ML20210Q812

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Nc State Univ Dept of Environ Health & Safety Radiation Protection Div for Period Jul 1996 - June 1997,Environ Radiation Surveillance Rept
ML20210Q812
Person / Time
Site: North Carolina State University
Issue date: 06/30/1997
From: Douglass J, Harris R
North Carolina State University, RALEIGH, NC
To:
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ML20210Q784 List:
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NUDOCS 9709020164
Download: ML20210Q812 (29)
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/AIJACBMENT A NORTH CAROLINA STATE UNIVERSITY DEPARTMENT OF ENVIRONMENTAL HEALTH AND SAFETY RADIATION PROTECTION DIVISION ENVIRONMENTAL RADIATION SURVEILLANCE REPORT FOR THE PERIOD JULY 1,1996 - JUNE 30,1997 PREPARED BY RALTON J. HARRIS AND JOY L. DOUGLASS f

O M7 R PI)R

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f TABLE OF CONTENTS 1

f PAGE NO.

1. INTRODUCTION 1 Table 1 Environmental Monitoring Programs for the PULSTAR Reactor 2
2. AIR MONITORING 3 Table 2.1 Location c/ Air Monitoring Stations 3 Table 2.2 Aerially Transported Gamma Activity (LLD Values) 4 Figures 2a 2e Airbome Gross Beta Activities 5-9 Table 22 Regulatory Limits, Alert Levels and Background Levels for Airborne Radioactivity 10
3. MILK Table 3.1 11
4. SURFACE WATER Table 4.1 Gross Alpha and Beta Activity in Surface Water 12 Table 4.2 LLD Values for Gamma Emitters in Surface Water 13
5. VEGETATION Table 5.1 Gross Beta Activity in Campus Vegetation 14 4

Table 5.2 LLD Values for Gamma Emitters in Vegetation 15

6. THERMOLUMINESCENT DOSIMETERS 16 Table 6.1 Environmental TLD Exposures 17
7. QUALITY CONTROL INTERCOMPARISON PROGRAM 18 Tables 7.1a 7.1c 19 - 21
8. CONCLUSIONS 22
9. ACKNOWLEDGMENTS 22 APPENDIX 1 23 - 27

l i 1. INTRODUCTION The Environmental Radiation Surveillance Program exists to provide routine measurements of the university environment surrounding the PULSTAR Reactor.

The specific objectives of this program include:

l

1) Providing information that assesses the adequacy of the protection of the university community and the public-at-large;
2) Meeting requirements of regulatory agencies;
3) Verifying radionuclide containment in the reactor facility;
4) Meeting legal liability obligations; and
5) Providing public assurance and acceptance.

During 1995, the Director of the Environmental Health and Safety Center created a committee to assess the environmental monitoring program for the PULSTAR Reactor. This committee issued a detailed report entitled " Report of the Committee to Assess the Environmental Monitoring Program for the North Carolina State PULSTAR Reactor"in which several recommendations were proposed regarding modifications to this program. This information is summarized in Table 1 which has been excerpted from the committee's report.

In brief, the committee recommended the following changes:

1) Discontinue the monthly milk sampling, but instead collect and analyze one milk sample in alternate years. This recommendation has been put into effect.
2) Discontinue the semi-annual vegetation collection, but instead collect and analyze one vegetation sample in alternate years. This recommendation has been put into effect.
3) Change the frequency of air sampling from continuous sampling with filters being collected each week (7-day cycle) to a periodic sampling mode in which air samplers are operated for only one week (7 days) during each 3 month period of the year. This recommendation has been put into effect.
4) Move the air sampler at David Clark Labs to the Environmental Health and Safety Center. This recommendation has been put into effect.
5) Move the air sampler at Withers Hall to North Hall (a student dormitory).

This recommendation could not be accomplished due to restrictions on 1

i

4 I locating equipment on the building which could damage the rubber-lined roof.

l To achieve partial compliance with the committee's recommendations, a TLD station has been located at North Hall to monitor environmental gamma radiation levels.

