Each Science Header Line file, Science Data file, Science Trailer file and Image file has a corresponding Data Quality file that contains flags for bad or suspect data. If a data value is 'good', its corresponding data quality value is zero. If because of data-dropouts the data has been filled, the data quality value is sixteen. If the the data failed the Reed-Solomon error check, the data quality value is one. These Data Quality files are identified by the extensions ``.Q0H'', ``.Q0D'', ``.XQH'', ``.XQD'', ``.Q1H'', and ``.Q1D''.
