VISIBILITY UNDER NIGHT DRIVING CONDITIONS. PART 2. FIELD MEASUREMENTS USING DISC OBSTACLES AND A PEDESTRIAN DUMMY

The visibilities of a pedestrian dummy and disc objects of varying size and contrast were measured under dynamic night driving conditions on an unlit open road and in a road lighting situation for which the average pavement luminance was 0.8 cd/m2. The visibilities of the objects could largely be described by a standard luminous increment-visual area characteristic. Under road lighting conditions, negative contrasts (silhouette vision) were found to give slightly greater visibilities than positive contrasts. It was found that a contrast multiplier of 4 was required in applying laboratory 50% probability of detection thresholds to a 'just visible' criterion level of visibility in the field experiments, though in practical conditions contrast multipliers as large as 30 may be required. (a) for abstract of part I see IRRD no. 215842. /TRRL/

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  • Corporate Authors:

    Illuminating Engineering Society

    York House, 199 Westminster Bridge Road
    London SE1 7UN,   England 
  • Authors:
    • HILLS, B L
  • Publication Date: 1975

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Filing Info

  • Accession Number: 00134259
  • Record Type: Publication
  • Source Agency: Transport and Road Research Laboratory (TRRL)
  • Files: ITRD, TRIS
  • Created Date: Jul 22 1977 12:00AM