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Table 1 Decimal reduction times (D-values) for the bacteria in different chemical agent solutions.

From: Determination of decimal reduction time (D value) of chemical agents used in hospitals for disinfection purposes

Bacteria Disinfectant concentration Survivors1 D value 2t = n × D 2t = n × D
  (%) (mg/L) logN (min) 3n = 6-log10 n = 12-log10
      (min) (min)
SODIUM DICHLORO ISOCYANURATE(pH = 7.0)       
A. calcoaceticus 0.1 1000 -0.17t 5.9 35.4 70.8
E. cloacae 0.1 1000 -0.21t 4.7 28.2 56.4
E. coli 0.1 1000 -0.17t 5.9 35.4 70.8
S. aureus 0.1 1000 -0.20t 5.0 30.0 60
S. marcescens 0.1 1000 -0.23t 4.3 25.8 51.6
B. stearothermophilus 0.2 2000 -0.22t 4.4 26.6 53.3
B. subtilis 0.2 2000 -0.26t 3.8 22.5 45
SODIUM HYPOCHLORITE (pH = 7.0)       
E. coli 0.05 500 -0.16t 6.1 36.4 72.9
B. stearothermophilus 0.05 500 -0.106t 9.4 56.4 112.8
B. subtilis 0.05 500 -0.097t 10.3 61.8 123.6
B. stearothermophilus 0.1 1000 -0.28t 3.5 20.9 41.8
B. subtilis 0.1 1000 -0.31t 3.2 19.2 38.3
SODIUM HYPOCHLORITE(pH = 7.0)       
A. calcoaceticus 0.025 250 -0.16t 6.2 37.3 74.6
E. cloacae 0.025 250 -0.13t 7.5 44.8 89.6
E. coli 0.025 250 -0.13t 7.5 45.1 90.1
S. aureus 0.025 250 -0.21t 4.7 27.9 55.8
S. marcescens 0.025 250 -0.149t 6.7 40.1 80.2
B. stearothermophilus 0.025 250 -0.041t 24.0 144.0 288.0
B. subtilis 0.025 250 -0.048t 20.6 123.6 247.2
GLUTARALDEHYDE(pH = 7.4)       
A. calcoaceticus 2.0 20000 -0.21t 4.7 28.2 56.4
E. cloacae 2.0 20000 -0.15t 6.7 40.2 80.4
E. coli 2.0 20000 -0.14t 7.1 42.6 85.2
S. aureus 2.0 20000 -0.17t 5.9 35.4 70.8
S. marcescens 2.0 20000 -0.20t 5.0 30.0 60.0
B. stearothermophilus 2.0 20000 -0.04t 25.0 150.0 300.0
B. subtilis 2.0 20000 -0.04t 25.0 150.0 300.0
FORMALDEHYDE(pH = 6.5)       
A. calcoaceticus 0.5 5000 -0.19t 5.2 31.2 62.4
E. cloacae 0.5 5000 -0.22t 4.5 27.0 54
S. marcescens 0.5 5000 -0.48t 2.1 12.6 25.2
B. stearothermophilus 0.5 5000 -0.10t 10.9 65.4 130.8
B. subtilis 0.5 5000 -0.13t 11.8 70.8 141.6
CHLORHEXIDINE(pH = 6.2)       
A. calcoaceticus 0.4 4000 -0.24t 4.1 24.6 49.2
E. cloacae 0.4 4000 -0.12t 8.3 49.8 99.6
E. coli 0.4 4000 -0.34t 3.0 18.0 36.0
S. aureus 0.4 4000 -0.17t 5.9 35.4 70.8
S. marcescens 0.4 4000 -0.25t 4.0 24.0 48.0
B. stearothermophilus 2.0 20000 -0.11t 9.1 54.6 109.2
B. subtilis 2.0 20000 -0.15t 6.7 40.2 80.4
MINNCARE 5 (pH = 2.3)       
A. calcoaceticus 1.0 10000 -0.30t 3.4 20.4 40.8
E. cloacae 1.0 10000 -0.29t 3.5 21.0 42.0
E. coli 1.0 10000 -0.15t 6.7 40.2 80.4
S. aureus 1.0 10000 -0.25t 4.0 24.0 48.0
S. marcescens 1.0 10000 -0.28t 3.6 21.6 43.2
B. stearothermophilus 1.0 10000 -0.11t 9.1 54.6 109.2
B. subtilis 1.0 10000 -0.17t 5.9 35.4 70.8
HYDROGEN PEROXIDE(pH = 3.3)       
E. cloacae 1.5 15000 -0.56t 1.8 10.8 21.6
E. coli 1.5 15000 -0.31t 3.2 19.2 38.4
S. aureus 1.5 15000 -0.30t 3.4 20.4 40.8
B. stearothermophilus 26.5 265000 -0.21t 4.7 28.2 56.4
B. subtilis 1.5 15000 -0.02t 55.2 331.2 662.4
  1. 1 Survivor Curve: log Nf = log No-1/D × t; No= bioburden; Nf= survival population; D-value = decimal reduction time; (-1/D) = slope. 2 t = n × D, where: t = total exposure time (min); n = log10 reduced cycles 3 t = n*D and n = 6-log10, t = the exposure time for a 6-log10 reduction in the bioburden (No) with a defined D-value4 t = n*D and n = 12-log10, t = the exposure time for a 12-log10 reduction in the bioburden (No) with a defined D-value 5MINNCARE = 0.45 % peracetic acid + 2.2 % hydrogen peroxide
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BMC Infectious Diseases

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