Home Officed
Find home office furniture, equipment and services

    Office Lighting

    office lighting
    What’s the Best Lighting for an Office?

    Our company recently changed our fluorescent bulbs in the ceiling fixtures to 25Watts (from 32 Watts) to save some money over the long haul. They also change the color temperature from a warmer tone (maybe 2700K) to the “cool white” 4100K bulbs.

    Maybe it’s me psyching myself out, but my eyes hurt and my computer screen seems to make me squint more. So here’s my question: What is the optimal color temperature for office lighting. In regards to mood, eye strain and productivity? 2nd part of the question is: If you can’t achieve this with overhead lighting (if we’re stuck with 4100K bulbs), how can you offset with task lights? Where would they be placed and what color should they be?
    .

    yes, that’s a frequent error that occurs with lighting “upgrades.” Just because the lumen output is slightly higher for the cooler kelvin temp color ranges doesn’t make them better visually. In fact, in lighting warehouses it has been scientifically proven that the dimmer seeming yellowish light of high pressure sodium lighting makes it easier to read labels than higher lumen levels of “whiter” metal halide illumination.

    If they’ve already upgraded to electronic ballasts from the old magnetic (lord, I hope so) your problem is not likely to be 60 cycle strobing so it is likely overillumination. Another factor people fail to take into account is that the old lamps, if they are near end of life cycle, were putting out maybe 30% less light output than before they were replaced. So the new lamps are probably even brighter than they anticipated.

    Actually, the WORST lighting for modern offices, with most work being done on a computer screen, is direct overhead fluorescent, no matter what the lamp type, due to glare and veiling reflections. The recommended design is fluorescent indirect, with the lamps facing UP and the light being reflected off the ceiling for general illumination and then individual desk task lighting at or below eye level (like the small striplights that mount under cubicle overhead book cases or a swing arm PL desk lamp).

    Optimal lighting on a normal work surface for average paperwork is 50 footcandles. Once you approach 75 you’ll increase the potential for eyestrain and up to 100 and above is definite headache terrritory. Get a light meter (a cheapie from a camera store will do it) and check the desktop light level. I worked in one office that had 150 fc on the desks — those of us with photogrey glasses had them go totally dark in the office and most of the rest had to wear sunglasses (laughably, this was the sales department of an electrical supplier with a lighting design division!!) I actually developed an ulcer on one of my corneas from my contact lenses because the high light level caused squinting that made my eyeballs contract and change shape, creating a suction cup effect on the surface of my eye.

    What I’ve done in my cubicle is get the maintenance guys to REMOVE the tubes in the 2 x 4 fixture immediately above and slightly behind me and I use the strip light under my book case and a $20 PL swing arm clamp-on desk lamp from IKEA with a 13 watt 2700K lamp for doing paperwork. It works great. At first the boss b1tched because didn’t look “uniform” but I calculated what he would save per year by having the light off and he went along with it.

    There have been numerous studies that have proved that moderate levels of indirect lighting and personally controlled local task lighting create happier and more productive workers and also reduce noise levels in the office due to each work area having a more intimate feel. On the other hand, higher light levels have been associated with higher absenteeism, more distraction and more conflict in the workplace. You can see how this works at the more basic level by watching what happens in a kindergarten class when they gradually dim the lights.

    Home Office Resources

    Leave a Reply