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Qualifiers
April 02, 2025
AQS Reference Table
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This table has a "Still Active" column. If this code can be used to submit new data, this is set to YES. If this code is no longer allowed on new data, but the code may be attached to older data, it is set to NO.
Qualifier Code | Qualifier Description | Qualifier Type | Qaulifier Type Code | Still Active | Legacy Code |
---|---|---|---|---|---|
RA | African Dust. | Request Exclusion | REQEXC | YES | |
RB | Asian Dust. | Request Exclusion | REQEXC | YES | |
RC | Chemical Spills & Industrial Accidents. | Request Exclusion | REQEXC | YES | |
RD | Cleanup After a Major Disaster. | Request Exclusion | REQEXC | YES | |
RE | Demolition. | Request Exclusion | REQEXC | YES | |
RF | Fire - Canadian. | Request Exclusion | REQEXC | YES | |
RG | Fire - Mexico/Central America. | Request Exclusion | REQEXC | YES | |
RH | Fireworks. | Request Exclusion | REQEXC | YES | |
RI | High Pollen Count. | Request Exclusion | REQEXC | YES | |
RJ | High Winds. | Request Exclusion | REQEXC | YES | |
RK | Infrequent Large Gatherings. | Request Exclusion | REQEXC | YES | |
RL | Other. | Request Exclusion | REQEXC | YES | |
RM | Prescribed Fire. | Request Exclusion | REQEXC | YES | |
RN | Seismic Activity. | Request Exclusion | REQEXC | YES | |
RO | Stratospheric Ozone Intrusion. | Request Exclusion | REQEXC | YES | |
RP | Structural Fire. | Request Exclusion | REQEXC | YES | |
RQ | Terrorist Act. | Request Exclusion | REQEXC | YES | |
RR | Unique Traffic Disruption. | Request Exclusion | REQEXC | YES | |
RS | Volcanic Eruptions. | Request Exclusion | REQEXC | YES | |
RT | Wildfire-U. S. | Request Exclusion | REQEXC | YES | |
1 | Deviation from a CFR/Critical Criteria Requirement. | Quality Assurance Qualifier | QA | YES | |
1V | Data reviewed and validated. | Quality Assurance Qualifier | QA | YES | |
2 | Operational Deviation. | Quality Assurance Qualifier | QA | YES | |
3 | Field Issue. | Quality Assurance Qualifier | QA | YES | |
4 | Lab Issue. | Quality Assurance Qualifier | QA | YES | |
5 | Outlier. | Quality Assurance Qualifier | QA | YES | |
6 | QAPP Issue. | Quality Assurance Qualifier | QA | YES | |
7 | Below Lowest Calibration Level. | Quality Assurance Qualifier | QA | YES | |
9 | Negative value detected - zero reported. | Quality Assurance Qualifier | QA | YES | |
CB | Values have been Blank Corrected. | Quality Assurance Qualifier | QA | YES | |
CC | Clean Canister Residue. | Quality Assurance Qualifier | QA | YES | |
CF | Canister Bias: NATTS/UATMP Data for compounds that have failed certification for the canister. | Quality Assurance Qualifier | QA | YES | |
CL | Surrogate Recoveries Outside Control Limits. | Quality Assurance Qualifier | QA | YES | |
DI | Sample was diluted for analysis. | Quality Assurance Qualifier | QA | YES | |
DN | DNPH peak less than NATTS TAD requirement, reported value should be considered an estimate. | Quality Assurance Qualifier | QA | YES | |
EH | Estimated; Exceeds Upper Range. | Quality Assurance Qualifier | QA | YES | |
FB | Field Blank Value Above Acceptable Limit. | Quality Assurance Qualifier | QA | YES | |
FX | Filter Integrity Issue. | Quality Assurance Qualifier | QA | YES | |
