• Air flow from pathogen-contaminated areas (sources of disease) can expand or increase the
spread of disease. Conditions that must be met in order to cause the spread of disease due to air
flow are high concentrations of pathogens from contaminated areas and low air exchange rates.
3.2 Relationship between ventilation and airborne disease transmission
One of the air exchanges in the building can occur through ventilation. Ventilation can be divided
into three types: natural, mechanical, and hybrid ventilation (mixed mode). Natural ventilation
utilizes openings in buildings and climatic/environmental conditions, mechanical ventilation utilizes technology (e.g., fans and exhaust), while hybrid ventilation combines both (World Health
Organization 2009). Natural ventilation has several weaknesses that can be a facilitator of airborne
disease transmission, namely (World Health Organization 2009):
• Natural ventilation is very dependent on climatic conditions and the environment around where
the building is located, consequently natural ventilation can be optimally applied in one location
but is very difficult to apply in other locations.
• It is difficult to obtain a stable air condition inside the building through natural ventilation, for
example due to changes in the difference in air pressure between outside and inside the building.
• Natural ventilation can experience various problems such as environmental conditions around
buildings that are not conducive, equipment damage (when using technology on hybrid types),
poor system planning, poor maintenance, and operation so that it cannot function properly.
3.3 Contradiction in efforts to maximize room air exchange and its solution
Utilization of ventilation to obtain high levels of air exchange and regulate the flow of air movement
in buildings is very important in reducing the risk of airborne disease transmission. But it can also
cause other problems concerning the comfort, health, and safety of humans who are in the building.
The first problem, namely natural ventilation through openings in buildings, can cause noise and
pollute air quality in the room through pollution from outside the building. The greater or more
openings, the greater the risk of noise and pollution. The second problem, in hot and humid climates
(such as tropical climates) openings can cause high humidity in the room, which triggers the growth
of mold and mildew which endanger human health. The third problem, openings can cause the entry
of insects, wild animals, and even increase security risks. The fourth problem, openings that apply
the principle of cross-air circulation (continuous opening from one room to another) can cause
difficulties in meeting safety standards in the event of a fire (room protection from fire spread) and
fire smoke control standards (World Health Organization 2009). Efforts to overcome the problems
above can be reached in several ways. First, in the initial stages of planning the site design, building
(shape, orientation, and layout) and building envelope must be carefully considered to maximize
air exchange in the space but also reduce the risks that may arise due to openings. Second, at the
beginning of building design, positioning, magnitude, and type of openings are very important
to maximize air exchange. Third, the selection of light barriers outside the building that is right
affects the comfort of the temperature inside the room. Fourth, the selection of the right building
material (both for exterior and interior) is also important to achieve a comfortable temperature
in the room. Fifth, the use of hybrid ventilation can help solve the problem of safety risks and
maintain the stability of the exchange rate and the direction of air flow in the building (World
Health Organization 2009).
3.4 Air Conditioning (AC) and its relationship with airborne disease transmission
Based on research, the AC system can be a facilitator of airborne disease transmission but can
also reduce the risk of transmission through (European Centre for Disease Prevention and Control
2020):
• An AC system that uses the right filter can filter droplets and even droplets of the nuclei from
SARS-CoV-2.
116
spread of disease. Conditions that must be met in order to cause the spread of disease due to air
flow are high concentrations of pathogens from contaminated areas and low air exchange rates.
3.2 Relationship between ventilation and airborne disease transmission
One of the air exchanges in the building can occur through ventilation. Ventilation can be divided
into three types: natural, mechanical, and hybrid ventilation (mixed mode). Natural ventilation
utilizes openings in buildings and climatic/environmental conditions, mechanical ventilation utilizes technology (e.g., fans and exhaust), while hybrid ventilation combines both (World Health
Organization 2009). Natural ventilation has several weaknesses that can be a facilitator of airborne
disease transmission, namely (World Health Organization 2009):
• Natural ventilation is very dependent on climatic conditions and the environment around where
the building is located, consequently natural ventilation can be optimally applied in one location
but is very difficult to apply in other locations.
• It is difficult to obtain a stable air condition inside the building through natural ventilation, for
example due to changes in the difference in air pressure between outside and inside the building.
• Natural ventilation can experience various problems such as environmental conditions around
buildings that are not conducive, equipment damage (when using technology on hybrid types),
poor system planning, poor maintenance, and operation so that it cannot function properly.
3.3 Contradiction in efforts to maximize room air exchange and its solution
Utilization of ventilation to obtain high levels of air exchange and regulate the flow of air movement
in buildings is very important in reducing the risk of airborne disease transmission. But it can also
cause other problems concerning the comfort, health, and safety of humans who are in the building.
The first problem, namely natural ventilation through openings in buildings, can cause noise and
pollute air quality in the room through pollution from outside the building. The greater or more
openings, the greater the risk of noise and pollution. The second problem, in hot and humid climates
(such as tropical climates) openings can cause high humidity in the room, which triggers the growth
of mold and mildew which endanger human health. The third problem, openings can cause the entry
of insects, wild animals, and even increase security risks. The fourth problem, openings that apply
the principle of cross-air circulation (continuous opening from one room to another) can cause
difficulties in meeting safety standards in the event of a fire (room protection from fire spread) and
fire smoke control standards (World Health Organization 2009). Efforts to overcome the problems
above can be reached in several ways. First, in the initial stages of planning the site design, building
(shape, orientation, and layout) and building envelope must be carefully considered to maximize
air exchange in the space but also reduce the risks that may arise due to openings. Second, at the
beginning of building design, positioning, magnitude, and type of openings are very important
to maximize air exchange. Third, the selection of light barriers outside the building that is right
affects the comfort of the temperature inside the room. Fourth, the selection of the right building
material (both for exterior and interior) is also important to achieve a comfortable temperature
in the room. Fifth, the use of hybrid ventilation can help solve the problem of safety risks and
maintain the stability of the exchange rate and the direction of air flow in the building (World
Health Organization 2009).
3.4 Air Conditioning (AC) and its relationship with airborne disease transmission
Based on research, the AC system can be a facilitator of airborne disease transmission but can
also reduce the risk of transmission through (European Centre for Disease Prevention and Control
2020):
• An AC system that uses the right filter can filter droplets and even droplets of the nuclei from
SARS-CoV-2.
116