UV-C dose required to kill microorganisms

Below is a list of microorganisms and the UV-C dose at 254 nm (displayed in J/m2) required to achieve a 90% (1 log reduction).

UV dose (J/m2) = UV irradiance (W/m2) x exposure time (seconds)

If you know the UV irradiance value then you can use our online UV dose calculator to determine the UV dose applied, which varies with time.

In order to calculate further log reductions, you could – as a guide – multiply the D90 value to further reduce contamination as follows:

  • D90 multiplied by 2 could provide you with a 99% (2 log) reduction
  • D90 multiplied by 3 could provide you with a 99.9% (3 log) reduction
  • D90 multiplied by 4 could provide you with a 99.99% (4 log) reduction
  • D90 multiplied by 5 could provide you with a 99.999% (5 log) reduction
  • D90 multiplied by 6 could provide you with a 99.9999% (6 log) reduction

However, it is recommended that trials and evaluation are conducted to determine the required UV dose levels required to achieve different log reductions of your target microorganisms.

Coronavirus (SARS-CoV-2)

Since the start of the SARS CoV-2 pandemic, Dr. Anthony Griffiths, Associate Professor of Microbiology at Boston University School of Medicine and his team have been working on developing tools to support scientific advancement in this field.

During their research, they have treated inoculated material with different doses of UV-C radiation and assessed the inactivation capacity under various conditions. The team applied a dose of 50 J/m2, resulting in a reduction of the SARS-CoV-2 virus of 99%. Based on the data, it was determined that a dose of 220 J/m2 will result in a reduction of 99.9999%.

“Our test results show that above a specific dose of UV-C radiation, viruses were completely inactivated; in a matter of seconds we could no longer detect any virus,” said Dr. Anthony Griffiths.

UV-C germicidal solutions for disinfection applications

Bacteria

Microbe
Type
D90
Media
Source
Acinetobacter baumannii
Veg
18 J/m2
Surface
Rastogi 2007
B. atrophaeus (B. globigii)
Sp
144 J/m2
Air
EPA 2006
Bacillius anthracis spores
Sp
743 J/m2
Surface
Knudson 1986
Bacillus cereus spores
Sp
408 J/m2
Surface
Benoit 1990
Bacillus megatherium
Sp
273 J/m2
Surface
Hercik 1937
Bacillus subtilis
Veg
14 J/m2
Air
Nakamura 1987
Bacillus subtilis spores
Sp
149 J/m2
Air
Ke 2009
Burkholderia cepacia
Veg
22 J/m2
Air
Fletcher 2004
Corynebacterium diphtheriae
Veg
33 J/m2
Surface
Sharp 1939
Escherichia coli
Veg
55 J/m2
Surface
Hollaender 1955
Escherichia coli
Veg
11 J/m2
Air
Koller 1939
Francisella tularensis
Veg
288 J/m2
Air
Beebe 1959
Haemophilus influenzae
Veg
38 J/m2
Surface
Mongold 1992
Halobacterium sp. NRC-1
Veg
25 J/m2
Surface
Crowley 2006
Legionella dumoffi
Veg
24 J/m2
Surface
Knudson 1985
Legionella bozemanii
Veg
15 J/m2
Surface
Knudson 1985
Legionella gormani
Veg
26 J/m2
Surface
Knudson 1985
Legionella jordanis
Veg
11 J/m2
Surface
Knudson 1985
Legionella longbeach
Veg
11 J/m2
Surface
Knudson 1985
Legionella micdadei
Veg
15 J/m2
Surface
Knudson 1985
Legionella oakridgensis
Veg
22 J/m2
Surface
Knudson 1985
Legionella pneumophila
Veg
5 J/m2
Surface
Knudson 1985
Legionella wadsworthii
Veg
4 J/m2
Surface
Knudson 1985
Listeria monocytogenes
Veg
156 J/m2
Surface
Kim 2002
Micrococcus candidus
Veg
61 J/m2
Surface
Hollaender 19855
Micrococcus piltonesis
Veg
81 J/m2
Surface
Rentschler 1941
Micrococcus sphaeroides
Veg
100 J/m2
Surface
Rentschler 1941
Mycobacterium bovis BCG
Veg
22 J/m2
Surface
Collins 1971
Mycobacterium bovis BCG
Veg
33 J/m2
Air
Ko 2000
Mycobacterium parafortuitum
Veg
46 J/m2
Air
Peccia 2001
Mycobacterium phlei
Veg
63 J/m2
Air
Riley 1976
Mycobacterium smegmatis
Veg
12 J/m2
Air
Gillis 1974
Mycobacterium tuberculosis
Veg
11 J/m2
Surface
Collins 1971
Mycobacterium tuberculosis
Veg
5 J/m2
Air
Riley 1976
Mycoplasma arthritidis
Veg
7 J/m2
Surface
Furness 1977
Mycoplasma fermentans
Veg
9 J/m2
Surface
Furness 1977
Mycoplasma hominis
Veg
7 J/m2
Surface
Furness 1977
Mycoplasma Orale type 1
Veg
11 J/m2
Surface
Furness 1977
Mycoplasma Orale type 2
Veg
6 J/m2
Surface
Furness 1977
Mycoplasma pheumoniae
Veg
8 J/m2
Surface
Furness 1977
Mycoplasma salivarium
Veg
11 J/m2
Surface
Furness 1977
Neisseria catarrhalis
Veg
44 J/m2
Surface
Rentschler 1941
Nocardia asteroides
Veg
280 J/m2
Surface
Chick 1963
Phytomonas tumefaciens
Veg
44 J/m2
Surface
Rentschler 1941
Proteus vulgaris
Veg
30 J/m2
Surface
Rentschler 1941
Pseudomonas aeruginosa
Veg
55 J/m2
Surface
Hollaender 1955
Pseudomonas aeruginosa
Veg
4 J/m2
Air
Sharp 1940
Pseudomonas fluorescens
Veg
35 J/m2
Surface
Rentschler 1941
Pseudomonas fluorescens
Veg
3 J/m2
Air
van Osdell 2002
Salmonella enteritidis
Veg
10 J/m2
Surface
Collins 1971
Salmonella typhi
Veg
21 J/m2
Surface
Sharp 1939
Sarcina lutea
Veg
197 J/m2
Surface
Rentschler 1941
Serratia indica
Veg
209 J/m2
Air
Harstad 1954
Serratia marcescens
Veg
22 J/m2
Surface
Sharp 1939
Serratia marcescens
Veg
115 J/m2
Air
Ko 2000
Shigella paradysenteriae
Veg
17 J/m2
Surface
Sharp 1939
Spirillum rubrum
Veg
44 J/m2
Surface
Rentschler 1941
Staphylococcus albus
Veg
33 J/m2
Surface
Rentschler 1941
Staphylococcus albus (1)
Veg
23 J/m2
Air
Rentschler 1942
Staphylococcus albus (2)
Veg
52 J/m2
Air
Rentschler 1942
Staphylococcus aureus
Veg
66 J/m2
Surface
Gates 1934
Staphylococcus aureus
Veg
20 J/m2
Air
Nakamura 1987
Staphylococcus epidermis
Veg
29 J/m2
Air
van Osdell 2002
Streptococcus agalactiae
Veg
5 J/m2
Air
Luckiesh 1949
Streptococcus haemolyticus
Veg
22 J/m2
Surface
Sharp 1939
Streptococcus pneumoniae
Veg
468 J/m2
Surface
Gritz 1990
Streptococcus pyogenes
Veg
4 J/m2
Surface
Lidwell 1950
Streptococcus pyogenes
Veg
1 J/m2
Air
Luckiesh 1949
Stroptococcus viridans
Veg
20 J/m2
Surface
Sharp 1939

