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UVGI Principles of Design & Installation

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1 UVGI Principles of Design & Installation
Successfully differentiate UVGI deign concepts and apply guideline principles Tobias van Reenen

2 Contents Background Safety Application Metrology
Planning & Procurement Design Installation & Commissioning Maintenance & Monitoring Decommissioning

3 BACKGROUND UVGI uses UV-C (deep UV) to inactivate airborne microbial organisms.

4 BACKGROUND Multiple studies have shown that an 80% reduction in TB transmission can be achieved using Upper Room-UVGI

5 BACKGROUND Specification Design Maintenance Supply
50-100k UVGI devices installed in South Africa (actual number unknown) A 2012 CSIR study found that less than 5% of systems were functional. Problems were found with: Specification Design Maintenance Supply

6 BACKGROUND In 2013, the NDoH implemented a moratorium on the procurement of upper room UVGI for SA Healthcare facilities until: Design, Implementation and Maintenance guide ( Implementation of mandatory needs and risk assessments before procurement. (The guide) Device Technical Standard Required (Draft SATS 1706:2016) Simple, practical and affordable solutions required.

7 SAFETY UV-A exposure is linked to skin maladies such as photo-aging and cancer It penetrates the atmosphere, clouds and glass. UV-B exposure is linked to skin maladies such as sun-burn and cancer It penetrates the atmosphere and clouds but not glass. UV-C (UVGI) exposure is NOT linked to severe skin maladies such as cancer but does cause severe eye irritation. It doesn’t penetrate the atmosphere glass or plastic.

8 EYE SAFETY The primary safety concern with UVGI is controlling eye exposure to prevent irritation (essentially arc-eyes) Safe exposure limits depend on the specific UV-C wavelength. Typically 6mJ/cm² per 8 hour working day for LPMV. Areas with lower typical occupancy durations can accommodate higher exposure levels. Areas such as passages and wards should demand different safety limits from each other

9 EYE SAFETY DRAFT

10 EYE SAFETY Avoid highly reflective surfaces in upper room (windows, chrome or aluminium flashing, etc) Surface reflection of UV is not the same as for visible light. (Polished aluminium is highly reflective in UV-C)

11 APPLICATION (UR-UVGI)
The application of Upper Room UVGI should form a component of a comprehensive IPC policy and should not be seen as a substitute thereof. Upper Room UVGI irradiates the upper room and relies on a vertical air exchange.

12 APPLICATION (UR-UVGI)
The dose received by any irradiated droplet nuclei is dependent on the exposure time. (W.s) the ratio between the volumes of the irradiated zone and the whole room therefore greatly affects the efficacy of the system

13 MEASUREMENT & METERS (METROLOGY)
Equipment Measurements performed using UV irradiance meters Performance evaluated to within 0.1 µW/cm² UV-C ( nm) Eye safety evaluated to within 0.01µW/cm² UV-B & UV-C ( nm) Procure facility-dedicated UV meters as components of new installation contracts Calibrate meters within system maintenance contracts

14 PLANNING AND PROCUREMENT
Pre-UV Questions / Gates Is TB risk in area HIGH? Is ventilation inadequate (WHO)? Can high risk activity not be relocated? Upgrade/Retrofit unfeasible? Then, and only then, consider UVGI

15 PLANNING AND PROCUREMENT
When planning/budgeting for installation, also plan for: Maintenance and monitoring Training Decommissioning and Disposal

16 PLANNING AND PROCUREMENT
Data required by designers: Room Occupancy level Ventilation & mode Room size and shape (incl height) Surfaces / obstructions

17 PLANNING AND PROCUREMENT
Data required for procurement: Specification of UV device Total maintained radiant flux mW (must be lifetime deprecated) SATS 1706 compliance (2016?) Equivalent clean air delivery rate Declaration of maximum 1m, 2m, and 3m deprecated µW/cm2 3 or more suppliers of basic consumables Minimum lamp change interval (≥ 1 year) Maintenance instructions Safety requirements

18 DESIGN Rational Design Equivalent Clean Air Delivery Rate
THREE DESIGN ROUTES AVAILABLE: Rational Design Performance Modelling Equivalent Clean Air Delivery Rate CADRe (L/s) Volumetric Flux Density mW/m³

19 DESIGN RATIONAL DESIGN Performance modelling requires the use of tools such as CAD and CFD Transmission reduction targets Device Radiometric data Ventilation and air movement data (HVAC or CFD) Agent susceptibility data (Z values)

