BUILDING SERVICES I
TOPIC: INDOOR
ENVIRONMENTAL
QUALITY IN OFFCIE /
HEALTHCARE
PREPARED BY: TAN KIAH CHUN (0324414)DARREN LOONG CHI YOONG (0318029)TAN ZHAO MING(0318724) KONG ZHEN CHUNG(0319528)YONG SING YEW(0318766)THAN LEK MEI (0315538)
INDOOR ENVIRONMENTAL
HEALTH QUALITY IN OFFICE• Indoor environmental quality (IEQ)
refers to the quality of a building’s environment in relation to the health and wellbeing of those who occupy space within it.
• IEQ is determined by many factors, including lighting, air quality, and damp conditions.
• Other factors such as indoor temperatures, relative humidity, and ventilation levels can also affect how individuals respond to the indoor environment.
INDOOR ENVIRONMENTAL
QUALITY (IEQ) IN OFFICES
APPLICATIONS AND SYSTEMS
AIR CONDITIONER Abbreviated as “AC”
It is referred to Heating, Ventilation, and Air Conditioning
(HVAC) in construction term.
Used to distribute conditioned air in an enclosed space
to improve thermal comfort.
Usually used to lower the temperature of an enclosed
space.
AIR CONDITIONER IN OFFICES
Why is it essential? Because most offices today are of high rise buildings,
therefore natural ventilation is impractical.
Air conditioner can also control the humidity of an
enclosed space.
Since humans perspire to provide natural cooling by the
evaporation of perspiration of the skin, drier air improves
the comfort provided.
AIR CONDITIONER IN OFFICESChoosing the right type of HVAC system:
Must select the appropriate type and size of air conditioning system.
If it is not appropriate, it will not be able to cool the space properly.
It can cause a decrease to employees’ productivity due to
uncomfortable environment.
TYPES OF AIR CONDITIONERS
Cooling Only Split-System
Cooling Only Packaged-System
TYPES OF AIR CONDITIONERS
Heat Pump
Chilled Water System
TYPES OF AIR CONDITIONERS
Window Air Conditioner
Packaged Terminal Heat Pump
SYSTEM OF AN AIR CONDITIONER
Three (3) main parts of a standard air conditioner:
1. Cooling Tower
Similar to the condenser of a home-use air conditioner.
Usually air conditioners that are installed for high rise buildings such as
offices will have a cooling tower in place on the roof of the building.
It is common to use both a chemical refrigerant as a coolant that evaporates
and also chilled water to lower the temperature of the coolant.
2. Compressor
To circulate the refrigerant In the system under pressure, this
concentrates the heat it contains.
At the compressor, low pressure gas is converted into high pressure
gas.
3. Air Handling Unit (AHU)
It is the most important component in a commercial HVAC system because
it circulates and regulates the cooled air throughout the building.
AHU looks like a large metal box containing a blower, heating or cooling
elements, filter racks or chambers, sound attenuators and dampers.
There is always a room for the AHU at every floor of a high rise office
building.
An efficient AHU can move significant amounts of air quickly throughout the
building.
SYSTEM OF AN AIR CONDITIONER (CONT’D)
A diagram showing the HVAC system in a office building.
DAYLIGHTING
Daylighting is a system used to allow natural daylight into a
building.
It is a simple system as it only requires several openings
with windows or glass panels to allow light to penetrate.
Helps to create a visually stimulating environment for
building occupants.
INTRODUCTION TO DAYLIGHTING (CONT’D)
Daylighting can be used to substitute electrical lighting
during the day, therefore it can help to cut down one third
of total building energy costs.
In order to create an effective daylighting system, the
location of windows or skylight has to be designed in
such a way to avoid direct admittance of direct sunlight
into occupants’ eyes.
Blinds and shades can be used to minimize direct
sunlight that can affect the comfort of occupants in the
building.
There are various types of daylighting systems but most
of the office buildings uses either tubular daylighting
device or horizontal daylighting system.
TUBULAR DAYLIGHTING DEVICE
A tubular daylighting device or TDD in short, is an optical system that uses
engineered duct-like tubes to carry light from roof openings deeper into the
building.
The tubes ranges from 10 to 21 inches in diameter and has a engineered
reflective surface and an interior diffuser inside the tubes.
TDDs are frequently capped with a transparent, roof-mounted dome that
acts as a light collector.
The diffuser is used to distribute even amount of light inside a building.
TDDs may look simple, but it is one of the most advanced daylighting
technologies among the other daylighting systems.
TUBULAR DAYLIGHTING DEVICE
(CONT’D)
A diagram showing how light travels into a
Tubular Daylighting Device (TDD) and how
it is distributed inside a building.
