Semi-cutoff (Lighting)
Semi-cutoff (Lighting) : Luminaire light distribution is classified as semi-cutoff when the candlepower per 1000 lamp lumens does not numerically exceed 50 (5.0%) at an angle of 90 degrees above nadir (horizontal), and 200 (20%) at a vertical angle of 80 degrees above nadir. This applies to any lateral angle around the luminaire