.78
                                                                                      0.22
 • s No data submitted
 0 s Insufficient data
                      TAG SYMBOLS
               x s Determined to be an outlier
                                                                  ft = Above control limit
                                                                  Ji s Below control limit

-------
  Radium-228
                                                            A         Normalized deviation
                                                            Average   fgranH-nvg)  (known) Tag
                                                                                   0.00
0.204
0.227
                                                  0.227
                                                  0.341
                                                  0.227
                                                  0.204
                                                  0.250
                                                  0.682
                                                  0.114
           10.40
            8.63
           10.13
           10.03
           10.33
                                     0.20
                                     -0.98
                                     0.02
                                     -0.05
                                     0.15
                                                 0.182
                                                 0.136
  s No data submitted
0 s Insufficient data
   TAG SYMBOLS
Determined to be an outlier
                      « Above control limit
                    fl = Below control limit

-------
        CRD-LV Performance Evaluation:  Uranium-Radium in Water, 6-Dec-1996   19/20
Radium-228

Lab    Res. 1
                                    Exper.   Rng anal            Normalized deviation
                 Res. 2    Res. 3     Sigma   (R  +  SR)   Average  (grand-avg)  (known)
                                                                                  Tag
                  11.9      11.4      1.49     0.636       10.80      0.46
                  10.6      10.6      O-O6     °-923       10.63      0.35

WJ
                   9.3       9.4      0.61     0.250        9.70
                     PPSIS IR^Siir^^tt^ T&F- W^lSill^ll
                  10.0       9.3      0.65     0.295        9.97
                         ^Ip^^^i^c ^^^^^^
                           ^•*^^?,j£|^^-'^;--^
                                >.:&*:«
                                                                   -0.27
                                                                            -0.33
                                                                            -0.16
Average
              Tag
                          Data sorted by Laboratory Average
                        Lab | Average	Tag	Lab | Average
                                        Tag
                             Lab
   3.07
   3.50
   4.23
   5.10
   6.77
   7.17
   7.80
   7.87
   8.07
   8.23
   8.30
   8.63
   8.67
   8.67
   8.70
   8.83
   8.90
   8.97
   9.03
   9.03
   9.23
   9.23
   9.30
   9.37
   9.40
   9.40
               x
               x
               X
               X
                        AU
                        QX
                        AP
                        VA
                        X
                        BH
                        SM
                        AE
                        FN
                        GQ
                        AH
                        S
                        81
                        AZ
                        HP
                        EP
                        O
                        OF
                        P
                        GN
                        HL
                        BK
                        UE
                        EB
                        DZ
                        BC
 9.47
 9.53
 9.57
 9.63
 9.63
 9.70
 9.73
 9.77
 9.87
 9.87
 9.97
 9.97
10.00
10.00
10.03
10.13
10.20
10.33
10.33
10.33
10.37
10.40
10.40
10.40
10.47
10.47
RX
CA
NT
TN
SS
WH
HK
EO
QZ
CG
WJ
TQ
NO
CE
SD
sc
RD
SF
CJ
cc
c
RZ
LT
BM
Q
L
10.50
10.53
10.60
10.60
10.63
10.70
10.80
10.80
10.83
10.90
10.93
10.97
10.97
10.97
11.00
11.00
11.00
11.00
11.07
11.13
11.17
11.40
11.40
11.43
11.50
11.57
EL
PB
DB
TD
VI
PW
VH
AL
KH
CS
JY
UP
RF
I
PV
NJ
K
JS
JX
U
MX
AF
A
AW
M
DE
 • = No data submitted
 0 3 Insufficient data
                                    TAG SYMBOLS
                                s Determined to be an outlier
                                                                  tt & Above control limit
                                                                  U s Below control limit

-------
[20/20 CRD-LV Performance
\\
Evaluation: Uranium-Radium in Water, 6-Dec-1996
Radium-228
Data sorted by Laboratory Average
Average Tag Lab Average Tag Lab Average Tag Lab
11.60 SZ
11.83 AK
11.97 BO
% responding labs

10* ----------- — — —

12.10 BA
12.17 UQ
13.07 KL
Frequency distribution
	 • • 	
• •lMil^_ .
„ H-lillmllii.- .
15.27 x ro
17.40 x DT
19 37 x WC
22.00 x QU



_ . _ a

Normalized deviation of the mean from the known value
% responding labs Frequency distribution
ln _!_•-- 	 	
"::::;;:::::::::::::::::.:. jjlil 	

    -8
-4-20            +2            +4
  Normalized deviation of the mean from the grand average
• = No data submitted
0 ^ Insufficient data
                   TAG SYMBOLS
                 Determined to be an outlier
ft = Above control limit
•U = Below control limit

-------