Urban Reflective Sources of Glare

2012 - 2014

J. Alstan Jakubiec and Christoph F. Reinhart
Project work done while at the MIT Sustainable Design Lab.

 

Disability glare, visual impairment due to extreme brightness or contrast, can be caused by intense reflections from new constructions nearby existing transportation or building infrastructure. A case study analysis is performed of a disability glare hazard at an airport created by the installation of a large array of photovoltaic panels between an air traffic control tower and the aircraft taxiway. The panels reflect blinding quantities of daylight into the control tower, produce temporary after images and dangerously obscure taxiing aircraft. The existing FAA guidelines for installation of solar technologies are discussed relative to their shortcomings in identifying the glare hazard.

High dynamic range photography is used to analyze the glaring situation at the airport, and the authors propose a maximum brightness threshold of 30,000 cd/m2 based on the physiology of human vision and the brightness of tasks necessary for air traffic controllers at the case-study airport. Detailed reflectivity and three-dimensional models of the photovoltaic panels and the airport are created and validated against measured data. Using these models, an annual analysis is performed of the glare hazard. This analysis is displayed temporally using graphs and spatially using images that indicate where the glaring reflections originate. Such information is useful in identifying potential for disability glare before new constructions are built. Finally, the authors use the new method to analyze designs for remediation of the glare hazard.

 

Publications
Jakubiec, J. A., & Reinhart, C. F. (2014). Assessing disability glare potential of reflections from new construction. Transportation Research Record: Journal of the Transportation Research Board, 2449(1), 114-122.

Jakubiec, J. A., & Reinhart, C. F. (2014). Assessing disability glare potential due to reflections from new constructions: A case study analysis and recommendations for the future. In Proceedings of the Transportation Research Board 93rd Annual Meeting.