20 DESIGN Design using device total maintained radiant flux (mW).
VOLUMETRIC FLUX DENSITY (UVc) Design using device total maintained radiant flux (mW). Independently measured in integrating sphere (eg TUKS) 𝑇𝑜𝑡𝑎𝑙 𝑀𝑎𝑖𝑛𝑡𝑎𝑖𝑛𝑒𝑑 𝑅𝑎𝑑𝑖𝑎𝑛𝑡 𝐹𝑙𝑢𝑥 𝑅𝑜𝑜𝑚 𝑉𝑜𝑙𝑢𝑚𝑒 ≥20𝑚𝑊/ 𝑚 3

21 DESIGN Accounts for levels of occupancy
EQUIVALENT CLEAN AIR DELIVERY RATE (CADRe) Accounts for levels of occupancy Bio-Aerosol decay tested in lab (NIOH) Equivalent Ventilation Rate → CADRe (L/s) Applies to expected occupancy levels + WHO high risk category High Risk ≥80 L/s per person Can be used for testing enclosed devices

22 DESIGN – Example A Room = 43.2m³ (4mx4m) Device A = 250 mW @R4500 ea.
Volumetric Distribution (20 mW/m³) Room = 43.2m³ (4mx4m) Device A = 250 ea. 43.2m³x20=864 mW 864/250 ≈ 3.5 devices → 4 devices @ R18 000 (View from top)

23 DESIGN – Example B Room = 43.2m³ (4mx4m) Device B = 500 mW @R6125 ea.
Volumetric Distribution (20 mW/m³) Room = 43.2m³ (4mx4m) Device B = 500 ea. 43.2m³x20=864 mW 864/500 ≈ 1.7 devices →2 devices @ R12 250 (View from top)

24 COST OF SYSTEM BY ROOM SIZE AND DEVICE OUTPUT (for illustration only)
DESIGN (PROCUREMENT) COST OF SYSTEM BY ROOM SIZE AND DEVICE OUTPUT (for illustration only) R10 /mW R12 /mW R18 /mW COST

25 DESIGN Device B = 250 L/s (CADRe) 2 devices x 250 = 500 L/s
WHO requires ≥ 80 L/s per person (Ventilation) Device B = 250 L/s (CADRe) 2 devices x 250 = 500 L/s ∴ 500/80 = 6.25 = 6 people maximum (View from top)

26 INSTALLATION Volumetric Distribution (20 mW/m³)
Volumetric Distribution (20 µW/cm²) Spot the mistake vs (View from top)

27 INSTALLATION Volumetric Distribution (20 mW/m³) vs (View from top)

28 INSTALLATION Volumetric Distribution (20 mW/m³) vs (View from top)

29 INSTALLATION ELECTRICAL SWITCHING AND OPERATION
UVGI devices must be permanently wired to the building electrical system Should be interlocked with paddle/ceiling fans The controls of UVGI devices or systems should only be accessible to authorised persons with the delegated authority and requisite training in safety and operation. Earth leakage required for devices that can be touched by room occupants (≈2.4m).

30 INSTALLATION CEILING FANS
Use when in doubt over vertical room air mixing (always?) Direction doesn't affect UVGI performance Blow down in high room volumes Blow up to avoid drafts in winter Interlock fan controllers with UV lights

31 INSTALLATION CEILING FANS (location) vs (View from top)

32 COMMISSIONING Prior to start up – CLEANING
Prior to acceptance testing – LAMP BURN-IN (Follow lamp manufacturer's recommendations as this can vary between brands and models)

33 COMMISSIONING (Effectiveness & Safety)
INITIAL PERFORMANCE VERIFICATION TESTING Verify EACH device’s performance independently Switch other devices off if necessary Measure 1 & 2m maximum irradiance values INITIAL SAFETY VERIFICATION TESTING Obtain agreed acceptance criteria for room Verify eye safety once performance tests are passed Verify with all devices turned on

34 MAINTENANCE & MONITORING
Lamps should be inspected and cleaned periodically Fixtures should be cleaned and inspected on the same schedule as the lamps 3 or 6 months depending on performance and environment All UV systems should be deactivated before workers enter the upper room zone. Maintenance staff require training in the following maintenance steps…

