Trip Blank Contamination Check

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Trip Blank Contamination Check

Check

Parameters

Rules

Exceptions

Errors

 

The DQM Check for Trip Blank Contamination identifies detected concentrations of target analytes in trip blanks. If a detected analyte in a trip blank is also contained in an associated sample at a similar level as that in the blank, DQM will qualify the associated sample result.

 

Check

 

The check name is EarthSoft.DQM.TripBlankContamination.

 

Parameters

 

This check uses four Global Parameters:

1.reportable_result DT_RESULT.REPORTABLE_RESULT values to include in DQM datasets

2.result_type_code DT_RESULT.RESULT_TYPE_CODE to include in DQM datasets

3.test_type_batch – AT_TEST_BATCH_ASSIGN.TEST_BATCH_TYPE to include in DQM dataset

4.nondetect_detection_limit – Identifies which detection limit column from DT_RESULT to populate DT_RESULT.RESULT_VALUE

 

Note: Quantitation/Detection Limit = The detection limit column from DT_RESULT set in the global parameter nondetect_detection_limit.

 

This check uses the following seven parameters (listed below). None of these parameters allow for method-specific PARAM_VALUEs. However, the common_lab_multiplier allows for input of analyte-specific PARAM_VALUEs for each CAS_RN.  Additionally, matrix-specific AND analyte- or method-specific multipliers can be used by populating RT_DQM_CONTROL_LIMITS.BLANK_MULTIPLIER. See below for additional information on the order of what {MULTIPLIER} is used.

1.AmbientBlankSampleType The SAMPLE_TYPE_CODE used for ambient blanks; defaults to "AB".

2.TripBlankSampleType The SAMPLE_TYPE_CODE used for ambient blanks; defaults to "TB".

3.Multiplier Used by DQM to determine if a result can be qualified as non-detect; defaults to 1. Must be an integer.

4.Common_lab_multiplier Used by DQM to determine if a result identified as a common laboratory contaminant can be qualified as non-detect; depends on CAS_RN field being populated, and defaults to 2. Must be an integer.

5.Flag_blank If TRUE, the trip blanks are also qualified; defaults to "TRUE".

6.Normal_sample_types The SAMPLE_TYPE_CODEs used for standard association of trip blanks; defaults to “N”.

7.result_type_code – the result type(s) of the results to be included in this check. The default value is “TRG”.

 

Notes:

Default parameter values listed above refer to the value provided in the DQM Starter QAPP.xlsx.

The RT_DQM_CONTROL_LIMITS.METHOD_ANALYTE_GROUP_CODE for the BLANK_MULTIPLIER must be null or it must be a dataset selection on the Start Event Form.

 

Rules

 

There are six rules:

1.BLANK CONTAMINATION < QL Contamination detected in the Blank less than the Quantitation/Detection Limit.

2.BLANK CONTAMINATION >= QL Contamination detected in the Blank greater than or equal to the Quantitation/Detection Limit.

3.RESULT/DF < QL Associated Result / Dilution Factor < Quantitation/Detection Limit.

4.RESULT/DF >= QL OR >= BLANK * {MULTIPLIER} For Blank Conc < QL, Associated Result / Dilution Factor >= Quantitation/Detection Limit OR >= multiplier * concentration detected in the associated blank.

5.RESULT/DF >= QL & < BLANK * {MULTIPLIER} For Blank Conc >= QL, Associated Result / Dilution Factor >= Quantitation/Detection Limit AND < multiplier * concentration detected in the associated blank.

6.RESULT/DF >= BLANK * {MULTIPLIER} For Blank Conc >= QL, Associated Result / Dilution Factor >= multiplier * concentration detected in the associated blank.

 

There were 3 different blank rules available in the 7.21.1 Build and earlier builds (BLANK CONTAMINATION, RESULT > BLANK * MULTIPLIER, RESULT < BLANK * MULTIPLIER). If those 3 rules exist in a DQM QAPP, along with the 6 rules listed above, then only the 6 above rules (available starting in the 7.21.2 Build) will be used by DQM. For the 3 rules available in the 7.21.1 Build (and earlier builds) to be used by DQM, then only those 3 rules should be included in the DQM QAPP.

 

DQM Associated results are found by:

1.Matching results (with detected concentrations only) using DT_FIELDQC_BATCH_PARTNER and Method, Fraction, CAS_RN. If matching samples are found, the process stops. DT_FIELDQC_BATCH_PARTNER is populated by selecting "Manual Associations For Field QC Samples" when creating a DQM Event or Collect/EDGE/EDP, see Field Batch Partner for additional information.

2.Matching results (with detected concentrations only) by Method, Fraction, CAS_RN and CHAIN_OF_CUSTODY (COC). If matching samples are found, the process stops.

3.If no matching results are found in Step 1, results (with detected concentrations only) are matched by Method, Fraction, CAS_RN and FIELD_SDG.

 

Manual Association of samples to Trip blanks is discussed here.

 

Use of Reason Codes with the rules is discussed here.

 

Exceptions

 

For Lab Blanks:

Review blanks if FLAG_BLANK = TRUE

Review results with DT_SAMPLE.SAMPLE_TYPE_CODE = AmbientBlankSampleType and TripBlankSampleType

Qualify a result in a lab blank if REPORTABLE_RESULT = Y and DETECT_FLAG = Yes according to the following:

1.If BLANK CONTAMINATION < QL The APPLY_REMARK is “Contamination detected in the Blank less than the Quantitation/Detection Limit.”
An example DQM_REMARK for this exception is: “[0.5 < 1] Blank result < Quantitation/Detection limit in this blank.”

