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Why do we need?
Negative Pressure Isolation Room❑ Covid-19
• An infectious disease caused by the SARS-CoV-2 virus
• The virus can spread from an infected person’s mouth or nose in small liquid particles when they cough, sneeze, speak, sing or breathe
FIGURE Schematic of negative pressure room
• Since the air rushes into the room when a door is opened, the germs all stay inside the room with the patient
• When the air leaves the room, it must go thorough a HEPA filter
before recirculating throughout the hospital
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HEPA filter
Negative Pressure Isolation Room❑ HEPA filter
• An acronym for “high efficiency particulate air”
• HEPA filter is a type of
pleated mechanical air filter
• This type of air filter can
theoretically remove at least 99.97% of dust, pollen, mold, bacteria, and any airborne particles with a size of 0.3 microns (μm)
FIGURE HEPA filter
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Configuration of NPIR
Negative Pressure Isolation Room❑ Negative pressure isolation area
• An area with lower negative pressure than non-negative
pressure areas including wards, annexes, and essential support facilities for treating patients with high-risk infectious diseases
❑ Non-negative pressure zone
• An area adjacent to the negative pressure zone in which a
nursing station is installed to prepare for treatment of patients with infectious diseases and to observe the patient’s condition
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Configuration of NPIR
Negative Pressure Isolation RoomFIGURE Negative pressure ward and anteroom
❑ Negative pressure isolation ward
• A ward in which an infectious disease patient is admitted in the inpatient treatment area.
• A continuous negative pressure is maintained inside the ward, and shower facilities and toilets that can be accessed directly from the ward
❑ Anteroom
• A space for preparing for basic infection prevention, prevent air infection and plays a role in maintaining the negative pressure
https://www.priceindustries.com
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Facility standards
Negative Pressure Isolation Room❑ Facility standards
• The negative pressure isolation room should be physically separated from the general area of the hospital and divided into a negative and a non-negative pressure area
• In the negative pressure isolation area, all corridors, changing rooms, anterooms, wards and toilets, waste treatment room, equipment storage room, etc. are arranged and the nursing station is designed to facilitate observation
FIGURE Negative pressure tent
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Structure of NPIR
Negative Pressure Isolation RoomFIGURE Negative Pressure Isolation Room Structure
https://www.gyeongnam.go.kr/
❑ Structure of NPIR
• There are two main passages to and from the negative pressure room which is divided into medical and patient use
• There are also anteroom at the entrance to the hallway where patients enter.
• There are two automatic door between hallway to anteroom and anteroom to the ward
• These two doors never open at the same time in order to prevent the
possible airborne infection
• The pressure difference between each room must be maintained at least 2.5 Pa
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Structure of NPIR
Negative Pressure Isolation Room❑ Negative Pressure Anteroom
• Pressure drops hall, anteroom, ward, bathroom respectively
• Air control is relatively easy
• If the patient in the ward is infirm, this may cause additional infection by the inflow of external pollutants
FIGURE Negative Pressure Anteroom
❑ Structure of NPIR
• Most commonly used structure of the NPIR is the Hall-Anteroom-Ward-Bathroom
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Structure of NPIR
Negative Pressure Isolation RoomFIGURE Positive Pressure Anteroom
❑ Positive Pressure Anteroom
• Structure with the positive pressure anteroom
• It has advantage of protecting the patient in the ward from the external pollutants while the door is closed
• The defect is that the medical staff from the ward to the anteroom may draw the air from the ward to outside
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Automatic control
Negative Pressure Isolation Room❑ Automatic control of negative pressure isolation rooms
• An air conditioning control system that controls the negative pressure isolation room to always maintain the negative
pressure ,proper temperature and humidity.
https://www.johnsoncontrols.com/
FIGURE 3D image of a NPIR with HVAC Controls pop outs
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NPIR of Korea
Negative Pressure Isolation Room❑ SARS (2003)
• After SARS, we have been building negative pressure
isolation rooms since 2006, starting with the National medical Center
❑ NPIR of Korea have been developed with major epidemics
https://www.medpagetoday.com/
FIGURE SARS virus
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NPIR of Korea
Negative Pressure Isolation Roomhttp://ready.nj.gov/
❑ Pandemic influenza (2009)
• After the 2009 pandemic influenza in Korea, the Korea
centers for Disease Control and Prevention (KCDC) revised the ‘Act on the Prevention and Management of Infectious Diseases’
• ‘Regulations on the Operation of National Hospitalized Treatment Beds’ in 2010 established a legal basis for nationally designated inpatient treatment beds
FIGURE Pandemic influenza virus
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NPIR of Korea
Negative Pressure Isolation Room❑ MERS (2015)
• When MERS broke out in 2015, group infections were carried out through domestic medical institutions, further
strengthening facility standards and expanding the scale.
