GB2603449A - High intensity UVC air sterilization system - Google Patents

Abstract

An air sterilisation system utilising a UV source 7, having a blower 8 which pulls air into the system through a pre-filter 9, where air is funnelled 6 into an irradiation zone 5 having a reflective coating 6 and which expels air out of the system via a divergent 2 exhaust 1. This enables more effective sterilization of air. The system may multiple UV sources arranged sequentially (Fig 3) to increase the pathogen exposure time. The source may emit specifically UVC light, and more specifically light of 254nm wavelength. The system may have a display (1; Fig 5) for showing UV intensity and/or fan speed and enables control of said intensity and fan speed. The system may therefore be efficacy tuned to destroy a pathogen of the user’s choosing. The system may perform shutdown and provide a warning signal to the user based on malfunction, tampering and/or opening of the device casing.

Description

INTELLECTUAL PROPERTY OFFICE (IPO) UNITED KINGDOM (Provisional Utility Patent Application) TITLE: HIGH INTENSITY UVC AIR STERILIZATION SYSTEM Application No: GB2016126.1 INVENTOR: Paul Byrne ABSTRACT: A summary of all the important technical aspects of the invention and by their reference are made part of this application

NOMENCLATURE

For the purpose of this document, the following naming conventions will be used: 1. The Power of a UVC Lamp is measured in Watts (W) 2. The Energy of UVC Light Flux is measured in joules (J/j) 3. Energy Density is measured in pj/cm2 (micro-joules/centimetre squared) 4. Power Density is measured in pW/cm2 (micro-Watts/centimetre squared) 5. Microorganisms include several distinct groups of disease causing germs, namely Viruses, Bacteria, Fungi, Algae and Protozoa.

6. The term Pathogen will referrer to those microorganisms such as Viruses and Bacteria as these are the microorganisms of interest in this invention. However, this invention is not limited to this definition.

7. Dose: The amount of UVC Energy Density (pj/cm2) normal to the direction of flow required to destroy a pathogen.

8. Power Reference Distance: The distance that a given UVC Source Power Density is measured.

9. UV Irradiance: The radiant power, within a stated wavelength range, arriving at a surface. It is measured in pW/cm2 Flux: The flow of UV Irradiance arriving on a surface area perpendicular to photon flux

FIELD OF THE INVENTION:

[0001] The current embodiment is a method of increasing the intensity of the irradiance of UVC light (Flux) ard ensuring that all of the air volume in a room (Room Space) is sterilized so as to ensure that pathogens such as viruses and bacteria are rendered harmless or destroyed. More particularly, the invention defines Room Space as being:: * Hospital Patient Room such as a Patients Room, common area or ICU critical care environment.

* Restaurants, Airports, Offices, Factories, libraries, Schools * Any other area where people gather.

BACKGROUND:

[0002] UVC Light has been used for Sterilizing surfaces from Bacteria, Viruses and other pathogen since the mid-20th Century. In order for damage to occur to these and other Pathogens, certain criteria must oe understood and enacted.

UV Light is a portion of the Elect-o-Magnetic-Spectrum. Classification for the visible and UV portion of this spectrum is classified according to the Draft Standard: ISO-DIS-21348.

[0003] For this embodiment, the portion of interest within the UV Spectrum is further classified as UVA, UVB and UVC. It is the UVC wavelengths between 266-279 nanometres (nm) and specifically 254 nm that have been shown to have greater efficacy for rendering viruses, bacteria and other pathogens harmless or destroyed. UVC-254 works because this wavelength oenetrates through the cell and is absorbed by the nucleic acids. A rearrangement of the genetic information occurs, inactivating the Pathogen.

0004] In order for this WC light irradiance to be effective, it is necessary to understand that it is the DOSE that affects efficacy to destroy pathogens. The DOSE has three components: 1. The Power Density of the Source measured in pW/cm2 micro-watts/centimetre squared 2. The distance to the Pathogens are from the Source (meters) 3. The length of time the Pethocens are exposure to the UVC Light (seconds) For any system to be effective, it would be advantageous for the exposure time to be short and if possible, the exposure time should be in the order of seconds.

BRIEF SUMMARY OF THE INVENTION:

[0005] Because the effectiveness of the 1JVC exposure depends upon these three factors Irradiance flux of the Source (Power), the distance from the Source (meters) and the Pathogen exposure time (seconds). Increasing either or all of them will increase the Germicidal efficiency the destruction effectiveness against the pathogens.