HT | Sample pick-up hold time exceeded. | Quality Assurance Qualifier | QA | YES | |
LB | Lab blank value above acceptable limit. | Quality Assurance Qualifier | QA | YES | |
LJ | Identification Of Analyte Is Acceptable; Reported Value Is An Estimate. | Quality Assurance Qualifier | QA | YES | |
LK | Analyte Identified; Reported Value May Be Biased High. | Quality Assurance Qualifier | QA | YES | |
LL | Analyte Identified; Reported Value May Be Biased Low. | Quality Assurance Qualifier | QA | YES | |
MD | Value less than MDL. | Quality Assurance Qualifier | QA | YES | |
MS | Value reported is 1/2 MDL substituted. | Quality Assurance Qualifier | QA | YES | |
MX | Matrix Effect. | Quality Assurance Qualifier | QA | YES | |
ND | No Value Detected, Zero Reported. | Quality Assurance Qualifier | QA | YES | |
NS | Influenced by nearby source. | Quality Assurance Qualifier | QA | YES | |
QP | Pressure Sensor Questionable. | Quality Assurance Qualifier | QA | YES | |
QT | Temperature Sensor Questionable. | Quality Assurance Qualifier | QA | YES | |
QX | Does not meet QC criteria. | Quality Assurance Qualifier | QA | YES | |
SB | Sampler Bias: NATTS/UATMP Data for compounds that have failed certification for the sampler. | Quality Assurance Qualifier | QA | YES | |
SP | NATTS/UATMP data with Spike Recovery outside acceptance limits. | Quality Assurance Qualifier | QA | YES | |
SQ | Values Between SQL and MDL. | Quality Assurance Qualifier | QA | YES | |
SS | Value substituted from secondary monitor. | Quality Assurance Qualifier | QA | YES | |
SX | Does Not Meet Siting Criteria. | Quality Assurance Qualifier | QA | YES | |
TB | Trip Blank Value Above Acceptable Limit. | Quality Assurance Qualifier | QA | YES | |
TT | Transport Temperaure is Out of Specs. | Quality Assurance Qualifier | QA | YES | |
V | Validated Value. | Quality Assurance Qualifier | QA | YES | |
VB | Value below normal; no reason to invalidate. | Quality Assurance Qualifier | QA | YES | |
W | Flow Rate Average out of Spec. | Quality Assurance Qualifier | QA | YES | |
X | Filter Temperature Difference or Average out of Spec. | Quality Assurance Qualifier | QA | YES | |
XC | Canister certification expired | Quality Assurance Qualifier | QA | YES | |
XS | Traceable to a Standard Reference Photometer (SRP) with the Hearn (1961) 308.32 atm-1 cm-1 Ozone Cross-Section Value. | Quality Assurance Qualifier | QA | YES | |
Y | Elapsed Sample Time out of Spec. | Quality Assurance Qualifier | QA | YES | |
AA | Sample Pressure out of Limits. | Null Data Qualifier | NULL | YES | 9967 |
AB | Technician Unavaliable. | Null Data Qualifier | NULL | YES | 9968 |
AC | Construction/Repairs in Area. | Null Data Qualifier | NULL | YES | 9969 |
AD | Shelter Storm Damage. | Null Data Qualifier | NULL | YES | 9970 |
AE | Shelter Temperature Outside Limits. | Null Data Qualifier | NULL | YES | 9971 |
AF | Scheduled but not Collected. | Null Data Qualifier | NULL | YES | 9972 |
AG | Sample Time out of Limits. | Null Data Qualifier | NULL | YES | 9973 |
AH | Sample Flow Rate or CV out of Limits. | Null Data Qualifier | NULL | YES | 9974 |
AI | Insufficient Data (cannot calculate). | Null Data Qualifier | NULL | YES | 9975 |
AJ | Filter Damage. | Null Data Qualifier | NULL | YES | 9976 |
AK | Filter Leak. | Null Data Qualifier | NULL | YES | 9977 |