Table 1:

Environmental Monitoring Programs for the PULSTAR Reactor at North Carolina State University Sample Activity Conducted Previous Current Basis For Measured By Frequency Frequency Measurement Stack Gases Gross Gamma N.E. Continuous Continuous 10 CFR 20 T.S. 6.7.4 Stack Particles Gross Beta N E. Monthly Monthly 10 CFR 20 indiv. Gamma N.E. T.S. 6.7.4 Emitters Water from Gross Beta N E. Prior to Prior to Discharge 10 CFR 20 Reactor Facility Gross Gamma N E. Discharge - Monthly T.S. 6.7.4 Tritium N.E. (- Monthly) City of Raleigh Ordinance Air / Particles at Gross Beta RPD/EHSC Weekly Quarterly 10 CFR 20 5 Campus indiv. Gamma RPDIEHSC Weekly 10 CFR 20 Stations

  • Emitters Air / Dosage at 7 TLD Dosimeter RPD/EHSC Quarterly Quarterly 10 CFR 20 Cainpus Stations +

Surface Water Gross Beta RPD/EHSC Quarterly Quarterly NCSU Rocky Branch Indiv. Gamma RPD/EHSC Quarterly Quarterly NCSU Creek Emitters Vegetation Gross Beta RPD/EHSC Semi-annually Altemate years NCSU NCSU Campus Gamma RPD/EHSC Altemate years NCSU Milk l131 RPDIEHSC Monthly Alternate years NCSU Local Dairy Abbreviations Used in Table:

N.E. = Nuclear Engineering / Reactor Facility; RPD/EHSC = Radiation Protection Division.

  • These 5 stations include:

Withers, Riddick, Broughton, Hill Library and Environmental Health & Safety Center.

+These 7 stations include: the PULSTAR stack, a control station (EHSC) and the 5 air sampling stations, and North Hall.

2 1

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2. AIR MONITORING -(TABLES 2.1,2.2, AND 2.3; FIGURES 2a THROUGH 2e)

Beginning in January 1996, air monitoring frequency has been changed such that air sampling is performed continually.for one week during each of four (4) quarters during the year. The data shows the normal fluctuations in gross beta activity levels expected during the year. Figures 2a through 2e show bar graphs of gross beta activity (fCl/ cubic meter vs. sampling quarters per year). The highest gross beta activity observed was 22.4 fCim'8 at the D.H. Hill Library station during the week of 06/23/97 to 6/30/97. The annual campus average was 13.4 fCim'8 Table 2.2 lists LLD values for several gamma emitters which would be indicative of-fission product activity. No gamma activity due to any of these radionuclides was detected.

l

, . Table 2.3 lists regulatory limits, alert levels, and average background levels for airborne radioactivity.

TABLE 2.1 LOCATION OF AIR MONITORING STATIONS -l ELTE DIRECTION' DISTANCE 2 ELEVATION (meters) (meters)

.BROUGHTON SOUTHWEST 125 -17

  • DAVID CLARK LABS WEST 500 -18 LIBRARY NORTHWEST 192 +11 RIDDICK SOUTHEAST 99 -14 WITHERS- NORTHEAST 82 -6 .-

EH & S CENTER WEST 1230 -3 -

NORTH HALL NORTHEAST 402 -4

' DIRECTION - DIRECTION FROM REACTOR STACK -

2 DISTANCE - DISTANCE FROM REACTOR STACK

~

  • ELEVATION - ELEVATION RELATIVE TO THE TOP OF THE REACTOR STACK
  • The station at David Clark Labs was relocated to the EH & S Center in January 1996, however a TLD monitor is maintained at David Clark Labs for the State of N.C.

. Radiation Protection Division.

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FIGURE 2a AIRBORNE GROSS BETA ACTIVITY ALERT LEVE((=

LLD - 1 fCi/M 3.7 X 500 fCip3 (0 9)185 Bq/M3) 10 Bq/M N.C. STATE UNIVERSITY CAMPUS

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FIGURE 2b 2 AIRBORNE GROSS BETA ACTIVITY ALERT LEVEL =

LLD - 1 fCi/Mg(3.7 500Sq/M X 10+ fCi/M (0 Q)165 Bq/M2)

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Q TABLE 2.3 REGULATORY LIMITS, ALERT LEVELS, AND BACKGROUND LEVELS FOR AIRBORNE RADIOACTIVITY (fCl M *).

REGULATORY - ALERT AVERAGE N.C.

NUCLIDE LIMjI LEVEL BACKGROUND LEVEL GROSS ALPHA 20 10 4 GROSS BETA .1000-- 500 100 Cs 137 5 X 105 10 2 Ce 144 2 X 105 100 0 Ru 106 2 X 105 30 0 1131 1 X 105 10 0 l

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Reference:

Environmental Radiation Surveillance Report 1986-88, State of N.C. Radiation Protection Section 10

4

3. . MILK (TABLE 3.1) l Milk samples are collected in alternate years from the Campus Creamery and the Lake Wheeler

. Road Dalry. Duplicate samples are analyzed for 1131 activity.

