to be honest with you i dont under stand lumens standerd...when i started growin i learned to go by watt's....for every square foot you want42.5watts...this method is for people who grow with real lights ie mh/hps...to get the watts per square foot numba..you take the numba of square feet in your grow spot an divied that by the watts your light produces...also my light is 90,000 lumens...