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•Check

•Parameters

•Rules

•Errors

 

Check for Relative Percent Difference (RPD) values for field duplicate sample results that fall outside Quality Control (QC) limits.

 

 

Check

 

Check name is EarthSoft.DQM.RelativePercentDiffField = Field Duplicate RPD.

 

Parameters

 

This check uses the reportable_result, result_type_code and test_batch_type parameters from Global Parameters. There are eleven other parameters:

•Medium_code_soil – RT_MATRIX.MEDIUM_CODE for DT_SAMPLE.MATRIX_CODE for soil samples. Defaults to Soil.

•Medium_code_water – RT_MATRIX.MEDIUM_CODE for DT_SAMPLE.MATRIX_CODE for water samples. Defaults to Water.

•Multiplier – Multiplier used with detection limit in the FIELD DUPLICATE check to test for results with concentrations > multiplier * detection limit. Defaults to 5.

•MultiplierSoil – Multiplier used with detection limit in the FIELD DUPLICATE check to test soil samples for results with an absolute difference in concentrations > multiplierSoil * detection limit. Defaults to 2.

•AD_multiplier_DL – Multiplier used with the detection limit to define non-detect results = AD_multiplier_DL * detection limit. Defaults to 1. 

•result_type_code - Which RESULT_TYPE to use. Defaults to TRG.

•Rpd_control_limit_other – RPD control limit for other samples. Defaults to 25.

•Rpd_control_limit_soil – RPD control limit for soil samples. Defaults to 35.

•Rpd_control_limit_water – RPD control limit for water samples. Defaults to 20.

•Sample_type_Field_Dup – Defaults to FD.

•Field_dup_detection_limit – Detection limit column to use in the Field RPD calculation (e.g. quantitation_limit or reporting_detection_limit). Defaults to first_non_null_value.

•Compare_to_reported_field_dup - Y/N option to compare the calculated RPD to the reported RPD for Field Duplicate samples. Defaults to “N”.

•Acceptable_variance_field_dup - acceptable variance when comparing the calculated RPD to the reported RPD for Field Duplicate samples. Defaults to “1”.

 

Additional Notes for Parameters:

If compare_to_reported = Y then:

1.DQM will compare the calculated RPD to the laboratory reported value in the qc_rpd column of field duplicate result.

2.If the difference exceeds acceptable_variance, then DQM will create an error in the Errors tab.

 

 

Rules

 

•FIELD DUP RPD > CL - DT_RESULT.RESULT_NUMERIC >= multiplier * Detection Limit and the relative percent difference (RPD) between the results was higher than the upper control limit (RPD_CL)

•FIELD DUP ABS DIFF > DETECTION LIMIT - The absolute difference was greater than the  AD_Multiplier * Detection Limit.

 

 

•FIELD DUPLICATE =

•Review results with DT_SAMPLE.SAMPLE_TYPE_CODE = sample_type_Field_Dup.

•Find the parent sample using DT_SAMPLE.PARENT_SAMPLE_CODE or DT_FIELDQC_BATCH_PARTNER.

•TEST #1:

For both samples, is DT_RESULT.RESULT_NUMERIC >= multiplier * DT_RESULT.REPORTING_DETECTION_LIMIT?

If TRUE, then

Calculate rpd_dup.

•If the MEDIUM_CODE of DT_SAMPLE.MATRIX_CODE = medium_code_soil, then rpd_cl = rpd_control_limit_soil.

•If the MEDIUM_CODE of DT_SAMPLE.MATRIX_CODE = medium_code_water, then rpd_cl = rpd_control_limit_water,

•ELSE rpd_cl = rpd_control_limit_other.

▪If rpd_dup > rpd_cl, then qualify the results.

•TEST #2 (if TEST #1 = FALSE):

If the RT_MATRIX.MEDIUM_CODE of DT_SAMPLE.MATRIX_CODE = medium_code_soil,

·then AD_multiplier = multiplierSoil

·else AD_multiplier = 1.

·ABS_DIFF = absolute difference in the parent and duplicate concentrations = ABS(Parent - Dup).

·Detection_Limit = RT_DQM_CHECK_PARAM.PARAM_CODE = field_dup_detection_limit OR the value in the first column that is not NULL:

·DT_RESULT.REPORTING_DETECTION_LIMIT

·DT_RESULT.QUANTITATION_LIMIT

·DT_RESULT.METHOD_DETECTION_LIMIT

oIf the ABS_DIFF > AD_multiplier * Detection_Limit, then qualify the results.

oWhere detect_flag = N for one of the two values in the field duplicate pair, the Detection Limit * AD_Multiplier_DL is used as the value for the concentration of the non-detect in the ABS_DIFF calculation.

 

Using control limits from RT_DQM_CONTROL_LIMITS is discussed in more detail here.

 

Errors

 

In the Errors tab of the DQM Event Review Form, these errors may be listed:

 

1."One of the required rules for this check is not present in the RT_DQM_RULE table."
If you receive this error, the QAPP can be updated following the How to Update Existing QAPPs documentation page.

2."The variance between the reported RPD ({0}) and the calculated RPD ({1}) exceeded the Acceptable Variance ({2}).
This is an error or warning.

3."Field Duplicate Detection Limit is Not Numeric."
If you receive this error, the check will be skipped.

4."Detect Flag = Y and Field Duplicate Result_Numeric is NULL."
If you receive this error, the check will be skipped.

5."Field Duplicate Parent Sample missing."
If you receive this error, the check is skipped on the field duplicate pair. There may be more than one field duplicate pair in the dataset and if both samples are present, the check will run on the other pair.

6."Detect Flag = Y and Field Duplicate Parent Sample Result_Numeric is NULL."
If you receive this error, the check will be skipped.