AIR BORNE INFECTIONAIR BORNE INFECTIONCurrent Situation ,Current Situation ,

Opportunities for ImprovementOpportunities for Improvement&&

Possible Mechanism for Possible Mechanism for Implementation Implementation

Dr R ChandrashekharDr R ChandrashekharChief Architect DteGHS Chief Architect DteGHS

Ministry of Health & F W Govt. of IndiaMinistry of Health & F W Govt. of India

Ventilation - DesignVentilation - Design

ConsiderationsConsiderations– Site design – building location, layout, orientation, landscaping…– building location, layout, orientation, landscaping…– Building design – type, function, form, envelope, ventilation – type, function, form, envelope, ventilation

strategy…strategy…– Vent opening design – position, types, size…– position, types, size…

PrinciplesPrinciples– Select desired airflow patternSelect desired airflow pattern– Identify the driving forcesIdentify the driving forces– Size and locate the openingsSize and locate the openings

Ventilation - MethodsVentilation - Methods

NaturalNatural

Mechanical (with fans)Mechanical (with fans)

HybridHybrid

ZONING / LOCATIONZONING / LOCATIONSeparation of Curative & Preventive AreaAppropriate traffic flow (e.g., no “dirty” movement through “clean” areas)Location of sinks and dispensers for hand washingConvenient location of soiled utility areas Isolation rooms with anterooms as appropriateLocation of adequate storage and supply areasProperly engineered areas for linen services and solid waste managementAir-handling systems engineered for optimal performance, easy maintenance, and repair

Use of Use of EEnvironmental controlsnvironmental controls to prevent the to prevent the spread and reduce the concentration of spread and reduce the concentration of infectious droplet nuclei in ambient air.infectious droplet nuclei in ambient air.

Primary environmental controlsPrimary environmental controls consist of consist of controlling the source of infection by using local controlling the source of infection by using local exhaust ventilation (e.g., hoods, tents, or exhaust ventilation (e.g., hoods, tents, or booths) and diluting and removing contaminated booths) and diluting and removing contaminated air by using general ventilation air by using general ventilation

Secondary environmental controlsSecondary environmental controls consist of consist of controlling the airflow to prevent contamination controlling the airflow to prevent contamination of air in areas adjacent to the source (AII rooms) of air in areas adjacent to the source (AII rooms) and cleaning the air by using high efficiency and cleaning the air by using high efficiency particulate air particulate air (HEPA), filtration, or UVGI(HEPA), filtration, or UVGI. .

Improperly maintained HVAC systems may cause Improperly maintained HVAC systems may cause symptoms associated with symptoms associated with Sick Building Sick Building SyndromeSyndrome (SBS).(SBS).SBS symptoms that may be attributed to SBS symptoms that may be attributed to moisturemoisture with the HVAC systemswith the HVAC systems""HumidificationHumidification systems with poor systems with poor condition/maintenance were associated with condition/maintenance were associated with significantly increased upper respiratory symptoms, significantly increased upper respiratory symptoms, eye symptoms, fatigue/difficulty concentrating, and eye symptoms, fatigue/difficulty concentrating, and skin symptomsskin symptomsLess frequent cleaning of cooling coils and Less frequent cleaning of cooling coils and drain pansdrain pans was associated with significantly was associated with significantly increased eye symptoms and headacheincreased eye symptoms and headacheSymptoms may be due to microbial exposures Symptoms may be due to microbial exposures from poorly maintained ventilation systemsfrom poorly maintained ventilation systems and and to greater levels of vehicular pollutants at air to greater levels of vehicular pollutants at air intakes nearer the ground levelintakes nearer the ground level

1 - Supply duct2 - Fan compartment3 - Vibration isolators4 - Heating and/or cooling coil5 - Filter compartment6 - Return and fresh air duct

Air Handling Unit

Moisture-related HVAC components such as Moisture-related HVAC components such as cooling coils and humidification systemscooling coils and humidification systems, , when poorly maintained, may be sources of when poorly maintained, may be sources of contaminantscontaminants that cause adverse health effects that cause adverse health effects in occupants, even if we cannot yet identify or in occupants, even if we cannot yet identify or measure the causal exposuresmeasure the causal exposures

If you have dirty or If you have dirty or inefficient cooling coilsinefficient cooling coils, your , your HVAC is likely a reservoir for microorganisms. HVAC is likely a reservoir for microorganisms. These microorganisms can cause symptoms These microorganisms can cause symptoms associated with SBS, in hospitals these associated with SBS, in hospitals these pathogens can promote pathogens can promote Hospital Acquired Hospital Acquired Infections (HAI).Infections (HAI).

