FBL has various meanings in the Military category. Discover the full forms, definitions, and usage contexts of FBL in Military.
A unit of measure for lumber equal to 1 inch thick by 12 inches wide by 12 inches long. Examples: 1" x 12" x 16' = 16 board feet, 2" x 12" x 16' = 32 board feet. Space in a window sash for a single pane of glass. Also, a pane of glass. A factor used in calculating luminance after a given period of time and under given conditions. It takes into account temperature and voltage variations, dirt accumulation on luminaire and lit surfaces, lamp depreciation, maintenance procedures and atmos.
MilitaryLast updated: