A germicidal lamp system using ultraviolet light produced from more than one xenon lamp under high gas pressure and operating at a high voltage where the lamps are flashing at an interleaving mode to preserve lamp life and to reduce the exposure time while still achieving a high kill ratio of microbiota in the area exposed to the UVC light. Advantages of the disclosed germicidal flashlamp system is that it exhibits increases in UVC Peak Optical Energy, reduced Exposure Time, increased Flashlamp Life / Durability, and increased Radiation Coverage.
One of the options presented is a Portable and Cordless Three (3) flashlamp unit mounted on a hospital grade stainless steel cart, housing a rechargeable Backup Battery Power Station capable of operating the unit for 6.7 straight hours.
One of the main advantages of the lamp system UVC Disinfectant (germicidal lamps) is to provide a compact, mobile, clean, environmentally safe, and effective way to combat and kill all of the different types of pathogens that affect humanity, including COVID 19.
What is the UVC dose for killing or disabling the COVID-19 virus? Because the COVID-19 virus (SARS-CoV-2) is so new, the scientific community does not yet have a specific deactivation dosage. However, we know the dosage values for comparable viruses in the same SARS virus family are 10-20 mJ/cm2 using direct UVC light at a wavelength of 254nm. This dosage will achieve 99.9% disinfection (i.e., inactivation) under controlled lab conditions.
According to the International Ultraviolet Association, it is generally accepted that a dose of 40 mJ/cm2 of 254 nm light will kill at least 99.99% of “any pathogenic microorganism” under controlled lab conditions.
Germicidal Lamp System’s Calculations
For 640 Joules of Energy (1600 VDC anode voltage), an estimated 10 to 15% is available as UVC radiation out of the flashlamp used (Manufacturer’s Input) So, the Peak Optical Energy out of a single flashlamp is: 640 x 0.125 = 80 Joules
For 3 Flashlamps The Peak Optical Energy is = 80 x 3 = 240 Joules
Area of a sphere 3 meters in radius: 4πr2 = 4 x 3.14 x 3002 = 1.13 x 106 cm2
For 80 joules: Flux = 80/1.13 x 106 = 0.071 mJ/cm2
For a kill of 6 log, need 10 mJ/cm2: (For most hardy microorganisms)
Therefore: 10/.071 = 140 pulses @ 30 pulses / minute = 4.7 minutes @ 3 meters from the unit!. For spores at 20 mJ / cm2, this value will double.
These values will be determined empirically when a good UVC Peak Power meter be available, and also hospital and Labs tests using pathogens’ cultures.