SOLUTIONSOLUTION

The need for The need for Ultraviolet Germicidal Ultraviolet Germicidal Irradiation (UVGI)Irradiation (UVGI) in all air conditioned in all air conditioned buildings buildings UVGIUVGI deactivates bacteria, fungi and deactivates bacteria, fungi and viruses on surfaces as well as in the air. viruses on surfaces as well as in the air. Importantly, this protection is constant. Importantly, this protection is constant. Unlike one time cleanings the germicidal Unlike one time cleanings the germicidal irradiation of cooling coils continues 24 irradiation of cooling coils continues 24 hours a day hours a day

A supplemental A supplemental Portable anteroom High-Efficiency Portable anteroom High-Efficiency Particulate Air (PAS- HEPA)Particulate Air (PAS- HEPA) filter unit placed outside filter unit placed outside operating room suites may prevent secondary operating room suites may prevent secondary transmission of airborne microorganisms like transmission of airborne microorganisms like Mycobacterium tuberculosis (M. tuberculosis).Mycobacterium tuberculosis (M. tuberculosis).study reinforces use of portable anteroom HEPA filtrationstudy reinforces use of portable anteroom HEPA filtrationFilters are great for trapping microorganisms, Filters are great for trapping microorganisms, but they do but they do not 'killnot 'kill'. Eventually filters can become colonized and act '. Eventually filters can become colonized and act as a breeding ground for pathogens. Thinking that you as a breeding ground for pathogens. Thinking that you have 100% protection because you have have 100% protection because you have HEPAHEPA filtration filtration is a false sense of security.is a false sense of security.It is suggested to have a It is suggested to have a balance between UV and balance between UV and filtrationfiltration to provide a better strategy for reducing to provide a better strategy for reducing environmental pathogens in critical care areas of your environmental pathogens in critical care areas of your hospital.hospital.Ionic air purifiersIonic air purifiers have undeniable appeal, but there's a have undeniable appeal, but there's a problem: They don't really improve air qualityproblem: They don't really improve air quality

IAQIAQ

Particulates

Microbial

Gases

ParticulatesParticulates

Dust, dander, pollen, organic clumpsDust, dander, pollen, organic clumpsUsually handled by air filtration.Usually handled by air filtration.Filters must be maintained to be Filters must be maintained to be affective.affective.

MicrobialMicrobial

•Single Cell OrganismSingle Cell Organism•Self contained and can reproduce without a hostSelf contained and can reproduce without a host•E.g., MRSA, E.g., MRSA, E. Coli, Staph, Strep…..

Bacteria

Viruses

Mold Spores

•Minimal structure of genetic material and proteinMinimal structure of genetic material and protein•Can only be seen with an electron microscopeCan only be seen with an electron microscope•E.g., Norwalk, SARS, Avian Flu….E.g., Norwalk, SARS, Avian Flu….

•Airborne Single Cell OrganismAirborne Single Cell Organism•Grows into mold as soon as conditions permitGrows into mold as soon as conditions permit•Causes allergic reactions, asthma episodes, Causes allergic reactions, asthma episodes, irritations, infections, sinus congestion irritations, infections, sinus congestion problems….problems….