[0006] The Power of the source is physically limited by the type and physical properties and is typically 100uW/cm2 measured at 1-meter distance from the Source. The efficacy at destroying pathogens becomes effective with energies greater than 8,000 pj./cm2 (micro Joules per square centimetre) by the U.S. Environmental Protection Agency. The distance from the Source to the Pathogers and the Time of UVC Light exposure (Residence Time) governs the effectiveness at destroying the Pathogens.

[0007] As there is nothing to be gained in waiting a long time for the pathogen to be destroyed, moving the pathogens closer to the Source would be extremely effective because the UVC Flux increases by the Inverse Square Law.

[0008] Most environments where pathogens cause a threat are Room Spaces and other confined areas where people congregate. Having a Source situated somewhere inside a space, would have a wide range of effectiveness. The pathogens very close to the Source would be destroyed immediately, while other pathogens further away, might not be effected at all; this is because their exposure time was too low.

[0009] Having UVC Sources exposed in the open can also pose a serious health risk to human beings causing skin defo-mations, cancer and blindness. The Current Invention solves these issues.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 shows the main elements of the Invention: [0011] Description of Figure 1: * [1](Fig1)-The exhaust of the sterilized air, which can be elevated if needed * [2](Fig1)-The Divergent Section of the High Reflectivity Zone reducing air velocity * [3](Fig1)-The High Flux Zone. The area of concentrated UVC Power Density * [4) ](Fig1)-The High Reflectivity Materials on the inside of the Void * [5](Fig1)-The High Irradiance Flux Zone (Void) * [6] (Fig1)-The Convergent Section of the High Reflectivity Zone * [7](Fig1)-The High Powe-UVC Source * [8](Fig1)-The variable Fcrced Air Mechanism (Fan) * [9](Fig1)-The inlet Pre-Filter for the air containing the Pathogens [0012] Figure 2 shows the elements of the High Irradiance Flux Zone (Void):

[0013] Description of Figure 2:

[1](Fig2) High Power UVC Source [2](Fig2) The High Irradiance Flux Zone Outer Wall [3](Fig2) The High Flux Zone. The area of concentrated UVC Power Density [4](Fig2) The High Flux Zone-Radial Distance "y" [5](Fig2) Air Volume Flow (m3/hour) [8](Fig2) Power Reference Distance (Distance the Source Power ifs qualified) [0014] Figure 3 shows the methods to lengthen the UVC Source [0015] Description of Figure 3: [1J(Fig3) Air Discharge Port [2](F1g3) High Power UVC Source [3] (Fig3) Air Cross-Flow Port [4] (Fig3) Air Inlet Port [a] (Fig3) Configuration of the High Power UVC Source can be connected vertically or horizontally to increase the overall Source Length [b] (Fig3) Configuration of the High Power UVC Source can be connected in a triangular form horizontally to increase the overall Source Length [c] (Fig3) Configuration of the High Power UVC Source can be connected in a square or Cubic Form horizontally to increase the overall Source Length [0016] Figure 4 shows a Wall Mounted embodiment. [0017] Description of Figure4: [1](Fig4) Sterile air venting into a Room Space [2](F1g4) Body of the Unit [3] (Fig4) Air Blower-Adjustable Speed [4] (Fig4) Untreated infected air inlet vent [5] (Fig4) Corner attachment bracket [6] (F194) High Power UVC Source-View from the top [7] (Fig4) Pre-Filter to catch unwanted contamination such as Leaves, Paper, String or any other floor items that might enter into the system. It is not intended to filter Pathogens, just objects that might cause damage to the Blower Module.

[8] (Fig4) Top Exit Grill-There can be many configurations. depending on customer's needs such as an extension to ceiling height.

[0018] Figure 5 shows the description of the Electronic Control Module (ECM) [0019] Description of Figures [1](F1g5) The User Interface Display that shows to the User important information regarding the Configuration and Operation of the Invention [2](Fig5) The Micro-Controller that controls the operation of the Invention [3](Fig5) The Current Sensor. This sensor reads the electrical current running through the Blower which is then read by the computer. This current allows the Micro-Controller to determine if the Blower is operat ng ON or OFF and is within operational parameters.

[4](Fig5) Power Relay. This relay activates the Power Control for the Invention [6](Fig5) Signal Conditioning Module. This module conditions the electronic measurements for the invention, including: 1. Blower Status 2. UVC Lamp Status 3. Open Panel Security: If any part of the structure of the invention is opened or tampered, this will be reported to the Micro-Controller for Shut-Down 4. Motor Temperature 5. UVC Lamp Temperature 6. Out-of-Specification for all electroric parameters [7](Fig5) Main Terminal Blcck: The location for all interconnections of the electrical components and subsystems, including safety fuses and circuit breakers.

