The ESP doesn't emit light in the assumed low end wavelength where UVs are normally present. According to Graeme Gill colour scientist there can be some spikes in other regions but it's a moving target that would have much less chance of incidence outside of the <430 nm range.
So a normal spectro , i.e., gas filled tungsten has to have a an optic filter but LED can be made so with selection of narrow band LEDs in essence a filtration making a largely reduced UV emission hence UV cut.
I believe on the IsIs automated X-Rite spectro there are both narrow and wider LEDs so booth UV cut and UV readings are possible.