GasesGases•VOC’s (Volatile Organic Compound)VOC’s (Volatile Organic Compound) are found are found in smoke, adhesives, carpets, cleaning agents, in smoke, adhesives, carpets, cleaning agents, nail polish, paint, new construction, pressed nail polish, paint, new construction, pressed wood products…wood products…•Can cause eye, nose, and throat irritation, Can cause eye, nose, and throat irritation, headaches, loss of coordination, nausea…headaches, loss of coordination, nausea…

VOC’s

Odors•Caused by odorant molecules dissolved in the Caused by odorant molecules dissolved in the air.air.•E.g., pet odors, perfumes, food odors…E.g., pet odors, perfumes, food odors…

Current IAQ TechnologiesCurrent IAQ Technologies

ULTRA VIOLET LIGHT For Microbial

Inverse Square Law

UV100% POWER

25% POWER

6.25% POWER

1.56% POWER

1”

2”

4”

8”

UV Treated Heat Exchanger

On Surface

Inside Heat Exchanger

PHOTO HYDRO IONIZATION (PHI )PHOTO HYDRO IONIZATION (PHI )

Hydrogen based oxidizers are created by Hydrogen based oxidizers are created by exposing activated oxygen molecules to a exposing activated oxygen molecules to a hydrated catalyst containing four unique metals hydrated catalyst containing four unique metals and 300 nm UV lightand 300 nm UV light (Photon Energy). (Photon Energy).

These Friendly Oxidizers are….These Friendly Oxidizers are….

– Hydro-peroxidesHydro-peroxides– HydroxidesHydroxides– Super Oxide IonsSuper Oxide Ions– Ozonide IonsOzonide Ions

HVAC PHI

HVAC PHI

The System is designed to provide enough The System is designed to provide enough UVC exposure (dose) to destroy UVC exposure (dose) to destroy aspergillus. UV technology disinfects aspergillus. UV technology disinfects HVAC surfaces and then keeps those HVAC surfaces and then keeps those areas clean by continuously radiating the areas clean by continuously radiating the reservoirs where microorganisms can reservoirs where microorganisms can thrive.thrive.

This Systems combine This Systems combine filtrationfiltration and the and the germicidal effect of germicidal effect of UVCUVC. Rather than just . Rather than just trapping aspergillus spores trapping aspergillus spores

What is PHI CellWhat is PHI Cell

•Friendly Oxidizers are blown into the conditioned space

•Microbes and gases are destroyed on contact.

•Oxidizers break down into oxygen and water vapor

Kills airborne and surface pollutants

This is an integrated system of This is an integrated system of components engineered for components engineered for Indoor Air Indoor Air Quality (IAQ),Quality (IAQ), air purification, energy air purification, energy savings and bio-defense. The major savings and bio-defense. The major components of this System are components of this System are ultra violet germicidal irradiation, , filtration, , reflective materials and monitoring reflective materials and monitoring hardware.hardware.

This is This is flexibleflexible and can be installed in and can be installed in any new or existing HVAC system.any new or existing HVAC system.

HEPA - MDHEPA - MDTMTM

High Efficiency Particulate Arrestance - High Efficiency Particulate Arrestance - Microbial DestructionMicrobial Destruction

HEPA - MDTM REACTOR

Exposition to a non thermal plasma

Capture by a electrical media

1

Reactor with

4 modules

Molecular filtration3

2

2

12

3

4

Molecular Trapping4

HEPA - MD Technology

Destruction of airborne microorganisms by exposure to strong electric fields and to oxidative species in unique non-thermal plasma chambers

Charged materials exiting stage 1 are captured by an electrically active media where organic materials are continuously exposed to the plasma ions

Oxidant chemical species are removed by a catalytic monolith (notably ozone and NOx)

2. Biological decontamination and High Efficiency Particulate

Arrestance

1. Microbial Destruction

3. Catalytic Conversion

4. Molecular Trapping

Organic and mineral volatile molecular pollutants are adsorbed onto an activated carbon medium

Compounds and Odors Effectively RemovedCompounds and Odors Effectively Removed

VOC removedVOC removed ODORS removedODORS removed

Product RangeProduct Range

Mobile Air-decontamination unit

Mobile Protective Environment

Ceiling Diffuser Systems for air decontaminationin high infectious risk zones

Ceiling Air-decontamination unit

– Creating comfort conditions in Creating comfort conditions in “General Areas” in place of “General Areas” in place of normal air-conditioning by low-normal air-conditioning by low-energy techniquesenergy techniques

– Earth Tunnel cooling systems Earth Tunnel cooling systems for non air-conditioned spacesfor non air-conditioned spaces

– Use of flash-misting and other Use of flash-misting and other evaporative techniques evaporative techniques including indirect systemsincluding indirect systems

HVAC and Climate Control

Improve Indoor air quality with well designed ventilation system and air filters to prevent nosocomial infection.