AL | Voided by Operator. | Null Data Qualifier | NULL | YES | 9978 |
AM | Miscellaneous Void. | Null Data Qualifier | NULL | YES | 9979 |
AN | Machine Malfunction. | Null Data Qualifier | NULL | YES | 9980 |
AO | Bad Weather. | Null Data Qualifier | NULL | YES | 9981 |
AP | Vandalism. | Null Data Qualifier | NULL | YES | 9982 |
AQ | Collection Error. | Null Data Qualifier | NULL | YES | 9983 |
AR | Lab Error. | Null Data Qualifier | NULL | YES | 9984 |
AS | Poor Quality Assurance Results. | Null Data Qualifier | NULL | YES | 9985 |
AT | Calibration. | Null Data Qualifier | NULL | YES | 9986 |
AU | Monitoring Waived. | Null Data Qualifier | NULL | YES | 9987 |
AV | Power Failure. | Null Data Qualifier | NULL | YES | 9988 |
AW | Wildlife Damage. | Null Data Qualifier | NULL | YES | 9989 |
AX | Precision Check. | Null Data Qualifier | NULL | YES | 9990 |
AY | Q C Control Points (zero/span). | Null Data Qualifier | NULL | YES | 9991 |
AZ | Q C Audit. | Null Data Qualifier | NULL | YES | 9992 |
BA | Maintenance/Routine Repairs. | Null Data Qualifier | NULL | YES | 9993 |
BB | Unable to Reach Site. | Null Data Qualifier | NULL | YES | 9994 |
BC | Multi-point Calibration. | Null Data Qualifier | NULL | YES | 9995 |
BD | Auto Calibration. | Null Data Qualifier | NULL | YES | 9996 |
BE | Building/Site Repair. | Null Data Qualifier | NULL | YES | 9997 |
BF | Precision/Zero/Span. | Null Data Qualifier | NULL | YES | 9998 |
BG | Missing ozone data not likely to exceed level of standard. | Null Data Qualifier | NULL | YES | 9966 |
BH | Interference/co-elution/misidentification. | Null Data Qualifier | NULL | YES | 9965 |
BI | Lost or damaged in transit. | Null Data Qualifier | NULL | YES | 9964 |
BJ | Operator Error. | Null Data Qualifier | NULL | YES | 9963 |
BK | Site computer/data logger down. | Null Data Qualifier | NULL | YES | 9962 |
BL | QA Audit. | Null Data Qualifier | NULL | YES | 9961 |
BM | Accuracy check. | Null Data Qualifier | NULL | YES | 9960 |
BN | Sample Value Exceeds Media Limit. | Null Data Qualifier | NULL | YES | 9947 |
BR | Sample Value Below Acceptable Range. | Null Data Qualifier | NULL | YES | |
CS | Laboratory Calibration Standard. | Null Data Qualifier | NULL | YES | 9953 |
DA | Aberrant Data (Corrupt Files, Aberrant Chromatography, Spikes, Shifts). | Null Data Qualifier | NULL | YES | 9951 |
DL | Detection Limit Analyses. | Null Data Qualifier | NULL | YES | 9949 |
EC | Exceeds Critical Criteria. | Null Data Qualifier | NULL | YES | |
FI | Filter Inspection Flag. | Null Data Qualifier | NULL | YES | 9959 |
MB | Method Blank (Analytical). | Null Data Qualifier | NULL | YES | 9955 |
MC | Module End Cap Missing. | Null Data Qualifier | NULL | YES | 9958 |
QV | Quality Control Multi-point Verification. | Null Data Qualifier | NULL | YES | |
SA | Storm Approaching. | Null Data Qualifier | NULL | YES | 9957 |
SC | Sampler Contamination. | Null Data Qualifier | NULL | YES | 9948 |
ST | Calibration Verification Standard. | Null Data Qualifier | NULL | YES | 9954 |
SV | Sample Volume out of limits. | Null Data Qualifier | NULL | YES | |
TC | Component Check & Retention Time Standard. | Null Data Qualifier | NULL | YES | 9952 |
TS | Holding Time Or Transport Temperature Is Out Of Specs. | Null Data Qualifier | NULL | YES | 9956 |
