Modern Lighting Audits. Technology supporting designers and contractors to verify lighting conditions

摘要

LED-based lighting products are rapidly evolving and being adapted to virtually every application. Similarly, standards and systems to define and measure their performance are evolving as well. This applies to all phases of LEO development and use, from basic R&D, to design, implementation, post-install verification, audits, and maintenance. Today, purchases of LED lamps and luminaires for new construction or retrofits are largely driven by energy efficiency (efficacy), purchasing and installation cost, and building or regulatory code compliance. More specific light quality performance metrics, such as illuminance uniformity, flicker, CRI, or metameric indices, are of lower priority or absent from the criteria list. Typical post-installation light audits only verify basic illuminance levels, often with uncalibrated or inaccurate instruments. While the CIE S 025 international standard recommends methods for measuring LED luminaires, and most lighting manufacturers have adopted these practices, these are not widely used during lighting audits. Further, rapidly changing LED luminaire products require different measurement technologies and processes to accurately determine design/build compliance. This is particularly prudent given today's wide range of luminaire technologies, controllers, drivers, and product build qualities. Available lighting design software tools support architects, engineers, and designers with the calculation and simulation of luminance levels and even correlated color temperature (CCT), but little is available for on-site verification tools. Nevertheless, verification can insure conformance for specific application requirements such as detailed task-work, food inspection, color critical viewing, warehouse isles, safety exit signs, roadway lighting, etc. This paper describes a novel solution combining existing CAD lighting design software, on-site measurements using spectro-radiometers and imaging illuminance meters, and new lighting auditing software to report and verify detailed performance metrics of the actual end-use environment. This is particularly useful for assessing the unique spectral and light quality characteristics of LED-based lighting.