No 1131 activity was detected in any of these samples.

. TABLE 3.1.1 131 IN COWS MILK (pClliter 'i 2 o) LLD - 3 pCiliter**

pCi liter' DATE CAMPUS CREAMERY LAKE WHEELER MARCH 1997 s 3.0 s 3.0 l

11 1

4. SURFACE WATER (TABLES 4.1 AND 4.2)

Table 4.1 gives the Dross alpha and beta activities for walor from Rocky Branch at points where it enters (ON) and exits (OFF) the campus. The LLD values for gross alpha and beta activities are - 0.3 pCiliter' and - 0.4 pCiliter', respectively. For groes alpha activity the Alert Levelis 5 pCi litor' and the Regulatory Limit is 15 pCi liter'. For gross beta activity the Alert Levelis 5 pClliter' and the Regulatory Limit is 50 pCilitor'. Samples with gross alpha or beta activities exceeding these Alert Levels would require gamma analysis te identify the radionuclides present. The LLD values in Table 4.2 are for the second quari:r of 1997.

TABLE 4.1 GROSS ALPHA AND BETA ACTIVITY IN SURFACE WATER (pClliter'i 20)

  • LLDa - 0.3 pCiliter' LLDp - 0.4 pCiliter' pCI liter' GROSS GROSS DME LOCATION ALPHA BETA THIRD QUARTER 1996 ON < 0.3 1.0 1 0.3 OFF < 0.3 1.2 1 0.4 FOURTH QUARTER 1996 ON < 0.3 0.7 i 0.3 OFF < 0.3 0.8i0.3 FIRSTQUARTEP '07 ON < 0.3 < 0.4 OFF < 0.3 < 0.4 SECOND QUARTER 1997 ON < 0.3 < 0.4 OFF <0.5 < 0.4

'LLD VALUES ARE DETERMINED QUARTERLY 12 i

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TABLE 4.2 LLD VALUES FOR GAMMA EMITTERS IN SURFACE WATER i

NUCLlDE LLD (oClliterh*

Co-60 0.4 Zn 65 0.7 Cs 137 0.3 Cs 134 0,4 Sr85 0,4 Ru 103 0.3 Ru 106 3.0 l

Nb 95 0.4 Zr 95 0,5

'LLD VALUES ARE FOR THE 2ND QUARTER OF 1997 t

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6. VEGETAIlON (TABLE 5.1 AND 5.2)

Table 5.1 gives gross beta activities for grass samples collected on the NCSU Campus. The reported activities are all below the Alert Level of 20 pCI gram '. Table 5.2 lists LLD values for several gamma emitters. No gamma activity due to any of these radionuclides has been obcerved in campus vegetation. The beta and gamma activities are reported as pCl per gram of green vegetation. Beginning in January of 1996, the vegetation samphng has been revised to be performed .in alternate years.

TABLE 6.1 GROSS BETA ACTIVITY IN CAMPUS VEGETATION

  • LLD - 0.6 pCl g' SAMPLE DATE SAMPLE LOCATION foCl a 1 +2a)

MARCH 1997 NORTH CAMPUS 2.510.1 MARCH 1997 SOUTH CAMPUS 2.6i0.1 MARCH 1997 EAST CAMPUS 2.510,1 MARCH 1997 WEST CAMPUS 2.5

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j TABLE 5.2 LLD VALUES FOR GAMMA EMITTERS IN VEGETATION i t

1 NUCLIDE LLD (pCl gram ')* l Co-60 0,01 i Zn 65 0.02 >

Cs-137 - 0.01 i

Cs 134 - 0,01 Sr85 0.01 -4 Ru 103 0.01 Nb-95 0.01 '

Zr 95 0,02

  • LLD VALUES ARE FOR THE 1ST QUARTER OF 1997 2

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6. THERMOLUMINESCENT DOSlMETERS (TLDs) (TABLE 0.1)

TLD analysis is contracted to Thermo Nutech for determination of ambient gamma exposures.

The dosimeters are LIF and have a manufacturer stated sensitivity of 0.5

  • 0.15 mR (90% 0.L.).

Exposures are integrated over a three month period at each of the five air monitor stations listed in '

Table 2.1 and also at the top of the PULSTAR Reactor stack. During July 1996, m'TLD station was i added to North Hall which is a student dormitory located 402 meters northeast of Burlington Labs.