35 MAINTENANCE PROCEDURE
Turn off fixture and let lamps cool Open unit to manufacturer's specs Handle lamps with clean cotton gloves to prevent oil deposits & decreasing their efficiency Change lamps according to fixed schedule Change ballasts or ballasts of flickering lamps Clean lamps with alcohol dampened cloth (NOT WATER). Dry lamps with soft cotton cloth (lint free) Close fixtures Turn on the system and verify lamp operation (USE PPE) Record inspection, cleaning and replacement in maintenance logbook

36 MONITORING: Performance
Upper Room UVGI Measurements: Repeat 1m and 2m maximum irradiance measurements: Compare readings to previous values and declared maintained radiant flux. Take corrective action if required Log results and activities

37 MONITORING: Records

38 DECOMMISSIONING Lamps containing mercury vapour are considered as hazardous waste. Appropriate PPE should be worn where there is a risk of breaking lamps during disposal. gloves safety glasses and respiratory protection

39 Thanks & Acknowledgements:
Dr T Singh (NIOH) Prof A Stoltz (UP) P De Jager (CSIR) M Poluta (CSIR) Prof Edward A. Nardell (Brigham and Women's’ Hospital) Dr Steve N. Rudnick (Harvard School of Public Health) Richard L. Vincent (Mount Sinai Medical Center) Dr Paul Jensen (US Centres for Disease Control) Prof FW Leuschner (University of Pretoria) DR Lindiwe Mvusi (NDoH) documents-paper-and-articles

40 IUVA Draft Guideline IUVA-G02A-2005 International Ultraviolet Association Guideline for Design and Installation of UVGI Air Disinfection Systems in New Building Construction Copyright 2005 International Ultraviolet Association Fundamental Factors Affecting Upper-Room Ultraviolet Germicidal Irradiation—Part II. Predicting Effectiveness World Health Organisation. WHO Policy on TB Infection Control in Health-Care Facilities, Congregate Settings and Households. Geneva, Switzerland; 2004. World Health Organisation. Infection Prevention and Control of Epidemic- and Pandemic-Prone Acute Respiratory Diseases in Health Care. Geneva, Switzerland, Switzerland; 2007. World Health Organisation. Natural Ventilation for Infection Control in Health-Care Settings. Geneva, Switzerland; Accessed April 30, 2013. Downes A, Blunt T. Researches on the effect of light upon bacteria and other organisms. Proc R Soc London. 1877;26: Accessed May 28, 2014. Gates FL. A study of the bactericidal action of ultra violet light: III. The absorption of ultra violet light by bacteria. J Gen Physiol. 1930;14: Riley R. Guidelines for the Application of Upper-Room Ultraviolet Germicidal Irradiation for Preventing Transmission of Airborne Contagion — Part I : Basic Principles Wells WF, Fair MG. Viability of B. coli exposed to ultra-violet radiation in air. Science (80- ). 1935;82: Riley RL, Permutt S. Room air disinfection by ultraviolet irradiation of upper air. Arch Environ Heal An Int J. 1971;22(2): Riley RL, Permutt S. Convection, air mixing, and ultraviolet air disinfection in rooms. Arch Environ Heal An Int Journal ;22: Riley RL, Permutt S, Kaufman JE. Room air disinfection by ultraviolet irradiation of upper air: further analysis of convective air exchange. Arch Environ Heal An Int J. 1971;23(2):35-39. Escombe AR, Moore DAJ, Gilman RH, et al. Upper-room ultraviolet light and negative air ionization to prevent tuberculosis transmission. Wilson P, ed. PLoS Med. 2009;6(3):e43. doi: /journal.pmed Nardell EA, Bucher SJ, Brickner PW, et al. Safety of upper-room ultraviolet germicidal air disinfection for room occupants: results from the Tuberculosis Ultraviolet Shelter Study. Public Health Rep. 2008;123(1): Nardell EA. Environmental control of tuberculosis. Med Clin North Am. 1993;77(6): Accessed June 9, 2014. NIOSH US Department of Health, Education and Welfare PHS. Criteria for a Recommended Standard Occupational Exposure to Ultraviolet Radiation.; doi:(HSM) CIE Technical Division 6. CIE 155: 2003 Ultraviolet Air Disinfection. Vienna, Austria; doi:ISBN

