Table 5.

A comparison of the technical properties of UVC LEDs and mercury lamps.

Variable (Unit)	UVC Source
	LEDs	Low-Pressure Mercury Vapor Lamps	Medium-Pressure Mercury Vapor Lamps
UVC spectral width (nm)	200–280 [52]	254 [5]	200–280 [14]
Service life (h)	Up to 100,000 [52]	8000–12,000 [14]	4000–8000 [14]
Wall-plug efficiency (%)	1–3 [2]	Up to 40 [54]	10–20 [14]
Cold start time (min)	negligible [2]	4–7 [14]	1–5 [14]
Warm start time (min)	negligible [2]	2–7 [14]	4–10 [14]