Hi,
the expression that is used in Eletrical instalations is:
Lumens = Area* Lux*(d/n)
- d is a parameter that depends in how clean the place is, the standart for clean places is 1.25
- n is a parameter that depends on several things:
K = A/(height*(lenght+width)) -> with this value u will get the value for n in a tecnical sheet of the Bulb u are using.
But it seems too much effort just for that.
About the wavelenghts u gotta see in the bulb datasheet wich are the wavelenghts in wich it irradiates, LED's are usually very bad because they only irradiate in few wavelenghts...
Just buy 4000K(white) bulbs with the max spectre possible I guess...
Hope it helped mate