41 The International Commission on Non-Ionizing Radiation Protection
The International Commission on Non-Ionizing Radiation Protection. Guidelines on Limits of Exposure to Ultraviolet Radiation of Wavelengths between 180 Nm and 400 Nm (Incoherent Optical Radiation). Vol 87.; doi: / R.L. Riley, M K, G M. Ultraviolet susceptibility of BCG and virulent tubercle bacilli. Am Rev Respir Dis. 1976;113: Mundt E, Nielsen P V. Ventilation Effectiveness.; 2004. 19. SATS 1706: 2015 SOUTH AFRICAN TECHNICAL STANDARD UVGI Luminaires - Safety and performance requirements. Beggs CB, Noakes CJ, Sleigh P a., Fletcher L a., Kerr KG. Methodology for determining the susceptibility of airborne microorganisms to irradiation by an upper-room UVGI system. J Aerosol Sci. 2006;37(7): doi: /j.jaerosci Illuminating Engineering Society of North America (IESNA) Testing Procedures Committee. Standard File Format for Electronic Transfer of Photometric Data and Related Information (ANSI/IESNA LM-63-02). New York; 2002. F.W. Leuschner. UVGI MEASUREMENTS, INSTRUMENTATION & FACILITIES PLAN. Pretoria; 2014. Zhang J, Levin R, Angelo R, et al. A radiometry protocol for UVGI fixtures using a moving-mirror type gonioradiometer. J Occup Environ Hyg. 2012;9(3): doi: / Illuminating Engineering Society of North America (IESNA) Testing Procedures Committee. IES Guide for Lamp Seasoning (LM-54-91). New York; 1991. First MW, Banahan KF, Dumyahn TS. Performance of ultraviolet germicidal irradiation and luminaries in long-term service. Leukos. 2007;3: doi: /LEUKOS South African Bureau of Standards. SANS 50285 : 2010 SOUTH AFRICAN NATIONAL STANDARD Energy Efficiency of Electric Lamps for Household Use Measurement Methods.; 2010. Vorlander FJ, Raddin EH. The effect of operating cycles on flourescent lamp performance. Illum Eng Miller S.L., Hernandez M., Fennelly K, et al. Environmental Control for Tuberculosis: Basic Upper-Room Ultraviolet Germicidal Irradiation Guidelines for Healthcare Settings. Cincinnati, OH; Xu P, Peccia J, Fabian P, et al. Efficacy of ultraviolet germicidal irradiation of upper-room air in inactivating airborne bacterial spores and mycobacteria in full-scale studies. Atmos Environ. 2003;37(3): doi: /S (02) Ko G, First MW, Burge H a. Influence of relative humidity on particle size and UV sensitivity of Serratia marcescens and Mycobacterium bovis BCG aerosols. Tuber Lung Dis. 2000;80(4-5): doi: /tuld Miller S, Hernandez M, Fennelly K. Efficacy of ultraviolet irradiation in controlling the spread of tuberculosis. Atlanta Centers Dis … Accessed August 15, 2014.

42 Mphahlele M, Dharmadhikari AS, Jensen PA, et al
Mphahlele M, Dharmadhikari AS, Jensen PA, et al. Institutional Tuberculosis Transmission: Controlled Trial of Upper Room Ultraviolet Air Disinfection - A Basis for New dosing Guidelines. Am J Respir Crit Care Med. 2015: doi: /rccm OC. Noakes CJ, Beggs CB, Sleigh PA, Kerr KG. Effect of Room Mixing and Ventilation Strategy on the Performance of Upper Room Ultraviolet Germicidal Irradiation Systems. In: Proceedings of ASHRAE IAQ ; 2004:1-13. First M, Rudnick SN, Banahan KF, Vincent RL, Brickner PW. Fundamental factors affecting upper-room ultraviolet germicidal irradiation - part I. Experimental. J Occup Environ Hyg. 2007;4(5): doi: / ASHRAE. ASHRAE ; Thermal environmental conditions for human occupancy. Am Soc Heating, Refrig Air Cond Coker I, Nardell E, Fourie B. Guidelines for the Utilisation of Ultraviolet Germicidal Irradiation (UVGI) Technology in Controlling the Transmission of Tuberculosis in Health Care Facilities in South.; Accessed June 30, 2014. Kowalski W, Bahnfleth W. Proposed standards and guidelines for UVGI air disinfection. IUVA News. 2004;6(1): Rudnick SN, First MW. Fundamental factors affecting upper-room ultraviolet germicidal irradiation - part II. Predicting effectiveness. J Occup Environ Hyg. 2007;4(5): doi: /

43 Tobias van Reenen (tvreenen@csir.co.za)


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