[0020] Figure 6 shows three UVC Sources configured in parallel [0021] Description of Figure 6 [1](Fig6) The High Reflectivity Materials on the inside of the Void [2](Fig6) The High Irradiance Flux Zone (Void) [3](Fig6) The High Power UVC Source [4](Fig6) The inner High Reflectivity Material

DETAILED DESCRIPTION OF THE INVENTION

[0022] Most infections are caused by breathing pathogen contaminated air. When a source of High Power UVC light is located inside a Room Space, there would be a varying degrees of effectiveness in destroying these pathogens that are being irradiated. Those close to the source, would be effected the most, while others further away would be affected the least. These effects are not linear with distance but rather vary with the Inverse Square Law.

[0023] There are four aspects to this problem that need to be addressed. The current embodiment of the Invention solves all four; these being: a) How to effectively expose all of the pathogens in a Room Space.

b) How to bring the Pathogens close to the source to be destroyed c) How to control the Residency Time (the time of exposure) so that the pathogens are destroyed and rendered inert.

d) How to adjust the Power Density for specific Pathogens [0024] The current embodiment of the invention comprises four compartments: 1. A variable speed Blower-Lower Blower Module 2. A high Flux Concentrator-The area at the discharge of the Blower 3. High Reflectivity Zone-A highly reflective zone that continuously reflects the UVC Light energy back into this zone so that the UVC Light Flux is not lost.

4. A Divergent Zone, lowers the sterilized air velocity so that it cal be discharged back into the Room Space, less noticeable.

[0025] Fig 1. of this embodiment shows the full assembly of the Invention. Air is drawn into this region through a Pre-Filter Area [9](Fig1) . This Pre-Filter is designed to prevent large objects from being drawn into the Forced Air Mechanism [8](Fig1) that might cause damage to the Blower mechanism.

[0026] Fig 1. of this embodiment shows how the air being discharged from the Forced Air Mechanism through a Convergent Pathway [6](Fig1) and concentrated into a narrow Void [5](Fig1) . This Void can be any shape circular or any polygon. The reason for this convergence is to bring the patiogen laden air close to the radiant source of the High Energy UVC Light [7](Fig1) . The closer the air is drawn to this UVC Source, the more lethal it will become to the pathogens. This distance [4](Fig2) is specific to the particular Device Model Number. The closer the air is drawn to the UVC Source, the more lethal it will become to the Pathogens.

[0027] Fig 1. of this embodiment comprises of a long High UVC Flux Zone [5](Fig1). Inside this Zone is located a high power UVC light source [7] (Fig1). This Source is located in the centre of Zone [5] (Fig1) whici is covered with a Highly Reflective coating [4](Fig1) . This coating reflects the UVC Light back into the Cavity [5] (Figl) so that no UVC light is lost from disrupting the Pathogens.

[0028] At the end of Cavity [5] (Fig1) , there is a Divergent Zone [2] (Fig1) . Because this Divergent Zone [2] (Fig1) increases the cross sectional area of the air flow, the discharge velocity through the Vent [1] (Fig1) is reduced, lowering air the velocity, maKing it less noticeable outside the invention.

RESIDENCY TIME: [0029] As the Pathogens travel alorg the Void [5] (Fig1), they remain in the High Flux Zone where the high energy UVC light irradiates the Pathogens at a maximum level of lethality. Increasing this travel distance will increase the Residence Time that the Pathogens are being exposed. If the Void [5] (Fig1) cross-section is increased this will also slow the linear velocity within this Void and will cause the Residence Time to increase and deliver more destructive energy 70 the Pathogens. However, increasing the cross-sectional area of the Void will also reduce the Power/unit area of the UVC Light source, which will require more Residency Time. The relationship between these factors will determine the physical properties of the Invention and therefore the relationships for optimum efficacy to destroy the Pathogens and sterilize the air.

VARIABLE PARAMETERS AND INTERACTIONS

[0030] With reference to Figure 2. This figffe shows a Side Elevation and End Elevation of the "High Flux Zone" of Fig 1 in more detail.

