valgusvoo ühik rahvusv. mõõtühikute süsteemis (SI). 1 lm võrdub valgusvooga, mida punktikujuline valgusallikas kiirgab ruuminurka 1 steradiaan, kui tema valgustugevus on 1 kandela.
unit of luminous flux, equal to the luminous flux per steradian emitted by a point source of one candela of uniform intensity
Manufacturers of luminaires for fluorescent lamps without integrated ballast with total lamp lumen above 2 000 lumen shall provide at least the following information on free-access websites and in other forms they deem appropriate for each of their luminaire models.
