Atmosphere Profile (07_L2) and Cloud Mask (35_L2) HDF products are produced from the Program Executable (PGE) identified as PGE03. One may identify the maturity and quality of an HDF data product by finding the PGE (program executable) version that was used to produce the file. This information can be obtained directly from the HDF file itself by using the HDF utility ncdump. The (UNIX) command is ncdump -h *.hdf | awk '/PGEVERSIONCLASS/,/END_GROUP/' . One may also find PGE version information in the ascii text met (metadata) file associated with a particular HDF file. Another slightly less reliable way to determine the PGE version is through the "processing date & time" field of the HDF filename (field #5 in L2 HDF files, see HDF Filename convention). Users then match the processing date in the HDF filename with the production start date for various PGE versions in blue in the listing below. If you have any questions about this, contact Paul Hubanks.