• In particular, the related laws have been strengthened to
ensure that general hospitals with more than 300 beds have negative pressure isolation rooms.
https://dongascience.com/
FIGURE MERS virus
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NPIR of Korea
Negative Pressure Isolation Roomhttps://easl.eu/
❑ Covid-19 (2019)
• As of 2011, the nationally designated inpatient
treatment(isolation) beds were 360 beds (69 negative
pressure beds, 291 general beds) in 10 hospitals across the country
• Currently, the scale has been expanded to 566 beds (194 negative pressure beds, 372 general beds) in 29 hospitals across the country
FIGURE Covid-19 virus
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Law about the NPIR
Negative Pressure Isolation Room❑ There are related regulations in the Enforcement Regulations of the Infectious Disease Prevention and Control Act Article 31, Paragraph1, Item 1
❑ Installation Duty
• Infectious disease control institution with 300 or more beds : Install at least one negative pressure room that meets the criteria
• Infectious disease control institution with less than 300 beds : At least one isolated treatment room or isolated ward should be installed
• If a negative pressure room is not installed, a corrective order may be issued under the medical Act
• Also, if a tertiary general hospital does not install a negative pressure room, the designation of a tertiary general hospital will be cancelled
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Law about the NPIR
Negative Pressure Isolation Room❑ Installation Criteria
• Negative pressure bed : Secure an area of 15m2 or more
• Anteroom : Install in a place that can physically separate the negative pressure area with the negative pressure bed and the non-negative pressure area
• Toilet : install in a space with a negative pressure bed
• Supply/discharge facility for negative pressure : Install it separately from other supply/discharge facilities, and install a HEPA filter
• Negative pressure backflow prevention facility : to be installed on the pipe in the space where the negative pressure bed is located
• Negative pressure drainage treatment and collection tank : install separately from other drainage treatment and
collection facilities
Solar Power
Generation System
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Solar Power Generation System
Solar Power Generation System• Very low running cost
• No mechanical vibration, no noise
• Life of solar cell is more than 20 yrs
• Infinite energy source
• No pollutant generation Advantages
• High initial cost
• Variation of energy generation since cloudy or rainy weather
• Need large area
• Low energy density Disadvantages
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Classification
Solar Power Generation System❑ Photovoltaic system
• Photo + Volta
Converts the energy of light directly into electricity by the photovoltaic effect
FIGURE Solar power tower at Crescent Dunes Solar Energy Project
FIGURE Concentrator photovoltaics modules on dual axis solar tracker in Golmud, China
❑ Solar heat system
(CSP: Concentrated Solar Power)
• Generation with solar heat, useful for power plant
• Use mirrors or lenses to concentrate a large area of sunlight onto a receiver
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Photovoltaic System
Solar Power Generation System❑ Component
• Solar photovoltaic array
• Change controller
• Battery bank
• Inverter
• Utility Meter
• Electric Grid
❑ Photovoltaics(PV) : Conversion of light into electricity using semiconducting materials
• A common single junction silicon solar cell can produce a
maximum open-circuit voltage of approximately 0.5 to 0.6 volts
FIGURE Diagram of the components of a Photovoltaic system
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Photovoltaic System
• The light’s energy called photons, falls onto a solar panel and creates an electric
current through a process called the photovoltaic effect.
• The electricity produced is in the form of direct current (DC), so it must first be converted from DC to AC using an inverter.
• This AC electricity from the inverter can then be used, or be sent on to
the electrical grid for use Solar Power Generation System
FIGURE Photovoltaic System
Solar Photovoltaic Systems in the UK (2021) | GreenMatch
❑ Process of Photovoltaic generation
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Solar Power Generation System
Photovoltaic System
❑ Standalone system
Automatic solar system that produces electrical power to charge banks of batteries during the day for use at night when the suns energy is
unavailable.
❑ Grid connection system
The photovoltaic panels or array are connected to the utility grid through a power inverter unit allowing them to operate in parallel with the electric utility grid
Figure Configuration of standalone system
Figure Configuration of greed connection system
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Photovoltaic System – Photovoltaic cells
❑ Photovoltaic effect: Process by which PV cell converts the absorbed sunlight energy into electricity
Solar Power Generation System
FIGURE Schematic diagram of a conventional solar cell
1) When light of a suitable wavelength strike the cells, energy is transferred to an atom of the semiconducting material in the p-n junction.
2) Specifically, the energy is transferred to the electrons in the material. This causes the electrons to jump to a higher energy state known as the conduction band.
3) This leaves behind a "hole" in the
valence band that the electron jumped up from.
Mlinar, Vladan. "Engineered nanomaterials for solar energy conversion." Nanotechnology 24.4 (2013): 042001.
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Solar Power Generation System
❑ Photovoltaic effect: Process by which PV cell converts the absorbed sunlight energy into electricity
4) Movement of the electron as a result of added energy creates two charge carriers, an electron-hole pair
5) In their excited state in the conduction band, these electrons are free to move through the material.
6) Because of the electric field that exists as a result of the p-n junction, electrons and holes move in the opposite direction as expected, creating electric current
Photovoltaic System – Photovoltaic cells
FIGURE Schematic representation of a simple photovoltaic cell
Simya, O. K., et al. "Engineered Nanomaterials for Energy Applications." Handbook of Nanomaterials for Industrial Applications; Elsevier BV: Amsterdam, The Netherlands (2018).
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