Also, the TLD station on David Clark Labs was moved to the Environmental Health and Safety ,

Center. A control station is located in Room 107 of the Environmental Safety Center. Table 6.1 gives the data for these seven (7) monitoring locations.

-The observed exposures are those expected to be produced by background radiations in this area of North Carolina. The data of Table 6.1 agrees well with the state wide average exposure rate of

- 18 20 mR per quarter year. There was one unexplained higher than normal exposure reading (72 mR) for D.H. Hill Library during the period 01/17/97 to 04/17/97. TLD readings for the other monitoring stations during this period were all at the expected exposure levels, i

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7. QUALITY GONIRQLINIERGQMEARIEORPRQOEAM The Environmental Radiation Surveillance Laboratory (ERSL) of the Radiation Protection Division has participated in the U.S. DOE Environmental Measurements Laboratory Quality Assurance Division Program (QAP 46) during this reporting period. The objective of this program is to provide laboratories performing environmental radiation measurements with unknowns to test their analytical techniques.

The 'EML value' listed in the Tables 7.1 (a-c) to which the ERSL results are compared is the mean of replicate determinations for each nuclide. The EML uncertainty is the standard error of the mean. All other uncertainties are as reported by the participants.

The controllimit was established from percentiles of historic data distributions (19821992). The evaluation of historic data and the development of the controllimits are presented in DOE report EML 564, The controllimits for QAP 40 were developed from the percentiles of data distributions for the years 1991 1996.

Participants' analytical performance is evaluated based on the historical analytical capabilities for individual analyte / matrix pairs. The criteria for acceptable performance,"A", has been chosen to be between the 15* and 85* percentile of the cumulative normalized distribution, which can be viewed as the middle 70% of all historic measurements. The acceptable with warning criteria,"W",

is between the 5* and 15* percentile and between the 85* and 95* percertile. In other words, the middle 90% of all reported values are acceptable, while the outer 5* 15* (10%) and 85*-95*

preentiles (10%) are in the warning area. The not acceptable criteria, *N", is established at less than the 5* percentile and greater than the 95* percentile, that is, the outer 10% of the historical data.

The following are recommended performance criteria for analysis of environmentallevels of analytes:

Acceptable: Lower Middle Limit s A s Upper Middle Limit Acceptable with Warning: Lower Limit s W < Lower Middle Limit or Upper Middle Limit < W s Upper Limit Not Acceptable: N < Lower Limit or N > Upper Limit Control Limits are reported as the ratio of Reported Value vs. EML Value. The results of the intercomparison studies are given in Table 7.1 (a-c), and are stated in the SI unit becquerel (Bq) as required by the EML reporting protocol.

In addition to the EML Quality Assurance Program, the ERSL conducts an intralaboratory QC program to track the performance of routine radioactivity measurements. The types of calculations employed for this program are shown in an example calculation in Appendix 1.

I 18

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!' TABLE 7.1a GROSS ALPHA & BETA ACTIVITY AIR FILTER INTERCOMPARISON STUDY 01 MARCH 1997 1

The sample consists of one 50 mm diameter simulated filter spiked with a matrix free solution containing a single alpha and a single beta emitting nuclide. The reported values '

and the known values are given in Bqlfilter. The errors are reported as 12 standard a devlations.

'RCSU ENVIRONMENTAL LABORATORY RESULTS Radio-

  • Reported ' Reported EML EML Error _ Reported Evaluation nuclide Value Error Value EML Gross Alpha 1.00 0.05 0.96 0.05 1.042 A 4 Gross Beta 0.46 0.03 0.45 0.03 1.022 A Evaluation: A = Acceptable, W = Acceptable with Warning, N = Not Acceptable 1
QAP 46 Statistical Summarv
Radlo. EML EML Mean Medlan Std. Dev. No. Of Reported

, nuclide Value Error Values Gross Alpha 0.96 0.05 1.064 1.036 0.170 72

Gross Beta 0.45 0.03 1.141 1.133 0.261 69

! QAP 46 Con _ttol Limits by Matrix Radio nuclide Lower Limit Lower Middle Upper Middle Upper Limit Limit Limit Gross Alpha 0.66 0.89 1,48 1.77

! Gross Beta 0.45 0.80 1.34 1.67 Controllimits are reported as: the ratio of Reported Value vs. EML Va!ue t

19

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1 TABLE 7 ib 2

MULTINUCLIDE AIR FILTER INTERCOMPARISON STUDY

, 01 MARCH 1997 i

The sample consists of one 7 cm diameter glass fiber filter which has been spiked with 0.10 gram of solution and dried. The reported values and the known values are given in Bqlfilter. The errors are reported as 12 standard deviations.

