Eight Points to Keep in Mind When Considering a Lighting Upgrade
August 4, 2017 - Lighting
By Joe Engle and Summer Albergotti
We’ve toured our fair share of facilities in search of potential opportunities or issues that can be solved by better lighting. The variety of applications is amazing, but in today's market there's one consistent similarity – the opportunity associated with better lighting.
When touring a facility, we take note of specifics so we are able to supply the area with the lighting it needs. Elements we take into account include the measurements and color of the ceiling, walls and floor, the ceiling structure, obstructions hindering the lighting in the space, fixture mounting height and the expected ambient temperature range where the light fixtures are/will be located.
Even with the wide variety in facilities, there are a few guidelines that will help facility managers and contractors when considering a lighting upgrade. Those guidelines include:
- Understand the visual tasks performed in the space. This may be the most important consideration. After all, the reason for lighting is to ensure workers can see to perform their jobs properly. Do they need light on a horizontal plane or a vertical plane? How often will employees be looking up toward the lights? Is color rendering an important part of the job? Some of the largest factors that determine the amount of light you need are: the time needed to focus on an object in the space, the size of an object you are working with, the reflectances in the space, and the contrast between an object and its background.
- Scrutinize the environment. Is it clean or dirty? Hot or cold? Dry or humid? Will the light fixtures be subjected to a wash down procedure? Are corrosive chemicals in the area? In what concentrations? Is it a hazardous location rated area? If so, what is the rating? Take dust or fiber collection issues, for example. On many occasions the light output can be hindered, particularly in textile areas, by dust and/or fibers hanging from fixtures. Also, consider if chemicals will be used to clean the washdown fixtures. We’ve seen in many applications where more than just water is used and that can cause corrosion of fixtures if they are not properly rated for those chemicals.
- Precisely assess how much light is need. Good light levels are always a balance between safety, energy usage and the vision of those working in the area. The amount of light is an important part of doing the job well and safely, but too much light will waste energy and money. The Illuminating Engineering Society of North America, IESNA, produces a Recommended Practice, RP-7, which helps determine the correct light levels for most industrial situations. Consider if overhead lighting alone is sufficient or if individual task lighting might be appropriate or necessary for machinery or assembly areas. For more intricate or small assemblies, or even in areas where products are inspected for flaws and defects, individual task lighting could be helpful to achieve the level of visibility for those tasks.
- Determine the need for uplight? Some light fixtures are designed to put light on the ceiling to eliminate the cave effect, which is when the visual ceiling is at the level of the fixtures and not the structure ceiling level. Some restaurants and retail spaces paint their ceilings black to achieve this effect, which makes their areas appear smaller and offers a more intimate setting. In most industrial facilities it is better to open up the space and light the ceiling, which reduces shadowing and contrast and helps visual acuity. Whether or not this feature will benefit the area depends on the color of the ceiling. If it is dirty and dark, any light directed up will be wasted. On a white or light colored ceiling, however, the uplight will reflect back and open up the space.
- Identify any voltage or circuiting issues. When relighting a facility, the capacity and condition of the existing wiring must be examined. It is important to have the correct voltage and current carrying capacity to support the new fixtures. The existing wiring also needs to be in good condition. Don’t install new fixtures that will last a long time on a building circuit that has limited life. Investigate any and all surge issues – be it incoming or outgoing.
- Request the facility electrical plan. Regardless of how old it is, this can be a helpful tool in auditing the space. If electrical plans are not available, obtain a copy of the evacuation route in a building. It can help keep you on track identifying the areas you’ve already audited and what you have left. We’re all human and it is easy to get turned around in many facilities.
- Apply measurement tricks. Most construction concrete blocks are 8" tall. Measure one at eye level and count to see how high a wall is. Ceiling tile are normally 2' x 4' or 2' x 2'. Use this to estimate fixture spacing. Estimate reflectance of a wall or floor by using a basic light meter. Aim the light meter at the wall about 1' away from the wall. Take a reading. Turn the same meter away from the wall at 1' away. The first reading divided by the second is the approximate percentage of reflectance on that wall.
- Don’t Forget the Controls! Establish a lighting controls baseline. Are there currently any controls in place? Are they working? Do they meet the needs of the facility? Do they meet current energy codes? Once these questions are answered, we can look for opportunities to use controls to save energy, meet the codes and provide value. See if you can identify “Low Hanging Fruit” (pun intended). For example, the simple addition of an occupancy sensor to a high bay fixture in a warehouse can have a huge impact on energy use and maintenance. Lighting fixtures that are off or dimmed not only consume less energy, they reduce the hours a fixture is on thereby increasing the time interval between re-lamping or additional required service. And don’t overlook the potential for controls to tune your lighting system. Controls allow for the user to lower the output/energy used by the fixture when full output is either not desired or required. A few simple strategic tips:
- Look for opportunities to automatically turn off lighting when not needed (occupancy sensor and time based scheduling)
- Look for opportunities to use natural light to either reduce the need for artificial lighting or completely eliminate it during daylight hours.
- Tune your lighting system. Make adjustments to ensure you are only using the light you need, and reduce output and energy consumption wherever possible.
As a final comment, we’d suggest creating a toolkit for facility audits. If you put a light meter, digital infrared thermometer, tape measure, clipboard with grid paper and a copy of the RP-7 Recommended Practice on Industrial Lighting in a tool bag, you will be ready for your next facility audit. And take advantage of audit worksheets that can help you make sure you are taking down all of the right metrics while you are at a facility.
Joe Engle is the product manager new product innovation at Hubbell Lighting, one of the largest lighting fixture manufacturers in North America. He can be reached at email@example.com.
Summer Albergotti is a technical training specialist with Hubbell’s Lighting Solutions Center. She can be reached at firstname.lastname@example.org.
Hubbell’s audit worksheet is available at http://www.hubbelllighting.com/solutions/retrofit/tools/audit-design/.