The following table provides a list of interpretive rules and policy statements issued by the NC WW/GW Laboratory Certification program. They are meant to clarify existing legislative rules or to provide guidance where a rule does not exist. Where multiple editions of a single reference source may be approved for reporting purposes and where these approved methods may have conflicting or unclear requirements, the NC WW/GW LC program may adopt a single policy based on a single edition to provide consistency in analytical reporting. Even when citing an alternate reference edition, laboratories must adhere to the NC WW/GW LC policy requirement. 

Policies with an asterisk (* ) beside it notate that this policy could be applicable to Field Laboratory certification, depending on what parameter methods a laboratory is certified for

Parameter Policy
General Quality Control Correlation Coefficient for Linear Calibration Curves *

Electrode Slope/Efficiency Documentation 


Electronic Data Storage, Signature and Reporting Policy *


Factory Set Curve Verification *

  In-line Meter Calibration/Verification *
  Linear Dynamic Range/Linear Calibration Range Verification

Manual Integration

  Required Documentation for Preservation and Hold Time *
  Thermometer Calibration and Verification Policy
   Titrant Standardization *
  Traceability of Chemicals, Reagents, Standards and Materials
  SW-846 Method Implementation
  Weight Verification
  Parameter Specific
Bacteria Quanti-Tray Sealer Check
  Fecal Coliform MF Consumables Testing
  Fecal Coliform Reporting
  Fecal Coliform Sample Bottle Sterility
  Fecal Coliform MF Culture Positive
  Fecal Coliform MF  Reagent Water Testing
  Fecal Sludge Dry Weight Determination Acceptance Criterion
  Fecal Sludge MPN Calculation
BOD/CBOD Flagging QC Failures in BOD Data
  BOD - Checking DO Meter for Drift
  Seed Correction Factor Acceptance Criterion
  Measuring BOD/CBOD Sample Volumes
  Reporting Limit Policy
  Neutralizing Total Residual Chlorine in BOD Samples
CBOD CBOD GGA Standard Acceptance Criterion
Chlorophyll Chlorophyll Sample Collection, Preservation and Holding Time Policy 
Conductivity Automatic Temperature Compensator (ATC) Verification *
Free Available Chlorine FAC Hold Time *
Oil & Grease Oil and Grease Duplicates
Residue TSS Reporting Limit
  TSS Blank Initial Constant Weight
  TS and TDS Reporting Limit 
  TSS, TDS and TS Constant Weight/Drying Time Verification
Turbidity Turbidity Sample Dilution *
  Turbidity Standards *
TRC  Total Residual Chlorine - Sealed Standards in a Field Setting *
VAR Option 3 DO Measurement 
  Option 3 Minimum Sample Volume


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