PRELIMINARY DETERMINATION OF LUMINANCE IN STREET LIGHTING: PRESENTATION OF DATA AND CONTROL OF RESULTS

THE AUTHORS RECALL THE SPEECH, MADE BY THE MINISTER OF THE INTERIOR AT THE OCCASION OF THE PUBLICATION OF THE MANUAL OF COMMON SPECIFICATIONS, IN MARCH 1974, IN WHICH THE MAIN QUALITY CRITERIA FOR PUBLIC LIGHTING ARE SAID TO BE THE LEVEL AND UNIFORMITY OF LUMINANCE. LUMINANCE DEPENDS ON THE OPTICAL QUALITIES OF THE ROAD SURFACING FOR WHICH THE CONTRACTOR CANNOT BE HELD RESPONSIBLE. THESE QUALITIES CAN VARY DEPENDING ON THE CONSTRUCTION SITE OR ATMOSPHERIC CONDITIONS. THE AIM OF THE ARTICLE IS TWO-FOLD: (1) TO OUTLINE A METHOD TO FOLLOW FOR THE CALCULATION OF LUMINANCE; (2) TO REDEFINE A NEW METHOD OF PRESENTING LIGHTING VALUES WITHIN THE ACCEPTANCE TEST.