– VAV (Variable Air Volume) VAV (Variable Air Volume) systems for efficiency in systems for efficiency in unbalanced occupancy unbalanced occupancy conditions coupled with VFDs in conditions coupled with VFDs in Air Handling UnitsAir Handling Units

– Enthalpy ( Total Heat) Control in Enthalpy ( Total Heat) Control in non-medical areasnon-medical areas

HVAC and Climate Control (Contd.)

VAV System

Enthalpy controlEnthalpy control is a control which checks to see if is a control which checks to see if both the temperature (sensible heat) and the humidity both the temperature (sensible heat) and the humidity (latent heat) are low enough to be used for cooling. (latent heat) are low enough to be used for cooling. This combination provides for the greatest comfort at This combination provides for the greatest comfort at the least cost.the least cost.

If the indoor thermostat calls for cooling and the If the indoor thermostat calls for cooling and the outside air outside air enthalpy (total heat)enthalpy (total heat) is low enough then the is low enough then the economizer brings in this cooler and less humid air economizer brings in this cooler and less humid air and uses it for cooling instead of operating the and uses it for cooling instead of operating the compressor. Using the outside air for cooling is less compressor. Using the outside air for cooling is less expensive than operating the compressor to provide expensive than operating the compressor to provide cooling.cooling.

Enthalpy control is located in the outdoor air air-Enthalpy control is located in the outdoor air air-stream and is a relatively sensitive control, it is not stream and is a relatively sensitive control, it is not uncommon to have to replace it every few years uncommon to have to replace it every few years depending upon the location of the equipment and the depending upon the location of the equipment and the weather extremes in the area.weather extremes in the area.

STUDIES & FINDINGSSTUDIES & FINDINGS

For the effectiveness of UVGI, the best ventilation rates For the effectiveness of UVGI, the best ventilation rates seem to fall in the range of seem to fall in the range of 10-12 ACH for winter10-12 ACH for winter (no (no baseboard heating) and at baseboard heating) and at 6ACH for summer6ACH for summer with the with the UVGI locationUVGI locationUVGI does result in the killing of a significant percentage UVGI does result in the killing of a significant percentage of the viable particles in the room.of the viable particles in the room.Changing the location of the UV lamp and increasing its Changing the location of the UV lamp and increasing its intensity result in a higher percentage of particles being intensity result in a higher percentage of particles being killed. However, further increases in UV intensity show killed. However, further increases in UV intensity show diminishing returns. diminishing returns. The addition of baseboard heating results in better kill The addition of baseboard heating results in better kill UVGI rates irrespective of ACH.UVGI rates irrespective of ACH.Baseboard heating should therefore be used in winter Baseboard heating should therefore be used in winter cases, especially at low ACH.cases, especially at low ACH.

Assessing the Efficacy of Ultraviolet Germicidal IrradiationAssessing the Efficacy of Ultraviolet Germicidal Irradiationand Ventilation in Removing Mycobacterium Tuberculosisand Ventilation in Removing Mycobacterium Tuberculosis

High level exhausts are generally better High level exhausts are generally better than low level exhausts in terms of vented than low level exhausts in terms of vented percentage for the particle release points percentage for the particle release points considered in the study, particularly at low considered in the study, particularly at low to medium ACH. This trend is not present to medium ACH. This trend is not present at the higher values of ACH. However, at the higher values of ACH. However, note that patient rooms display better air note that patient rooms display better air conditions for low exhausts at low to conditions for low exhausts at low to medium ACH, medium ACH,

Opening windows and doors provides Opening windows and doors provides maximum natural ventilation and this maximum natural ventilation and this lowers the risk of lowers the risk of airborneairborne contagion contagion

opening windows and doors provides opening windows and doors provides ventilation more than double that of ventilation more than double that of mechanically ventilated negative-pressure mechanically ventilated negative-pressure rooms and 18 times that of rooms with rooms and 18 times that of rooms with windows and doors closed.windows and doors closed.