Viruses

Microbe
Type
D90
Media
Source
Adenovirus
dsDNA
59 J/m2
Air
Walker 2007
Adenovirus type 2
dsDNA
400 J/m2
Surface
Day 1974
Adenovirus type 40
dsDNA
300 J/m2
Surface
Meng 1996
Adenovirus type 41
dsDNA
240 J/m2
Surface
Meng 1996
Bacteriophage MS2
dsRNA
61 J/m2
Air
Walker 2007
Bacteriophage MS2
dsRNA
4 J/m2
Air
Tseng 2005
Coliphage X-174
dsDNA
4 J/m2
Air
Tseng 2005
Coliphage PRD1
dsDNA
87 J/m2
Surface
Meng 1996
Coliphage T7
dsDNA
10 J/m2
Air
Tseng 2005
Coronavirus
ssRNA
3 J/m2
Air
Walker 2007
Coxsackievirus
ssRNA
21 J/m2
Air
Jensen 1964
Human Cytomegalovirus
dsDNA
658 J/m2
Surface
Albrecht 1974
Influenza A virus
ssRNA
19 J/m2
Air
Jensen 1964
Newcastle Disease Virus
ssRNA
16 J/m2
Surface
Rubin 1959
phage phi 6
dsRNA
7 J/m2
Air
Tseng 2005
Poliovirus
dsRNA
44 J/m2
Surface
Ma 1994
Poloiovirus type 1
dsRNA
41 J/m2
Surface
Meng 1996
Rauscher Murine Leukemia v.
ssRNA
959 J/m2
Surface
Stull 1976
Rous Sarcoma virus (RSV)
ssRNA
200 J/m2
Surface
Rubin 1959
Sindbis virus
ssRNA
62 J/m2
Air
Jensen 1964
S. aureus phage
ssDNA
82 J/m2
Surface
Gates 1934
Vaccina virus
ssDNA
15 J/m2
Air
Jensen 1964