ASHRAE on UVGI 2014 - c.ymcdn.com · Establishing Performance Standards and Testing for UVC. Using...
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Transcript of ASHRAE on UVGI 2014 - c.ymcdn.com · Establishing Performance Standards and Testing for UVC. Using...
The agenda
• ASHRAE : UVGI
1) SCIENCE OF UVC
2) IN DUCT AIR PURIFICATION
3) UPPER ROOM UVGI
4) EVAPORATOR COIL UVGI
5) HOSPITAL ACQUIRED INFECTIONS AND UVGI
Using UV - Air Purification ASHRAE Past, Present & Future2005: ASHRAE Technical Group 2.UVAS
2008: First Handbook chapter: UVC Lamp Systems: Chapter 16
2011 Handbook: HVAC Applications : Chapter 60: Ultraviolet Air and Surface Treatment Applications
2012 Handbook: ”HVAC Systems and Equipment: Chapter 17: Ultraviolet Lamp Systems which includes information from Research Project 1509-RP on the degradation of Typical HVAC Materials, Filters and Components Irradiated by UVC Energy.
2012: ASHRAE IAQ Guide: Best Practices recognizes the use of UVC Lamp Systems
Moving Forward:More Research Projects Expanding the knowledge base of UVCEstablishing Performance Standards and Testing for UVC
Using UV - Air Purification
Perpendicular Placement Parallel Placement
2 year double blind office study - McGill University and Lancet Medical Journal 2000
Using UVGI for Air Sterilization - EPA/Homeland Security 2008
Report on Assessment of Germicidal UV Lights in the Sputum Induction Room at the Montreal Chest Institute. McGill University 2000
Effect of Ultraviolet germicidal irradiation in the heating, ventilation and air conditioning system on ventilator associated pneumonia in a neonatal intensive care unit” Journal of
Perinatology. 2011
Home Isolation & use of portable HEPA/UVGI units – Toronto Public Health. Nov. 2012
UVC: Florida Hospital Puts HVAC Under a New Light”, Engineered Systems Feb. 2003
Guidelines on the Design and Operation of HVAC Systems in Disease Isolation Areas, TG 252. Nov. 2000 - US ARMY
Advanced HVAC Systems for Improving Indoor Environmental Quality and Energy Performance of California K-12 School. Applications Guide for Off the Shelf Equipment for
UVC Use. May 2006
CDC: Guideline for Disinfection and Sterilization in Healthcare Facilities, 2008
Life-Cycle Cost Simulation of In-Duct Ultraviolet Germicidal Irradiation Systems. 2011
The Importance of Bioaerosols in Hospital Infections and the Potential for Control using Germicidal Ultraviolet Irradiation. 2004
Using UVGI to counter contaminant dispersion. IFHE Digest 2011
The Application of Ultraviolet Germicidal Irradiation to Control Transmission of Airborne
Sun’s UV rays
How UV Works
UV Causes MicroorganismTo Stop Functioning Properly
More Importantly DestroyingBio-Contaminant’s Greatest WeaponThe Ability to Reproduce
Micro-organism Susceptibility to UVC
Aspergillus Niger 330,000
%Disinfection
UVGI Lamps
- Mercury, Xenon, Argon Gas Mixture- Quartz to allow transmission of UVC- Doped to emit 254nm specifically- As gas mixture uses itself up, replacement
of lamp is necessary- 1 year or 2 year lamps
Lamp Cooling and Lamp Fouling
The two greatest factors that influence the efficiency of a UV Lamp are:
A) Lamp Cooling
B) Lamp Fouling
Using UV In Duct – Air Purification
- Return or supply duct - Treat entire wing/multiple rooms with a single install- Airborne UV Disinfection to protect occupants and vaccinate the building.
Using UV In Duct – Air Purification
Variables for Sizing for Air Sterilization
• Dimension of the installation point in duct: W x H
• Volume of air passing through duct
Upper Air UV
Upper Air UV
Typically installed on a wall above seven feet, the louvers reflect the UV to the upper air region of the space.
As air currents bring bacteria to the upper air of the space, they are irradiated with UVC
One of the first type UV systems, they faded in use, and now have made a resurgence because of Multi-drug resistant organisms and Hospital Acquired Infections.
Most cases, more than one unit is needed in a room to adequately cover the space.
Typically used in TB applications
Sizing: Room dimensions and contaminant to be irradiated
Evaporator Coil UV
UVGI for Coil Cleaning ‐ Benefits Include: Destroys mold and other microbial growth (bio-film) on the
evaporator coil as well as biological odors
Potential energy savings (average 5-15%) from a consistent, clean coil
Eliminates coil maintenance as pressure washing can damage the coil fins and impact debris in the center of the coil
Eliminates need for Drain Pan Tabs
Can reduce static pressure (w.g.) through coil
Improve cooling transfer efficiency
Potentially raise cooling tower water temperature
Potentially lengthen the lifespan of the coil by eliminating corrosive Biofilm
University tested & published results in The Lancet Medical Journal- 99% microbial and endotoxin reduction in AHU - 40% reduction in respiratory illness- 20% reduction in all worker symptoms – reducing abenteeism
**The lines in the agar are the impressions made from pressing the plates against the fins of the coil
**After 10 hours of UV exposure
(Incubation 4 days)Before UV
(Incubation 4 days)
The results are always the same.
Using UV Indoors– Object Purification
Both Sides will keep a coil clean ‐ Downstream vs. UpstreamWe prefer Upstream as a first choice.
Using UV – Coil Sizing
Sizing Performance ‐ Upstream sizing for Coil 140”Wx120”H
UV – Hospital Acquired infections
• Infection Prevention: The Threat of Dirty Air
