Upload
solomon-casey
View
216
Download
2
Tags:
Embed Size (px)
Citation preview
Laboratory Technical Issues
Presentation to:
KWWOA
April 9, 2014
Department for Environmental ProtectionEnvironmental & Public Protection Cabinet
To Protect and Enhance Kentucky’s Environment
2
Topics• IDC / ODC• MDL• DOC Worksheet• Significant Figures• Rounding• Reporting• Audit Process
3
IDC / ODC
Required by Drinking Water and Wastewater Laboratory Certification
4
Drinking Water Certification Manual• IDC – Chapter IV; Section 7.2.9• MDL – Chapter IV; Section 7.2.11• RLS – Chapter IV; Section 7.2.12
5
Wastewater Certification Manual• Chapter III; Section 7.1
–Demonstration of Capability – the laboratory shall demonstrate their capability to report compliance sample results at or below the required reporting limit (RRL); established by either the Commonwealth of Kentucky or the EPA• IDC/ODC• MDL• RLS
6
Initial Demonstration of Capability (IDC / ODC)
Used to demonstrate that the laboratory and analyst are capable of performing analysis with acceptable precision, accuracy, sensitivity, and specificity pertaining to that particular method
7
IDC / ODC Continued
Analyze 4-mid range concentration laboratory fortified blanks (LFB) on the same or different day.
Acceptance Criteria:• Each of the 4 replicates within 80 – 120% of
mean;• %RSD < 15%
8
Method Detection Limit (MDL)
Defined as the minimum concentration of a substance that can be measured and reported with 99% confidence that the target analyte concentration is greater than zero.
9
MDL Continued• Analyze 7-low level replicates over 2-3 non-
consecutive days;• Calculate the MDL using procedure specified
in 40 CFR 136 Appendix B;
Acceptance Criteria:• Spike level must be with 10 times MDL• MDL < MRL < RRL (Action Limit)
10
Reporting Limit Standard (RLS)
Demonstrate laboratory’s capability to report down to the minimum reporting level (MRL) with known accuracy (70-130% Recovery)
11
RLS Continued• RLS is typical a low calibration standard; or• Stand-alone verification standard
Acceptance Criteria:• RLS Standard < MRL• Calculated %Recovery = 70 - 130%
Detection Limit Terms
• MDL = Method Detection Limit• MRL = Minimum Reporting Limit• RRL = Required Reporting Limit
• RRL = Action Limit = Permit Limit
12
Calibration Curve and RRL - Ideal
13
MDL
MRL
High Std
Concentration
Inst
rum
ent R
espo
nse
Range of Quantita
tion
Est. (J)
RRLCalibration Standards
Calibration Curve and RRL - Issue
14
MDL
MRL
High Std
Concentration
Inst
rum
ent R
espo
nse
Range of Quantita
tion
Est. (J)
RRL
Calibration Standards
15
KY DOC Calculator
DOW provides a DOC Calculator for use by drinking water and wastewater laboratories:
http://water.ky.gov/permitting/Pages/labcert.aspx
Calculator
Significant Figures• Significant figures are critical when reporting scientific data.
1) ALL non-zero numbers (1,2,3,4,5,6,7,8,9) are ALWAYS significant. • The number 123.678 has 6 significant digits.
2) ALL zeroes between non-zero numbers are ALWAYS significant. • The number 103 has 3 significant digits.
3) ALL zeroes which are SIMULTANEOUSLY to the right of the decimal point AND at the end of the number are ALWAYS significant. • The number 111.0 has 4 significant digits.
4) ALL zeroes which are to the left of a written decimal point and are in a number >= 10 are ALWAYS significant.• The number 100.4 has 4 significant digits.
5) Trailing zeroes that do nothing but set a decimal point are not significant• The number 100 has 1 significant digits.
16
Rounding
• Rounding is the last step in calculating results. Only round the final result, not at each step of the calculation. Then follow the following rules:
17
Rounding• Rule 1. Select the digit you want to round and look to the right side of it. If the digit
is 0,1,2,3 or 4, do not change the rounding digit. When rounding whole numbers, all digits that are on the right-hand side of the requested rounding digit will become 0. When rounding numbers involving decimals, all digits to the right of the rounded number are dropped.
18
RoundingRule 2. Select the digit you want to round and look to the right of it. If the digit is 6,7,
8 or 9, your rounding digit rounds up by one number. When rounding whole numbers, all digits that are on the right-hand side of the requested rounding digit will become 0. When rounding numbers involving decimals, all digits to the right of the rounded number are dropped.
19
RoundingRule 3. Select the digit you want to round and look to the right of it. If the digit is 5,
your rounding digit rounds up to the even number. When rounding whole numbers, all digits that are on the right-hand side of the requested rounding digit will become 0. When rounding numbers involving decimals, all digits to the right of the rounded number are dropped.
20
Reporting• Drinking Water
–Hard copy• Must use DOW form
– If Laboratory creates its own forms they must be identical to the DOW form
–Electronic• Must use DOW format (CSV file)
• Wastewater–New DMR Manual is currently being prepared
21
Audit Process• Audit announcement• Day of the audit• Exit• Audit findings• Laboratory response to the findings• DOW accepts/rejects responses• Audit completion certificate issued
22
23
Contact Information
Kentucky Division of Water
200 Fair Oaks; 4th Floor
Frankfort, KY 40601
(502) 564-3410
http://water.ky.gov/permitting/Pages/labcert.aspx