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The DQM Check for Field Blank Contamination identifies detected concentrations of target analytes in field blanks. If a detected analyte in a field blank is also contained in an associated sample at a similar level as that in the blank, DQM will qualify the associated sample result.
The check name is EarthSoft.DQM.FieldBlankContamination.
This check uses the following seven check parameters:
1.AmbientBlankSampleType - the sample_type_code used for ambient blanks – defaults to AB.
2.EquipmentBlankSampleType - the sample_type_code used for ambient blanks – defaults to TB.
3.FieldBlankSampleType - the sample_type_code used for field blanks - defaults to FB.
4.Multiplier - used by DQM to determine if result can be qualified as non-detect - defaults to 1 if no value supplied. Must be an integer.
5.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 if no value is supplied. Must be an integer.
6.Flag_blank - if TRUE, the field blanks are also qualified – defaults to TRUE.
7.Normal_sample_types - the sample_type_codes for manual association with field blanks.
Using a value for multiplier from RT_DQM_CONTROL_LIMITS is discussed in more detail here.
This check uses three 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
Additionally, for EQuIS build 7.21.2 and later, this check uses nondetect_detection_limit from Global Parameters.
Notes: •The default value is used if there is no record in RT_DQM_CHECK_PARAM for an input parameter. •The default value is used if the PARAM_VALUE is NULL in RT_DQM_CHECK_PARAM. |
For DQM Version 7.21.1 and earlier versions:
There are three rules:
1.BLANK CONTAMINATION = Qualify the result in the blank sample if a concentration is detected and the FLAG_BLANK parameter = TRUE.
2.RESULT > BLANK * MULTIPLIER = Qualify an associated result if sample result > multiplier * concentration detected in the associated blank.
3.RESULT < BLANK * MULTIPLIER = Qualify an associated result if sample result < multiplier * concentration detected in the associated blank. Assuming the qualifier for this rule = “U”, then this will indicate the result is non-detect. When Completing an Event and saving qualifiers, there is also an option to set DETECTED_YN to "N" for all results with a "U" qualifier.
For DQM Version 7.21.2 and later versions:
In addition to the 3 rules available in 7.21.1 and earlier versions, there are six new rules available:
1.BLANK CONTAMINATION < QL - Contamination detected in the Blank less than the Quantitation Limit
2.BLANK CONTAMINATION >= QL - Contamination detected in the Blank greater than or equal to the Quantitation Limit.
3.RESULT/DF < QL - Associated Result / Dilution Factor < Quantitation Limit.
4.RESULT/DF >= QL OR >= BLANK * MULTIPLIER - For Blank Conc < QL, Associated Result / Dilution Factor >= Quantitation Limit OR >= multiplier * concentration detected in the associated blank.
5.RESULT/DF >= QL & < BLANK * MULTIPLIER - For Blank Conc >= QL, Associated Result / Dilution Factor >= Quantitation 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.
If all 9 blank rules exist in a DQM QAPP, only the 6 new rules available starting in version 7.21.2 will be used by DQM. In order for the 3 rules available prior to 7.21.2 to be used by DQM, only these 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 (by selecting "Manual Associations For Field QC Samples"). If matching samples are found, the process stops.
2.Matching results (with detected concentrations only) by Method, Fraction, CAS_RN and FIELD_SDG. 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 CHAIN_OF_CUSTODY (COC).
Manual Association of samples to Field blanks is discussed here.
Use of Reason Codes with the rules is discussed here.
For DQM Version 7.21.1 and earlier versions:
For Field Blanks
•Review blanks if Flag_blank = TRUE
•Review results with DT_SAMPLE.SAMPLE_TYPE_CODE = AmbientBlankSampleType, EquipmentBlankSampleType, and FieldBlankSampleType
•Qualify a result in a field blank if reportable_result = Y and detect_flag=Yes
The dqm_remark for this exception is: Contamination detected in this blank.
For Associated Samples
•Review results with DT_SAMPLE.SAMPLE_TYPE_CODE = AmbientBlankSampleType, EquipmentBlankSampleType, and FieldBlankSampleType
•Qualify a result in an associated sample if reportable_result = Y and detect_flag=Yes and if sample result > multiplier * concentration detected in the associated blank.
An example dqm_remark for this exception is: [5 > 1 * 4] Sample result > multiplier * concentration detected in the associated blank (sample_id:3281206, test_id:3281223, cas_rn:129-00-0)
•Qualify a result in an associated sample if reportable_result = Y and detect_flag=Yes and if sample result < multiplier * concentration detected in the associated blank.
An example dqm_remark for this exception is: [5 < 1 * 6] Sample result < multiplier * concentration detected in the associated blank (sample_id:3281211, test_id:3281224, cas_rn:7440-66-6)
For DQM Version 7.21.2 and later versions
For Field Blanks
•Review blanks if Flag_blank = TRUE
•Review results with DT_SAMPLE.SAMPLE_TYPE_CODE = AmbientBlankSampleType, EquipmentBlankSampleType, and FieldBlankSampleType
•Qualify a result in a field blank if reportable_result = Y and detect_flag=Yes
1.If BLANK CONTAMINATION < QL - the apply_remark is “Contamination detected in the Blank less than the Quantitation Limit.”
An example dqm_remark for this exception is: “[0.5 < 1] Blank result < quantitation limit in this blank.”
2.BLANK CONTAMINATION >= QL - the apply_remark is “Contamination detected in the Blank greater than or equal to the Quantitation Limit.”
An example dqm_remark for this exception is: “[8 >= 1] Blank result >= quantitation limit in this blank.”
For Associated Samples
•Review results with DT_SAMPLE.SAMPLE_TYPE_CODE = AmbientBlankSampleType, EquipmentBlankSampleType, and FieldBlankSampleType
•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 Limit.”
An example dqm_remark for this exception is: “[0.3 / 1 < 1] Sample result / dilution factor < quantitation 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 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 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 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).”
1.Blank unit error
This check includes an internal unit conversion function, which allows blanks with units for liquids to be compared to results for soil samples. This internal function
includes:
▪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.
The following error message occurs if the units differ and none of the above conversion factors apply:
“Associated result has units ({0}) that do not convert to units of blank result ({1}).” |
For this check to work, a record must be added to RT_UNIT_CONVERSION_FACTOR for that combination.
2.Result Numeric is null
If the RESULT_NUMERIC column is null in the blank or the associated sample for a result, the following error message will be created:
“The RESULT_NUMERIC column is NULL in blank or associated result.”
Copyright © 2023 EarthSoft, Inc • Modified: 31 Mar 2022