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Ten factors for flood, street lighting, luminaires

Short answer

a) Flood design: surface size/reflectance, surrounding brightness, required lux, projector distance, beam spread, CU, DF, WLF, lamp type/wattage, glare. b) Street: road class, required E_av/uniformity, width, mounting height, spacing, arrangement, surface reflection, glare control, junctions, maintenance. c) Luminaires: light distribution, lamp type/efficacy, light output ratio, glare control, colour rendering, IP rating, mechanical strength, mounting, maintenance ease, cost.

State 10 factors to be considered while: a) Designing of flood lighting system b) Designing of street lighting system c) Selection of luminaries

a) Factors in designing a floodlighting system

  1. Size and shape of the surface to be lit (area A).
  2. Colour and reflection factor of the surface.
  3. Brightness of the surroundings.
  4. Required illumination level (lux).
  5. Distance and location of projectors.
  6. Beam spread of projectors (narrow, medium, wide).
  7. Coefficient of utilisation / beam factor.
  8. Depreciation (maintenance) factor.
  9. Waste light factor (spill light).
  10. Lamp type, wattage, efficacy and colour; glare to viewers and traffic; cost.

b) Factors in designing a street lighting system

  1. Class of road and density of traffic (vehicles and pedestrians).
  2. Required average illumination/luminance.
  3. Uniformity ratio (E_min/E_av).
  4. Road width and number of lanes.
  5. Mounting height of lamps.
  6. Spacing between poles (S/h ratio).
  7. Arrangement: single-side, staggered, opposite, central.
  8. Road surface reflection (rough/smooth, dry/wet).
  9. Glare control and luminaire distribution (cut-off type).
  10. Junctions, curves, bridges; maintenance factor; energy cost and control (photocell, timer, dimming).

c) Factors in selecting luminaires

  1. Light distribution (direct, indirect, cut-off, beam spread).
  2. Lamp type and efficacy (LED, HPSV, metal halide).
  3. Light output ratio / efficiency of the fitting.
  4. Glare control (shielding angle, diffusers, louvres).
  5. Colour rendering and colour temperature.
  6. Environment: IP rating against dust and water; flame-proof or corrosion-proof where needed.
  7. Mechanical strength and heat dissipation.
  8. Mounting method and aiming facility.
  9. Ease of maintenance and cleaning.
  10. Initial cost, life and running cost; appearance.

✓ Answer checked by Claude Opus 5.5 (high effort)

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