You work as the plant and facilities electrical engineer at a three-shift factory with an adjacent administration building. This administration building is home to the division vice president and her entire reporting structure for the division. Thus, it hosts various division departments, including product engineering, inside sales, marketing, finance, purchasing, and personnel. In short, it hosts everybody in the division except outside sales, plant maintenance, and production. Many of these people have made their career in the company, so there’s a lot of knowledge residing in that building. Thus, the division vice president takes employee complaints seriously.
One complaint she has heard more often lately is the lighting isn’t sufficient. She wrote a work request to have the lighting analyzed and sent that to the maintenance department. The work analyst consequently wrote a work order to have light readings taken at each workstation, the coffee kiosk, the hallways, and the bathrooms. All of these came back normal, and a reply was sent to the division vice president with this information. She was not please, because this didn’t solve anything, and she still has unhappy employees.
She called you to her office, explained this chain of events, and asked you to get back to her within 24 hours with an actual plan to fix the problem. “If people say there’s not enough light, then I don’t care what your light meters say. There’s not enough light,” she tells you.
What should be your approach to solving this?
Answer to Quiz. It’s good that maintenance checked the lighting at each workstation and even at the coffee kiosk. However, they didn’t check the worker at each workstation, and that’s where the complaints are coming from. Older workers simply need more light. What’s “normal” in some lighting reference may have been sufficient for these people when they were younger, but it’s not enough for them now — and now is what matters.
The Illuminating Engineering Society (IES) recommends 300 lm/m2 and the U.S. General Services Administration (GSA) recommends 500 lm/m2. You could scratch your head, wonder why the GSA number is 150% greater, and try to come up with the “correct” number. But your boss has given you a directive, and that is to make the light satisfactory for those who are complaining about insufficient light. She already indicated displeasure with merely matching numbers.
Go back to the lighting survey and look at how many lumens you have. Let’s say it’s 400 lm/m2. And let’s say upgrading the troffer lighting by replacing the 40W fluorescent systems with newer LEDs designed specifically for offices will bring you in slightly higher than 500 lm/m2 in this particular office space. But if half the people in a given area really need 600 lm/m2, you’ve just spent a lot of money and fallen short of fixing the problem.
Even if you did fix it by this means, the lighting could be insufficient in five years due to a combination of dirty lenses and another five years of employee aging. And perhaps younger people won’t like the glare of excess ambient light.
But there is an elegant solution you can bring to your division vice president tomorrow. It is twofold.
First, assess the existing lighting to see who actually wants more light and how much they think they need. Do this by asking individuals to rate the sufficiency of their light on a scale of 1 to 5, and record the answer by individual and workstation location.
If the existing lighting gets poor marks generally, you need to upgrade the lighting (for starters). Plan to upgrade the luminaires to LED versions designed specifically for this type of space.
If most people have no complaints, the issue is user-specific. This means you probably should not change the general lighting. It may be a good idea, however, to write a work order to have troffer lenses cleaned or replaced as needed. Also check the relamping schedule. If the office is just about due, the “approaching end of life” loss in lamp luminance could be the reason for at least some of the complaints.
You don’t want to wait to see if the relamping fixes the problem because the problem will return late in the next cycle if it does. And if it doesn’t fix the problem, you’ve just wasted a big relamping cost when you should have upgraded the lighting.
The next step is to increase the lighting at specific work stations, which are those belonging to the workers who say they need more light. Visit a few cubicles and observe how people are seated in relation to places where you might mount strip lighting for increased ambient lighting. LED strip lighting is easy to install, and the flexibility it gives you design-wise is excellent. It’s also inexpensive. One thing you’ll need to be alert to is where to mount the driver; it will likely need to be in free air so it stays cool.
Look at where you can mount strips to provide “over the shoulder” lighting, downlighting, and sidelighting. Work with an individual to assess how the lighting would affect his or her environment. You want to avoid generating shadows and you want to increase the perception of good ambient lighting by lighting up this person’s specific work area.
To get this right, affix LED strips in a temporary fashion. You can use painter’s tape to temporarily mount them, and having a small wiring mess for a few days shouldn’t be a big deal. Once you have a decent design, draw it up and then move your test rig to another cubicle and repeat the experiment. You may get a little more insight from this second person. Finalize the design and add the LED strip lighting to all of the cubicles where the occupant says the lighting is not sufficient. This will increase the perceived ambient lighting in that cubicle. Be sure to add a switch to the driver, so this can be turned off or on as needed.
To prevent complaints on down the road, provide task lighting to every cubicle. A good option is something that can be repositioned by the user. Plenty of options are available, including designs that use swivels, clamps, mini-tracks, and telescoping arms. Plug-in designs will also eliminate the cost of hardwiring.
What about battery-powered lights that charge via USB port? These may be convenient for the installer, but they are inconvenient for the user. Consider them only when no other option is practicable.