[0031] Description of parts in Fig 2:

a) Item [1] (Fig2) is the High UVC source b) Item [2] (Fig2) is the Diameter of the High Irradiance Flux Zone c) Item [3] (Fig2) is the Higt. Irradiance Flux Zone d) Item [4] is the distance between the outside surface or item [1] (Fig2) and the inside surface of item [2] (Fig2) e) Item [5] (Fig2) is the volume of air flow (Q) through item [3] (Fig2) measured in (m3/hr) f) Item [6] (Fig2) is the Power Reference Distance SYSTEM RELATIONSHIPS [0032] In order to inactivate (des:roy) a Pathogen, it must be exposed to UVC light with a wavelength of 254 Nano-meters (nm) for a sufficient amount of time. This time (Residence Time) varies with each Pathogen. The physical makeup of bacteria and viruses are different and therefore take a different Dose for them to be inactivated or destroyed. This Dose is specific to each Pathogen the user of the invention wishes to treat.

[0033] UVC Power for any specific source is quoted by the manufacturer measured at a test distance. This distance is usually 1-meter from the source surface. This value is dependent on the wattage of the source and other variables, but is typically 100pW/crin2© 1-meter. The Dose required to inactivate a Pathogen is measured in micro Joules/cm2 so time (Residence Time) must be included.

[0034] These relationships apply: a) For an INCREASE in Dose, or Energy Density measured in pj/cm2 a. The distance [4](F1g2), distance 'y' must decrease, and/or b. Length L [7](Fig2) must increase, and/or c. Volume flow 0 [5](Fig2) must decrease b) For a DECREASE in Dose a. The distance [4](Fig2) must increase, and/or b. Length L [7](Fig2) must decrease, and/or c. Volume flow Q [5](Fig2) must increase [0035] By adjusting these relationships a range of Dose between 10,000pj/cm2 to 5,000,000pj/cm2 can be achieved by the use of this invention. This range of Pathogen destruction varies with each individual Pathogen. The percentage of effectiveness is presented as: 1. 90.000% reduction of Pathogen-single Log 2. 99.00% reduction of Pathogen-two Log 3. 99.900% reduction of Pathogen-three Log 4. 99.990% reduction of Pathogen-four Log 5. 99.999% reduction of Pathogen-five Log [0036] For this embodiment, a Software Algorithms have been designed and developed to indicate to the User the exact value of Energy Density Flux currently operating within the High Irradiance Flux Zone region Item [3] (F1g2). The User can then decide based on any particular "Pathogen Data of Interest" what Dose needs to be set by this invention to destroy any Pathogen. This will ensure that any and all Pathogen can be effectively destroyed, providing sterilized clean air to breath. By varying the Air Velocity through the High Irradiance Flux Zone [3] (Fig2), this Flux can be adjusted between 10,000 pj/cm2 to 5,000,000 pj/cm2. At the time of this writing, there are no known Pathogens that can survive this degree of Energy Density Flux of UVC Light.

VARYING THE LENGTH OF THE HIGH IRRADIANCE FLUX ZONE

[0037] There are four configurations shown in Fig3 that can increase the length of the High Energy UVC Sources. For this embodiment, these sources are comprised of Long Glass Tubes containing UVC generating apparatus. There are filter coatings applied to the glass to prevent the production of Ozone Gas as this gas production would not be beneficial for the required germicidal effect against Pathogens. Ozone is also deleterious to human lungs and should be avoided.

[0038] [a](F1g3) shows one embodiment where the overall length of the UVC Source can be extended to three times the length of a single source. This embodiment locates the individual UVC sources in a Linear Orientation either vertical or horizontal.

[0039] [lo](Fi93) shows one embodiment where the overall length of the UVC Source can be extended to three times the length of a single source. This embodiment locates the individual UVC sources in a triargular Orientation which takes up less space.

[0040] [c1(Fig3) shows one embodiment where the overall length of the UVC Source can be extended to three times the length of a single source. This embodiment locates the individual UVC sources in a Cubic Orientation which takes up less space.

[0041] It should be noted that these embodiments are not limited to three sources. The number of sources can be of any number within practical limitations.

DETAILED OPERATION OF THE INVENTION -Reference to Figure 1 [0042] There are many physical configurations of this invention. All of the variations rely on the same fundamental elements common to all configurations as follows: 1. There exists a High Energy UVC source [7](Figl) that provides the UVC Light Flux at the wavelength of 254 nm (nano-meters). It is this flux that destroys the Pathogens.

2. There exists a Variable Speed Blower (fan) [8](Figl) that draws air from the Room Space into this embodiment through a Pre-Filter [9] (Fig1) that catches large objects that might cause damage to the Blower Mechanism [81(Fig1) 3. Air travels through the Blower and into the Convergent Section [6] (Fig1). This section forces the contaminated air closer to the High Power UVC source [5](Fig1) destroying the Pathogens. The closer the Pathogens are to the UVC Source, the less Residency Time is required.

