Leds with UV

Growroom Design
39

You want to avoid UV-C bulbs. Those can be dangerous. If you’ve heard of blindness or eye problems from arc-flash, this is the radiation that can cause those problems. UV-C from the sun is mostly filtered by the atmosphere and we don’t really see much at the ground.

UV-B can cause some issues if you are staring at them, are using them to get a suntan, or experience significant term exposure. But, generally, much safer than UV-C particularly if you treat them with precaution.

To get a better feel for the spectra of natural light:

Sunlight, 11AM EST Northeast US. Current conditions partially cloudy.

Integral radiant (400-700nm): 341.7 W/m^2 
Integral radiant (350-840nm): 483.8 W/m^2 
Spectrometer PFD (400-700nm): 1580 umol / m^2 s
287-320nm UVB : 0.06%
320-399nm UVA : 3.06%
400-475nm Violet-Blue : 11.54%
476-550nm Cyan-Green : 16.07%
551-700nm Green-Yellow-Red : 37.17%
701-850nm Far Red-NearIR : 32.09%

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Compare this with a Fluence Spydr 2P:

Spydr 2P PhysioSpec Indoor

(open air, single point, 18" distance from center of lamp)

Integral radiant (400-700nm): 186.4 W/m^2 
Integral radiant (350-840nm): 192.3 W/m^2 
Spectrometer PFD (400-700nm): 889.56 umol / m^2 / s 
Spectrometer PFD (350-840nm): 925.5 umol / m^2 / s 
Quantum Sensor PFD (400-700nm): 850.4 umol / m^2 / s
UVB(287-320nm): 0.01%
UVA(320-400nm): 0.12%
Violet_Blue(400-475nm): 11.91%
Cyan_Green(475-550nm): 18.58%
Green_Yellow_Red(550-700nm): 65.56%
FarRed_NearIR(700-850nm): 3.82%

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Here is the Fluence UV spec bar:

Fluence RAY44 UVSpec

(open air, single point, 18" distance from center of lamp)

Integral radiant (400-700nm): 28.5 W/m^2
Integral radiant (350-840nm): 34.1 W/m^2 
PAR (400-700nm): 97.53 umol / m^2 s
287-320nm UVB : 0.02%
320-399nm UVA : 19.07%
400-475nm Violet-Blue : 80.89%
476-550nm Cyan-Green : 0.01%
551-700nm Green-Yellow-Red : 0.00%
701-850nm Far Red-NearIR : 0.00%

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That is primarily a UV-A spectra with some spread into high UV-B.

The majority of LED fixtures that have UV are going to be UV-A. Fixtures do exist that have UV-B but they are relatively uncommon, and as other have noted, the lifetime is much shorter compared to LEDs in the PAR range.

Additional examples can be found in: Lighting Spectral Data

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