The VIIRS/JPSS2 Active Fires 6-Min L2 Swath 375m NRT with short-name VNP14IMG_NRT is a Near Real Time (NRT) active fire detection data product (Schroeder 2014). The product is built on the EOS/MODIS fire product heritage [Kaufman et al., 1998; Giglio et al., 2003], using a multi-spectral contextual algorithm to identify sub-pixel fire activity and other thermal anomalies in the Level 1 (swath) input data. The algorithm uses all five 375 m VIIRS channels to detect fires and separate land, water, and cloud pixels in the image. Additional 750 m channels complement the available VIIRS multispectral data. Those channels are used as input to the baseline active fire detection product, which provides continuity to the EOS/MODIS 1 km Fire and Thermal Anomalies product.<br />
The VIIRS 375 m fire detection data is a 6-min Level 2 swath product based on the input Science Data Record (SDR) Level 1 swath format. The NRT product is currently available through NASA's Land, Atmosphere Near real-time Capability for EOS (LANCE). The data are formatted as NetCDF4 files.

For more information read:
Schroeder, W., Oliva, P., Giglio, L., & Csiszar, I. A. (2014). The New VIIRS 375m active fire detection data product: algorithm description and initial assessment. Remote Sensing of Environment, 143, 85-96. doi:10.1016/j.rse.2013.12.008 PDF from UMD