4. The Contaminated Air then passes into the High Flux Zone [3][5](Fig1) and travels along the High Power UVC Source [7](Fig1). The system is configured to destroy the Pathogens before they reach the end of the High Power UVC Source [7](Fig1).

5. The now sterile Air is expanded in the Divergent Section [2](Figl) slowing down the Air velocity so it can be discharged quietly into the Room Space.

6. The Sterile Air is discharged through the Exit Vent [1](Figl) which can be chosen to vent the Sterile Air in any direction or height, according to the Users Wishes_ 7. Extensions can also be attached to the top of the Vent Discharge so that the vented Sterile Air can be discharged at an elevated height close to the ceiling.

ELECTRONIC CONTROL Module (ECM} [0043] There exists in this embodiment an Electronic Control Module (ECM). This ECM will enable the User to alter how this invention operates. The operation of this Invention will provide, but not limited to, the following functions: 1) START: The ability to start operation 2) STOP: The ability to STOP operation 3) INCREASE AIR VOLUME FLOW: Increase the air volume flow by increasing the Blower Rotational speed.

4) DECREASE AIR VOLUME FLOW: Decrease the air volume flow by reducing the Blower Rotational speed.

5) DISPLAY OPERATIONAL PARAMETERS: a. Air Volume Flow in M3/hour, CFM b. Other1, Other2, O1her3 (Other1, 2 & 3 custom values by the User) c. RPM of the Blower d. Operational Status of the installed UVC Sources e. Operational Status of the UVC Source Power Supplies f. The Current value of Energy Density in millijoule per centimetre squared (mj/cm2). This will enable the User to adjust the Air Volume Flow to destroy the Pathogen of iiterest. The available range will be determined by the physical configuration of the UVC Sources and the parameters of the High Irradiance Flux Zone for the particular Model of Invention.

g. Lamp Failure Status, indicating UVC Sources operation.

h. Run-Time of the Blower and the UVC Sources in Total Run Time Hours i. Date/Time for programmable ON/OFF times j. Blower Current k. UVC Source Current I. System operating parameters m. Alarm conditions of open PaleIs or Security Ingress while the system is operating. This will cause a total system shutdown to protect users from harm.

Claims (1)

1. CLAIMS: The invention claimed is: 1) A UVC Source is used to develop High Power UVC Light that is emitting UVC Light at a wavelength of 254 nm (nanometres) 2) A blower is used to draw Pathogen contaminated air through a Pre-Filter. This Pre-Filter is used to prevent large particles from entering the system 3) The Pathogen contaminated air is forced into a Divergent Zone that will increase the power of the UVC Source to lethal levels to destroy Pathogens 4) The length of time the Pathogens are irradiated with UVC Light (Residency Time) can be controlled by adjusting the Volume Flow Rate by the use of a Blower or other Forced Air mechanism 5) The Physical length of the UVC Source can be increased by utilizing multiple individual Sources in Series to control the Pathogen Exposure Time (Residency Time) 6) Multiple UVC Sources can be used in parallel to increase the power of the combined source 7) Multiple UVC Sources can be used in parallel to increase the power of the combined sources 8) A highly Reflective material is used to reflect the UVC Light back into the Irradiation High Flux Zone 9) Reflective materials are located on surfaces to protect them from UVC Light 10) A Mathematical Algorithm is used so that within the capabilities of any model of the invention, the current efficacy of destruction can be displayed to the User 11) A User to see the current Energy Value in mj/cm2 being generated that will destroy the intended Pathogen.12) The user can 'Efficacy Tune' the invention to destroy any Pathogen of their choosing.13) A Divergent section is used to reduce the Air Velocity so that it will be less noticeable when the sterilized air re-enters the Room Space 14) Two sections are used together. The 'Lower Section' containing the Forced Air Mover (Blower) and Pre-Filter and the Upper Section that houses the UVC Sources.15) Different configurations of Air Volume Rate and UVC Power Density can be chosen interchangeably.16) The height of the Upper Section can be increased to raise the Air Discharge Vent height if required 17) Safety Interlocks are used so that if any part of the system is tampered with while in operation, the system will shut down and need to be re-started.18) If any party of the system is opened or inoperable, the system will either not start of will stop running.19) An Audible alarm will sound and the display will show the Fault Condition Mode causing the shutdown if an alarm condition occurs.