'NOSU ENVIRONMENTAL LABORATORY RESULTS

Radio. ' Reported
  • Reported EML EML Error Reported Evaluation nuclide Value Error Value EML ,

15.380 2.100 15.700 1.000 0.980 A Ce144 11.320 0.490 10.810 1.000 1.047 A CoS7 5.220 0.560 5.010 0.300 1.042 A Co60 12.760 0.730 10.880 1.000 1.173 W '

Cs134 8.820 0.600 8.700 0.800 1.014 A

} Cs137 8.540 0.560 7.620 0.600 1.121 W Mn54 13.040 1.120 12.330 1.000 1.058 A l Sb125 Evaluation: A = Acceptable, W = Acceptable with Warning, N = Not Acceptable QAP 46 Sigilailcal Summary Radio. EML EML Mean Median Std. Dev. No. Of Reported nuclide Value Error Values 1

Ce144 15.700 1.000 0.972 0.964 0.127 80

CoS7 10.810 1.000 1.023 1.008 0.098 81
Co60 5.010 0.300 1.040 1.038 0.075 85 Cs134 10.880 1.000 1.026 1.029 0.090 89 Cs137 8.700 0.800 1.051 1.034 0.108 94 Mn54 7.620 0.600 1.072 1.072 0.111 83
Sb125 12.330 1.000 1.089 1.079 0.114 85 1

QAP 46 Control Limits by Mattix c

I Radio.nuclide Lower Limit Lower Middle Upper Middle Upper Limit Limit Limit a

Ce144 0.58 0.66 1.10 1.26 Co67 0.62 0.69 1.10 1.28 Co60 0.75-- 0.82 1.10 1.27 i Cs134 0.73 0.81 1.11 1.22 Cs137 0.72 0.82 1.11 1.33 4

Mn54 0.76 0.83 1.11 1.32 ,

Sb125 0.58 0.81 1.14 1.36 Control limits are reported as: the ratio of Reported Value vs. EML Value 20 4

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l TABLE 7.1c MULTINUCLIDE WATER SAMPLE INTERCOMPARISON STUDY 01 MARCH 1997 t

The sample consists of a spiked,455 mi aliquot of acidified water (~1 N hcl). The reported -

values and the known values are given in Bq/Ilter. The errors are reported as 12 standard deviations.

'NCSU ENVIRONMENTAL LABORATORY REEULIE 4

Radio-

  • Reported
  • Reported EML EML Error _ Reported Evaluation nuclide Value Error Value EML Co60 95.79 2.57 90.85 1.15 1.054 0 '

Cs134 22.71 1.79 20.55 0.31 1.105 0 ,

Cs137 71.02 2.12 69.78 1.23 1.018 0 Mn54 21.62 1.76 20.85 0.31 1.037 0 0 Due to laboratory Instrument problems, these data were not available to submit for EML evaluation by the deadline. All reported values are within the acceptable range defined by the control limits.

QAP 46 Statistical SummAIX Radio. EML EML Mean Median Std. Dev. No. Of Reported nuclide Value Error Values i Co60- 90.850 1.150 1.067 1.070 0.049 95 Cs134 - 20.550 0.310 1.057 1.068 0.071 28  ;

Cs137 69.780 1.230 1.112 1.113 0.064 101 Mn54 20.850 0.310 1.113 1.122 0.067 92 QAP 46 Control Limits by Matrix Radio nuclide Lower Limit Lower Middle Upper Middle Upper Limit Limit Limit Co60 0.80 0.90 1.13 1.18 Cs134 0.89 0.90 1.16 1.25 Cs137 0.80 0.90 1.18 1.27 Mn54 0.80 0.90 1.16 1.22 Control limits are reported as: the ratio of Reported Value vs. EML Value .

21

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i CONCLUSIONS i

l - The data obtained during this period do not show any fission product activities. The observed environmental radioactivity is due primarily to radon progeny, primordial radionuclides (e.g. K-40)

!-- and those radionuclides (e.g., Be 7) which originate in the upper atmosphere as the result of i j cosmic ray interactions. These facts justify the conclusion that the PULSTAR Reactor facility  ;

j continues to operate safely and does not telease fission product materials into the environment,

,i l 9. ACKNOWLEDGMENTS The graphs and arrangement of this report are available due to the assistance of Ms. Joy L I

Douglass, i l-i l

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9 o . l APPENDIX 1 i The following example calculation gives a set of data, the mean value, the experimental sigma, and the range. Those statistics provide measures of the central tendency and dispersion of the data.

