May 16 might be “International Day of Light,” but ergonomists and office employees are usually more concerned about glare than light.
I was watching the Netflix series Beef last week and I chuckled when one character said, “Everyone loves light, by the way. There’s no human being that doesn’t love light.” It’s true; if you’re setting up a home office, you’d never put it in a room without a window. Corner offices are coveted for a reason.
But when it comes to computer work, light isn’t always our friend. We should give particular consideration to phenomena that ergonomists refer to as direct and indirect glare, which are recognized by the CSA Office Ergo standard Z412-24.
Placing you desk so that you face the window seems like a great idea. While you’re thinking about how to respond to an email, you can gaze out at the blossoming yard. You’ll have warning when a delivery is coming to the door, or the kids are coming home for lunch. But facing a window creates a high probability of direct glare, meaning bright light shining directly into your eyes. This will almost certainly cause a headache and will make it difficult to view your computer screen, so eventually you’ll have to put up light-blocking blinds. The American Optometric Association (AOA) notes that direct glare from windows is one of the most common triggers of Computer Vision Syndrome (CVS), a cluster of symptoms that includes eyestrain, headaches, and blurred vision.
Logically, you might think that rotating your workstation so your back is to the window will be better, with fewer distractions as an added bonus. But now the light reflects from your computer’s screen into your eyes, and you’ll see a vivid reflection of the window competing with the text for your attention. This is what ergonomists call indirect or reflected glare, and it produces the same outcome: headaches. Ultimately blinds might be the most practical fix.
If you have any choice about how to set up a computer, the solution is to position the screen perpendicular to the windows, so that light reflected off the screen does not meet your eyes. CSA Z412-17 recommends that windows be located to the side of workstations and that luminance ratios between the screen and its immediate surroundings be kept within a 1:3 ratio in order to reduce visual fatigue over the course of a workday.
For HR practitioners who are managing remote and hybrid workers, it is worth keeping in mind that employers’ duty of care generally extends to home office setups under general duty provisions. Document glare as a recognized ergonomics hazard and provide workers with practical guidance on workstation placement, to contribute to a defensible due diligence record should a visual health complaint arise.
Lighting is a complex topic; the amount, type, colour, and direction of light can keep an ergonomist talking for hours. Today we just talked about glare.
Need some help with your office set up? Book an office ergo assessment with one of our ergonomists.
References
CSA Z412-17 — Office Ergonomics: An Application Standard for the Management of Occupational Health and Safety — https://www.csagroup.org/store/product/CSA%20Z412-17/