XX | Experimental Data. | Null Data Qualifier | NULL | YES | 9950 |
1C | A 1-Point QC check exceeds acceptance criteria but there is compelling evidence that the analyzer data is valid. | Missing QA/QC Audit | NULL QC | YES | |
1F | No 1 Point QC but need to count for completeness | Missing QA/QC Audit | NULL QC | YES | |
IA | African Dust. | Informational Only | INFORM | YES | |
IB | Asian Dust. | Informational Only | INFORM | YES | |
IC | Chem. Spills & Indust Accidents. | Informational Only | INFORM | YES | |
ID | Cleanup After a Major Disaster. | Informational Only | INFORM | YES | |
IE | Demolition. | Informational Only | INFORM | YES | |
IF | Fire - Canadian. | Informational Only | INFORM | YES | |
IG | Fire - Mexico/Central America. | Informational Only | INFORM | YES | |
IH | Fireworks. | Informational Only | INFORM | YES | |
II | High Pollen Count. | Informational Only | INFORM | YES | |
IJ | High Winds. | Informational Only | INFORM | YES | |
IK | Infrequent Large Gatherings. | Informational Only | INFORM | YES | |
IL | Other. | Informational Only | INFORM | YES | |
IM | Prescribed Fire. | Informational Only | INFORM | YES | |
IN | Seismic Activity. | Informational Only | INFORM | YES | |
IO | Stratospheric Ozone Intrusion. | Informational Only | INFORM | YES | |
IP | Structural Fire. | Informational Only | INFORM | YES | |
IQ | Terrorist Act. | Informational Only | INFORM | YES | |
IR | Unique Traffic Disruption. | Informational Only | INFORM | YES | |
IS | Volcanic Eruptions. | Informational Only | INFORM | YES | |
IT | Wildfire-U. S. | Informational Only | INFORM | YES | |
J | Construction. | Informational Only | INFORM | YES | |
E | Forest Fire. | Request Exclusion | REQEXC | NO | |
RU | Wildland Fire Use Fire-U. S. | Request Exclusion | REQEXC | NO | |
8 | QA/QC Unknown. | Quality Assurance Qualifier | QA | NO | |
PQ | Values Between PQL And MDL. | Quality Assurance Qualifier | QA | NO | |
T | Multiple PM2.5 Validity Flags. | Quality Assurance Qualifier | QA | NO | |
A | High Winds. | Informational Only | INFORM | NO | |
B | Stratospheric Ozone Intrusion. | Informational Only | INFORM | NO | |
C | Volcanic Eruption. | Informational Only | INFORM | NO | |
D | Sandblasting. | Informational Only | INFORM | NO | |
F | Structural Fire. | Informational Only | INFORM | NO | |
G | High Pollen Count. | Informational Only | INFORM | NO | |
H | Chem. Spills & Indust. Accidents. | Informational Only | INFORM | NO | |
I | Unusual Traffic Congestion. | Informational Only | INFORM | NO | |
IU | Wildland Fire Use Fire-U. S. | Informational Only | INFORM | NO | |
K | Agricultural Tilling. | Informational Only | INFORM | NO | |
L | Highway Construction. | Informational Only | INFORM | NO | |
M | Rerouting of Traffic. | Informational Only | INFORM | NO | |
N | Sanding/Salting of Streets. | Informational Only | INFORM | NO | |
O | Infrequent Large Gatherings. | Informational Only | INFORM | NO | |
P | Roofing Operations. | Informational Only | INFORM | NO | |
Q | Prescribed Burning. | Informational Only | INFORM | NO | |
R | Cleanup After a Major Disaster. | Informational Only | INFORM | NO | |
S | Seismic Activity. | Informational Only | INFORM | NO | |
U | Sahara Dust. | Informational Only | INFORM | NO | |
Z | Other event. | Informational Only | INFORM | NO |