Ultraviolet C lamps for disinfection of surfaces potentially contaminated with SARS-CoV-2 in critical hospital settings: examples of their use and some practical advice

Table 2 Irradiation times calculated with and without direct irradiance measurements

Position	Distance from the lamp^a	Angle^b	Expected irradiance from nominal data	Irradiation time corresponding to expected irradiance	Measured irradiance^c	Irradiation time corresponding to measured irradiance	Time required to compensate for the emission not immediately fully operational	Total irradiation time corresponding to measured irradiance	Difference between measured and expected time
	[m]	[°]	[μWatt/cm²]	[s]	[μWatt/cm²]	[s]	[s]	[s]
CT bed - Mobile support equipped with an AirZing™ PRO5040 lamp
Side edge of the bed	0.90	20	165	224	160	231	19	250	10.4%
Headrest	1.40	45	71	521	46	804	17	821	36.6%
Cubicle for nasopharyngeal swab - Mobile support equipped with two AirZing™ PRO5040 lamps
Medical chair	0.85	20	199	187	191	194	17	211	11.4%
Side edge of the bed	1.30	30	83	446	74	500	18	518	13.9%
Waiting room for COVID-19 triage - Two Deluxe110 lamps on the ceiling^d
First chair	1.90	0	166	223	196	189	10	199	−12.1%
Second chair	2.60	45	89	416	89	416	9	425	2.1%
Waiting room for COVID-19 triage - Two AirZing™ PRO5040 lamps on the ceiling^d
First chair	1.90	0	39	949	42	881	18	899	−5.6%
Second chair	2.60	45	21	1762	13	2846	17	2863	38.5%
Waiting room for COVID-19 triage - Two Sterilight-S72-UV-C lamps on the ceiling^d
First chair	1.90	0	61	607	109	339	13	352	−72.4%
Second chair	2.60	45	33	1121	30	1233	13	1246	10.0%
Waiting room for COVID-19 triage - Two Deluxe110 lamps on the walls^d
First chair	2.30	0	113	327	139	266	10	276	−18.5%
Second chair	4.60	45	28	1321	28	1321	9	1330	0.7%

^aThe distance is calculated from the reference position to the center of the luminous elements
^bAngle between the axis orthogonal to the luminous elements and the line joining the reference position and the center of the luminous elements
^cIrradiance measurements were made two minutes after switching on
^dIrradiance measurements were made by switching on only one lamp at a time

ISSN: 1471-2334