Product efficacy: Refer to existing lighting program requirements to set minimum efficacy criteria, then screen product options against those needs.
Light delivery: Ensure that the replacement will provide appropriate lighting for the tasks in each space. You may have to measure the existing conditions or conduct modeling exercises to make sure post-retrofit light levels are reasonable.
Light distribution: LEDs are directional, unlike fluorescent lamps, which can create uneven, unappealing light patterns.
Product useful life: The replacement should last as long or longer than the existing lamp. Many LEDs have the potential to last longer than fluorescent lamps and are typically rated with high lifetimes, but before you take the plunge, consider whether that long life will actually be used. If the space may be reconfigured soon or has a low lighting use time, a very long-life product may not be worth it.
Lighting color: LEDs come in color temperatures similar to fluorescent lamps. The GSA recommends choosing LED lamps with the same color temperature as the previous fluorescent lamps.
Installation time and cost: LED direct lamp replacements cost more than fluorescent lamps and the labor costs can vary widely. Depending on how much rewiring is needed, a new LED fixture might be just as affordable as a replacement kit.
Installation capability: Make sure the existing system has the right ballast type to operate the LEDs – usually an electronic instant-start. Determine whether the existing optical system is easily removable, how the ballast is accessible and how difficult it is to access, what type of ballast is required and how many sockets are installed.
Maintenance: Longer lifetimes mean significant savings from fewer replacements, so include reduced maintenance in cost & budget proposals.