The normalized range is computed by first finding mean range, R, the control limit, CL, and the standard error of the range, a n. The normalized range measures the dispersion of the data (precision) in such a form that control charts may be used. Control charts allow one to readily compare past analytical performance with present performance. In the example, the normalized range equals 0.3 which is less than 3 which is the upper controllevel. The precision of the results is acceptable.

The normalized deviation is calculated by computing the deviation and the standard error of the mean, om. The normalized deviation allows one to measure central tendency (accuracy) readily through the use of control charts. Trends in analytical accuracy can be determined in this manner.

For this exemple, the normalized deviation is 0.7 which falls between +2 and 2 which are the upper and lower warning levels. The accuracy of the data is acceptable. Any bias in methodology or instrumentation may be indicated by these results.

4 23'

O

  • EXAMPLE CALCULATIONS Experimental Data:

Known value = p = 3273 pCi 8H/ liter on September 24,1974 Expected laboratory precision = a = 357 pCVliter Samoto Result X, 3000 pCVliter X, 3000 pCVliter X3 3240 pCVliter Mean = Y b X, 9360 Y = = = 3120 pCVliter 3

N whers N = number of results = 3 Experimental vigma = s

( X,) "

s = ( X, ) * -

4. N h N-1 (3060) 3 + (3060) 8 + (32 4 0) 8- (3060 +30 60 +32 4 0) 8

=

3 s

s = 103,9 pCl/ liter Range = r r a lmaximum result minimum resultI r = 0240 - 306d r = 180 pCVliter 24

e Range Analysis (RNO ANLY)*

Mean range = R R = doi where d," = 1.693 for N = 3

=

(1.693)(357)

R = 604.4 pCl/ liter -

Controllim!t = CL CL e R + 30,

= D.R where D " = 2.575 for N = 3 m

(2.575)(604.4)

CL = 1556 pCl/ liter l Standard error of the range =

  • on on = (R + 3on R) + 3

= (D.R . R) + 3

=

(1550 604.4) + 3 on = 317.2 pCl/ liter Let Range = r = wR + xon = 180 pCl/ liter Define normalized range = w + x for r > R, w = 1 then r a wR + xon = R + xon rR or x=-

on r-R therefore w+x=1+x=1+

on

'Rosentein, M., and A. S. Goldin, " Statistical Techniques for Quality Control of Environmental Radioassay,"

AOCS Rooort Stat-1. U.S. Department of Health Education and Welfare, PHS, November 1964.

"From table " Factors for Computing Control Limits," Handbook of Tables for Probability and Statistics. 2Dd Editiori, The Chemical Rubber Co., Cleveland, Ohio,1968, p. 454.

I 25

= _

0 o .

l for r 5 R, x = 0 l then r = wR + xon = wR or w=

l R r

therefore w + x = w + 0 = -

R since r < R. (180 < 604.4) 180 W+x=-

604.4 ,

t W + x = 0.30 1

Normalized deviation of the'mean from the known value = ND Deviation of mean from the known value = D D=xp

= 3120 3273 0 = -153 pCl/ liter Standard error of the mean = 0 O

o=

vN l

357

=

v'3 c = 206.1 pCl/ liter D

ND a on

+153

=

206,1 ND = -0.7 i

Controllimit = CL L

CL = (p i 30.)

l 26-

. . - , - - - , .--.,-w< ,ww,- . , , , ,,-+,-,n,-- r--- y, , ,-~r.-r -

-r - , - -,-w,re ,, **t a--' u-w-<---1wv-

o s

Warning limit = WL WL = (p i 20m)

Experimental sigma (alllaboratories) = s,

( x ,)

  • x,*-

i1 N h N-1 162639133 - ( 9345)8 h 14

  • = 149 pCVliter Grand Average = GA Xs

=

GA ~

N 49345 15 GA = 3290 pCl/ liter Normalized deviation from the grand average = ND' Deviation of the mean from the grand average = D' D' = E GA

= 3120 - 3290 D' = 170 pCVliter ND' = --

0=

170 e

206.1 N D' = - 0. 8 27

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