This file contains the QC flags used in the various source datasets
and their meanings.
====================================


ocean.fdb
0  not checked
1  bad
2  suspicious
3  calculated
4  acceptable
5  passed primary QC (set of algorithms: ... including sigma tests?)
6  passed expert control (visual or other non-standard methods)
7  passed secondary QC (crossover, inversion analyzes) and quality confirmed (otherwise QF has to be changed to 1,2 or 4)
8  passed secondary QC (crossover, inversion analyzes) and adjusted
9

GLODAP Product
Primary (PQF1)
0 Interpolated or calculated value
2 Acceptable/Average of replicate/Manual chromatographic peak measurement
9 No data/Data not received/Value not reported

Secondary (SQF)
0 data have not been subjected to full secondary QC
1 data have been subjected to full secondary QC



NODC WOD (observed levels)
0  Accepted value
1  Range outlier
2  Failed inversion check
3  Failed gradient check
4  Observed level "bullseye" flag and zero gradient check
5  Combined gradient and inversion checks
6  Failed range and inversion checks
7  Failed range and gradient checks
8  Failed range and questionable data checks
9  Failed range and combined gradient and inversion checks


Seadatanet QC flags
0  no quality control
1  good value
2  probably good value
3  probably bad value
4  bad value
5  changed value
6  value below detection
7  value in excess
8  interpolated value
9  missing value
A  value phenomenon uncertain


WOCE (water sample)
1 Sample for this measurement was drawn from water bottle but analysis not
  received. Note that if water is drawn for any measurement from a water bottle, the
  quality code for that parameter should be set equal to 1 initially to help ensure that
  all water samples are accounted for.
2 Acceptable measurement.
3 Questionable measurement.
4 Bad measurement.
5 Not reported.
6 Mean of replicate measurements (Number of replicates should be specified in the .DOC file and the replicate data tabulated there).
7 Manual chromatographic peak measurement.
8 Irregular digital chromatographic peak integration.
9 Sample not drawn for this measurement from this bottle.


WOCE (CTD data)
1 Not calibrated.
2 Acceptable measurement.
3 Questionable measurement.
4 Bad measurement.
5 Not reported.
6 Interpolated over a pressure interval larger than 2 dbar.
7 Despiked.
8 Not used for CTD data.
9 Not sampled.


The WMO IGOSS observation quality codes are:
0 No quality control yet assigned to this element
1 The element appears to be correct
2 The element is probably good
3 The element is probably bad
4 The element appears erroneous
5 The element has been changed
6 to 8 Reserved for future use
9 The element is missing



ODV generic quality flags
0  Good
1  Unknown
4  Questionable
8  Bad


OceanSITES quality flags – proposed, not yet definitive
0  No QC was performed
1  Good data
2  Probably good data
3  Bad data that are potentially correctable
4  Bad data
5  Value changed
7  Nominal value
8  Interpolated value
9  Missing value


ARGO Real-time comment/Delayed-mode comment
3.2.1 Reference table 2: measurement flag scale (Argo User’s manual)
0	No QC was performed	
1	Good data
2	Probably good data
3	Bad data that are potentially correctable
4 	Bad data
5	Value changed
6	Not used
7	Not used
8 	Estimated (interpolated, extrapolated or other estimation)
9	Missing value



GODAR
Table 8. Meaning of the quality control Flag_ of parameter tables (Korablev et al., 2018)
#	Flag	Description
1	0	Flag is not set
2	1	Accuracy lost (from source) 
3	2	Suspicious value (from source) 
4	4	Erroneous value (from source)
5	8	Interpolated value
6	16	Chemistry units recalculated
7	32	Depth from pressure 
8	64	Range error
9	128	Stability error
10	256	=Reserved=
11	512	Duplicate analysis 
12	1024	Outside 3 SD (Standard Deviation)
13	2048	Outside 4 SD 
14	4096	Outside 5 SD
15	8192	= Reserved= 
16	16384	Suspicious value
17	32768	Erroneous value