Many manufacturers of illuminated LED exit signs claim a lamp life of 50,000 or even 100,000 hours, an equivalent of 5-11 years, respectively. It is important to note however, this claim is limited to only the LED component, not the associated circuity, housing, or driver. Consequently, the exit sign could reach the end of its lifecycle before the LED component does, rendering the exit sign ineffective.
Although it is uncommon for LED light sources to fail all at once, it does happen. Although what is more likely is a gradual loss of brightness over time. What the claimed life span of 50,000 hours more accurately means is the LED is likely to exhibit a gradual drop in brightness every year until, after approximately 50,000 hours it ceases to preform as rated. Moreover, some LED life expectancies are based on the time taken for the product to reach just 30% of initial brightness, which can result in an unrealistic life expectancy claims. This level of brightness may not be accepted by local building and fire codes, rendering your exit sign non-compliant and creating a potentially dangerous situation.