Lifetime Ratings of LEDs. If you’re not familiar with LED lighting, one fundamental way that they differ from traditional lighting is that their light is measured in lumens instead of watts. More accurately, a lumen is “a unit of luminous flux in the International System of Units, that is equal to the amount of light given out through a solid angle by a source of one candela intensity radiating equally in all directions.” Watts, on the other hand, are a measurement of the energy used by a bulb.
Because LED lighting is more energy-efficient than incandescent bulbs, the watts will be lower and not indicative of brightness. Industrial and commercial facilities often need a minimum level of lighting brightness in order to keep employees and visitors safe, which means working with an experienced distributor that can help you simplify the process of choosing lighting that’s right for the application intended.
Another of the biggest reasons to upgrade to LED lighting is the return on investment over its lifetime because of that energy efficiency. An important consideration when looking at cost is understanding how long LEDs last at the output expected or promised. While no lighting can last forever, a simple calculation can help you predict when your LED lighting is ready to be replaced — this is called a lighting maintenance factor.
Different factors impact a decrease in lighting levels, like surface soiling, lamp failure, and depreciation of luminous flux. The first day you use your new LED lights, the output should be at 100% but decreases over the thousands of hours it’s being used in your facility. This estimated decrease is used to help differentiate LED options and get you a better fit for your needs.
There was a time when many standard regulations within the LED marketplace didn’t exist, which means manufacturers can make a variety of claims about the lifetime of their products and overall performance. In order to level the playing field, government agencies, lighting standards organizations and some of the bigger manufacturers have come together to create best practices to help evaluate and compare LED products.
LM-80 is one of these standards and refers to the lumen depreciation of LED products. Before this standard was created, manufacturers would test independently and without guidelines, which led to plenty of confusion for customers who are looking to compare lighting maintenance factors. Keep in mind that this is not the only (or best) way to determine the lifetime of LEDs, but it is a useful tool.
This standard is used to describe the measurement of how the light source performs over time and under a specified set of conditions. Remember that fixtures, housing, applications, and facility environment also play a major role in the longevity of LEDs so LM-80 should not act as a be-all, end-all calculation to figure the overall lifetime — despite what some shady manufactures might tell you.
LM-80 was developed by the Illuminating Engineering Society of North America (IESNA) specifically. Typically it’s a test that lasts from 6000-10,000 hours and shows how the depreciation goes from 100% to 80% output and at what point in time it happens. Numbers are tested at operating temperatures of 55 degrees, 85 degrees, and a third manufacturer defined temperature. This testing should be performed by EPA recognized labs and only reports from these labs are considered relevant. LM-80 is used to determine eligibility for the Department Of Energy (DOE) ENERGY STAR program.
While it’s important to make an LED choice based on how long it will last, it’s just as important to understand how long it will last at the lumen level you need. It’s not just brightness that’s impacted over time; it’s also color and warmth that can shift as the LEDs get older. While a depreciation in output isn’t necessarily a big deal in buildings like warehouses or distribution centers, other facilities like museums or art galleries will notice a shift.
Knowing when you’ll likely have to replace lighting helps a great deal when optimizing facility maintenance strategies. When you plan accordingly, you’ll be able to schedule downtime for replacements, budget accordingly, and avoid unwanted disruptions or cost surprises.
If you’re just beginning with researching the best LED options for your update, it can be overwhelming. There are many reasons to work with LED lighting upgrades specialists. Once you understand them, as well as your many commercial lighting choices, you’ll be much better prepared. We don’t leave you to figure it all out on your own. We’re here to hold your hand and explain all your options so you can choose what works best for you.