Even at the lowest of wind speeds, natural Even at the lowest of wind speeds, natural ventilation exceeded mechanical ventilation. ventilation exceeded mechanical ventilation. Facilities built more than 50 years ago, Facilities built more than 50 years ago, characterized by characterized by large windows and high large windows and high ceilings,ceilings, had greater ventilation than modern had greater ventilation than modern naturally ventilated rooms.naturally ventilated rooms.

Opening windows and doors maximizes natural Opening windows and doors maximizes natural ventilation and that the risk of ventilation and that the risk of airborneairborne contagion contagion is lower than with mechanical ventilation is lower than with mechanical ventilation systems. Old-fashioned clinical areas with high systems. Old-fashioned clinical areas with high ceilings and large windows provided the greatest ceilings and large windows provided the greatest protection.protection.

A R T CENTRE At Dr R M L HOSPITAL DELHI

600x300(1200)

600x300150x300 (500)

450x300275x300 (500)

275x300175x300 (500)

OUT DOOR 3.0TR

AC MCB BOXFOR 1.5 TR

AC MCB BOXFOR 3.0 TR

AC MCB BOXFOR 3.0 TR

EXHAUST FAN(02SETS) SUPPLY FAN

(01 SET)

SUPPLY FAN (01 SET)

EXHAUST FAN(02 SETS)

1.5 TR1.5 TR1.5 TR1.5 TR

1.5 TR

850 CMH

850 CMH

850 CMH

2000 CMH 2000 CMH 2000 CMH 2000 CMH

LOCAL CONTROL PANEL

6000 CMH

1000 CMH

6500 CMH1500 CMH

1500 CMH 1500 CMH

AIR WASHER UNIT 7500 CMH(EACH) 2NOS

OUT DOOR 3.0 TR

OUT DOOR 1.5 TR

SUPPLY FAN (01 SET)

SUPPLY FAN (01 SET)

A R T CENTRE AT Dr R M L HOSPITAL DELHI

WAITING AREA

CONSULTANT ROOM

CUT OUT IN DOOR FOR AIR OUTLET

WAITING AREA

WAITING AREA ( EXHAUST AIR )

DIVIDER BETWEEN WAITING AREAS

+VE

+VE

- VE

- VE

WAITING AREA WITH NATURAL LIGHT & VENTILATION

Natural Light

TYPICAL WARD LAYOUT

TOILET(M)

TOILET(F)

BALCONY

D.U.

C.U.

STORE

ISOLATIONROOM

TOILET

ISOLATION

TREATMENTROOM

TOILET

NURSERESTRM.

DAY ROOM

NURSES' STN.

NURSES' STN.LIGHTSHAFT

LIGHTSHAFT

LIGHTSHAFT

G.T

L.T

TOILET(M)

TOILET(F)

VISITORWAITING

TEACHING

DOC.DUTY

DOC.TOILET

PANTRY

TOI.

TYPICAL WARD LAYOUT

D.U.

C.U.

STORE

ISOLATION

TREATMENTROOM

TOILET

NURSERESTRM.

NURSES' STN.

NURSES' STN.LIGHTSHAFT

LIGHTSHAFT

TOILET(M)

TOILET(F)

TEACHING

DOC.DUTY

DOC.TOILET

PANTRY

TOI.

TYPICAL WARD LAYOUT

TOILET(M)

TOILET(F)

BALCONYISOLATIONROOM

TOILET

NURSERESTRM.

DAY ROOM

NURSES' STN.

NURSES' STN.LIGHTSHAFT

LIGHTSHAFT

G.T

L.T

VISITORWAITING

TOI.

TYPICAL DETAIL OF ONE CUBICLE IN WARD

DETAIL AT "A"

SCALE-1:100

WARD DESIGN WITH EVIDENCE BASED

Antibiotics are not the cure for superbugs, cleanliness is - and the hospitals simply aren't clean enough in India .

Accountability is needed, not money,

Run a hospital like a fast food joint. "Clean as you go" and it is all staff's responsibility to clean up, not delegated to the lowest bidder

FOR ANY QUERY

E - Mail

cdb@nb.nic.in