Light at Night and Safety

Chicago Alley LightingChicago Alley Lighting Project E.N. Morrow, S.A. Hutton, Illinois Criminal Justice Information Authority, April, 2000


In October of 1998, the Mayor’s Office in the City of Chicago and the Department of Streets and Sanitation began a multi-stage plan to reduce crime through improved street and alley lighting. The first part of the plan sought to upgrade and improve the city’s 175,000 streetlights, which illuminate the arterial and residential streets. The second part of the plan involves repairing and upgrading the lighting in and around viaducts and Chicago Transit Authority stations. The final part of the plan has been to boost lighting levels in alleys across the city as a tool for public safety and fighting crime. … While both the experimental and control areas experienced similar increases in all offense categories between pre-and post-installation in the experimental area, the overall increases in the experimental area appear to be more pronounced (40 percent increase versus 19 percent increase in the control area). … Based on the analysis, it is difficult to point to any conclusive evidence that increased alley lighting had an effect on crime.

Age and Glare Recovery TimeAge and Glare Recovery Time for Low-Contrast Stimuli F. Schieber, December,1997


The purpose of this study was to obtain a rigorous experimental estimate of the time required to recover from the deleterious effects of glare. Low contrast test stimuli were employed to increase the potential sensitivity of the procedure. Multiple age groups were sampled since susceptibility to glare effects is known to increase with advancing years. Glare recovery time assessments were collected from 12 young, 12 middle-aged and 16 older adults. Subjects were presented with 10 sec exposures to an intense glare source under highly controlled experimental conditions. Upon the offset of the glare exposure period, the time required to regain sensitivity for low contrast test stimuli was measured. Relative to their younger counterparts, older subjects required 3-times longer to recover from glare exposure. These findings suggest that the dynamic components of glare effects …

To celebrate, promote, and protect the glorious dark skies of Flagstaff and northern Arizona.