| 1 | sky fiber (SKY) |
| 2 | too little wavelength coverage (WCOVERAGE<0.18) (LITTLE_COVERAGE) |
| 4 | chi-squared of best fit is too close to that of second best (reduced chi-squared <0.01) (SMALL_DELTA_CHI2) |
| 8 | synthetic spectrum is negative (only set for stars and QSOs) (NEGATIVE_MODEL) |
| 16 | fraction of points more than 5 sigma away from best model is too large (>0.05) (MANY_OUTLIERS) |
| 32 | chi-squared minimum at edge of the redshift fitting range (Z_ERR set to -1) (Z_FITLIMIT) |
| 64 | a QSO line exhibits negative emission, triggered only in QSO spectra, if C_IV, C_III, Mg_II, H_beta, or H_alpha has LINEAREA+3*LINEAREA_ERR<0 (NEGATIVE_EMISSION) |
| 128 | the fiber was unplugged or damaged, and the location of any spectrum is unknown (UNPLUGGED) |
| 256 | catastrophically bad targeting data (e.g. bad astrometry) (BAD_TARGET) |
| 512 | No data for this fiber, e.g. because spectrograph was broken during this exposure (ivar=0 for all pixels) (NODATA) |