- Initial Lumens = total, source
- Delivered Lumens = performance, actual
Initial lumens is a measurement of the total light an LED source is producing before operational efficiency is included. This is the total amount of light coming from a light source without accounting for optics, housing and accessories. Initial lumens can also be referred to as “total” or “source” lumens.
Delivered lumens is a measurement of the actual amount of illumination (light output) a light fixture is producing in a space, including the efficiency of the reflectors, the fixture housing, accessories and other factors. This is the total amount of “useful” light that is actually exiting a lighting fixture.
Why it Matters
The reason that the delivered lumens matters is because this tells you how much light you will have to apply to your application.