2.BLANK CONTAMINATION >= QL The APPLY_REMARK is “Contamination detected in the Blank greater than or equal to the Quantitation/Detection Limit.”
An example DQM_REMARK for this exception is: “[8 >= 1] Blank result >= Quantitation/Detection limit in this blank.”

 

For Associated Samples:

Review results with DT_SAMPLE.SAMPLE_TYPE_CODE =Normal_sample_types.

{MULTIPLIER} = if an analyte-specific match is found for common_lab_multiplier, then that value is used. If no match is found, the check looks for matches in RT_DQM_CONTROL_LIMITS and uses the BLANK_MULTIPLIER value. Using a multiplier from RT_DQM_CONTROL_LIMITS is discussed in more detail here. If no match is found for either, DQM defaults to the Multiplier parameter value.

Qualify a result in an associated sample if REPORTABLE_RESULT = Y and DETECT_FLAG = Yes according to the following:

1.RESULT/DF < QL The APPLY_REMARK is “Associated Result from: Associated Result / Dilution Factor < Quantitation/Detection Limit.”
An example DQM_REMARK for this exception is: “[0.3 / 1 < 1] Sample result / dilution factor < Quantitation/Detection limit in this associated blank: (sys_sample_code:AQ_SAMPLE1_RC_TB, analytic_method:SW6010, cas_rn:7440-28-0).”

2.RESULT/DF >= QL OR >= BLANK * {MULTIPLIER} – The APPLY_REMARK is “Associated Result from: For Blank Conc < QL, Associated Result / Dilution Factor >= Quantitation/Detection Limit OR >= multiplier * concentration detected in the associated blank.”
An example DQM_REMARK for this exception is: “[5 / 1 >= 1 * 0.5] Sample result / dilution factor >= multiplier * concentration detected in this associated blank: (sys_sample_code:AQ_SAMPLE1_RC_TB, analytic_method:SW6010, cas_rn:7440-28-0)”

3.RESULT/DF >= QL & < BLANK * {MULTIPLIER} – The APPLY_REMARK is  “Associated Result from: For Blank Conc >= QL, Associated Result / Dilution Factor >= Quantitation/Detection Limit AND < multiplier * concentration detected in the associated blank.
An example DQM_REMARK for this exception is: “[10 / 1 >= 1] AND [10 / 1 < 2 * 8] Sample result / dilution factor >= Quantitation/Detection limit AND < multiplier * concentration detected in this associated blank:(sys_sample_code:AQ_SAMPLE1_RC_TB, analytic_method:SW6010, cas_rn:7782-49-2).”

4.RESULT/DF >= BLANK * {MULTIPLIER} – The APPLY_REMARK is “Associated Result from: For Blank Conc >= QL, Associated Result / Dilution Factor >= multiplier * concentration detected in the associated blank.
An example DQM_REMARK for this exception is: “[10 / 1 >= 1 * 8] Sample result / dilution factor >= multiplier * concentration detected in this associated blank: (sys_sample_code:AQ_SAMPLE1_RC_TB, analytic_method:SW6010, cas_rn:7782-49-2).”

If the Associated Sample's Reason Code ends with a "+" then the parent QA Sample Exception's Reason Code will be appended to the Associated Sample's Reason Code using an underscore and the "+" removed. (For example: when the rt_dqm_rule.reason_code = "TBA1+" and the QA Sample Reason Code is "TBH", then the associated result reason code becomes "TBA1_TBH".)

If the Associated Sample's Reason Code in rt_dqm_rule.reason_code = "+", then the QA Sample's Reason Code is used instead.

 

Errors

 

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

1.“Associated result has units ({0}) that do not convert to units of blank result ({1}).”
This check includes an internal unit conversion function which includes the below conversions. This allows blanks with liquid  units to be compared to results for soil samples. This error message occurs if the units differ and none of the below conversion factors apply.

ug/L to mg/kg

ug/L to ug/kg

mg/L to mg/kg

mg/L to ug/kg

Any combination of units found in RT_UNIT_CONVERSION_FACTOR will also be used.

For this check to work, a record must be added to RT_UNIT_CONVERSION_FACTOR for that combination.

2."The Quantitation/Detection Limit is missing for (sys_sample_code:{0}, analytic_method:{1}, cas_rn:{2})"
When this error is present, this check will be skipped for this result and the associated results.

3."Blank Result's Detect Flag = Y and Result_Numeric is NULL or Non-Numeric for (sys_sample_code:{0}, analytic_method:{1}, cas_rn:{2})"
When this error is present, this check will be skipped for this result and the associated results.

4."Associated Result's Detect Flag = Y and Result_Numeric is NULL or Non-Numeric for (sys_sample_code:{0}, analytic_method:{1}, cas_rn:{2})"
When this error is present, this check will be skipped for this individual associated result.

5."The DILUTION_FACTOR column is NULL or not numeric at (sys_sample_code:{0}, analytic_method:{1}, cas_rn:{2})"
When this error is present, this check will be skipped for this individual associated result.