Whether a large academic or corporate campus or residential neighborhood, the need for thorough yet efficient exterior lighting can seem like a daunting task. Not only can an electrical engineer design improvements to your existing exterior lighting, but we can also help you from the beginning of the planning phase. Through an exterior lighting study, we equip you with all the information necessary to decide where to begin and how to address your campus’ lighting needs.
We start by establishing a baseline criteria based on the Illuminating Engineering Society’s (IES) lighting level standards of measurement in foot-candles (FC). Each area surveyed falls into one of three categories of measurable illumination:
- Deficient: Areas that have illumination less than the minimum level of security (less than 0.2FC)
- Minimum: Areas that have illumination between the minimum and enhanced levels of security (0.2FC – 0.5FC)
- Preferred: Areas that have illumination above the enhanced levels of security (more than 0.5FC)
To measure the lighting levels, we utilize a custom cart equipped with a light sensor and GPS data logger. The cart has a modified steel arm to hold the sensor away from other objects or people to avoid shadows and ensure accurate data. With this cart, a two-person team walks the area over the course of several nights (depending on the size of the campus or neighborhood) to collect data and take photos. Light readings are conducted at intervals of approximately 15 feet, while the equipment logs data every one second to provide more sample data for evaluation. Each point of raw data contains latitude and longitude, elevation, the illumination reading (in kLux), and the exact time. From there, the data is converted as necessary and sorted into the three aforementioned categories.
Once we complete our data collection and analysis, our deliverables to the client consist of a report, photos, and recommendations. PDF files show maps of each area measured with colored hatching and measured foot-candle readings (as shown below). Our recommendations, presented in a spreadsheet format, call out the areas where lighting should be repaired, replaced, upgraded, or added, or where vegetation needs to be trimmed. These recommendations are based upon field observations, in addition to the data collected, and differing uses for each area are taken into account (i.e. a parking lot versus remote areas).
At the completion of such a study, the client is equipped with the information necessary to prioritize and set aside funding for campus lighting improvements, as well as an action plan to address any stakeholder concerns. From there, should the client decide to move forward with improvements, BHB is available and happy to provide further electrical engineering services.
With the use of the GPS data logger tool, frequency of data can be expanded and taken more frequently, opening up the opportunity to survey different types of projects. It could translate well to large sections of roadway, walking trails, or special districts. A map like this combined with recommendations is great for organizations needing to prioritize funding or set up future projects.
For more information about conducting an exterior lighting study, contact Thomas Wilson at twilson@bhbinc.com.