HORIZONTAL DAYLIGHTING
SYSTEM This is a even more simple and traditional daylighting system.
Horizontal systems uses rows of transom-level wall mounted panels to
harvest light from the sides of a building and deliver it horizontally to
adjacent floors.
This is similar to an exterior air handling unit distributing fresh air through a
building.
The horizontal daylighting system resembles a conventional mechanical
heating and ventilation system, carrying light from one point to different
parts of a building through a network of duct-like passages.
Since more light enters the building using this daylighting system, blinds are
needed to avoid heating in the building. Blinds are also needed to avoid any
direct sunlight on task surfaces or into the occupants’ eyes.
HORIZONTAL DAYLIGHTING SYSTEM (CONT’D)
Horizontal daylighting system uses specially shaped lenses, called
Fresnel lens, which are powerful but shallow, to collect and concentrate
sunlight from oblique angles.
Light captured by the wall panel is increased by a factor of 10, and then
sent through a network of fanning reflective light pipes into horizontal
above-ceiling ducts, and finally delivered to room diffusers.
Installation
process
Split air conditioners are the commonly used
ventilation system in office because there are
comparatively cheap and easy to install.
Method 1 of 3: Install the
Indoor Unit
1) Select an unobstructed location on your interior wall to
mount the indoor air conditioning unit.
2) Secure the mounting plate to the interior wall.
3) Create a hole in the wall to fit the piping.
4) Check the electrical connections.
5) Connect the pipes.
6) Secure the indoor unit to the mounting plate by pressing the
unit against the mounting plate.
Method 2 of 3: Install the Outdoor
Condenser
1) Choose the best place to install the outdoor unit.
2) Lay the concrete pad on the ground and make sure that it
is level.
3) Connect the electrical wires.
4) Secure the pipes’ flare nuts to the
corresponding pipes on the outdoor unit.
Method 3 of 3: Complete the Split
System Air Conditioner Installation
1) Bleed the air and humidity from the refrigerant circuit.
2) Wrap the joints of the piping with insulating covering and
insulating tape.
3) Affix the piping to the wall with clamps.
4) Seal up the hole in the wall using expanding
polyurethane foam.
Tubular daylight devices
Tubular daylighting device (TDD) are devices that you can use
to get natural light into rooms that don't have access to
windows or traditional skylights. They do this by collecting
sunlight on the roof and channeling it through a highly-
reflective tube into the room below. This daylighting solution
is perfect for dark hallways, bathrooms, and kitchens.
1) Choose the Right Location
• Choosing the right location to install your
skylight will go a long way in avoiding any
potential installation problems and providing
a better final result.
2) Cut Out Ceiling and Roof Holes
• Once you've finalized the location for your
skylight, it's time to cut the holes in the
ceiling and the roof.
3) Install the Flashing
• Now that the roof hole is cut, you will need to install the flashing.
4) Install the Tube
• Once the flashing is installed, you're ready to build and install the tube.
5) Install the Dome
• Attach the dome to the flashing using the screws provided in the installation kit.
6) Install the Diffuser
• Attach the diffuser and trim ring to the ceiling ring.
Diagram of Tubular Skylight Installation
PROBLEMS
Indoor environmental quality not necessarily from air
• Noise
• Lightning
• Ergonomic stressors
• Job-related psychosocial stressors can
• Individually and combination
Problem
• Office operation intended to reduce short-term costs will contribute the problem
• Lack use of walk mats at entrance- increase amount of soil tracked
• Low-bid custodial service that fail to remove soils and containment- increase the load of volatile organic chemicals
• Renovation and remodeling can effect the indoor environment
Negative effect on air quality
• Reducing the flow of outdoor ventilation air
• Shutting down HVAC system unoccupied periods
• Select least expensive and least efficient panel filters
Effective design and construction of office
• Properly designed and constructed building shell-isolates and insulates the indoors from the outdoors
• Keeps outdoor containments such as dust and liquid water enter the office
• Insulation in the office helps to protect the interior temperature extremes
Well designed heating, ventilation and air-conditioning (HVAC) system
• Provide clean outdoor air
• Modify and control indoor temperature
• Dilute general pollution from people, activities, furnishings
• HVAC system-maintain correct air pressure relationship between indoor and outdoor
Effective, prompt and preventive maintenance
• Reduce the occurrence of problems with the indoor environment
• Careful management of custodial, pest control, building engineering and maintenance service-prevent problem
Change the floor plan
• Moving walls or change in number and distribution of people-may deviate from intended design and operation of HVAC system
• Short term problem maybe reduced
• Such as painting during unoccupied periods and airing out carpets before installation
Pollutant source control
• Most cost-effective solution to IEQ problems
• Prohibit tobacco smoking in office
• Changing air pressure relationship will help to isolate sources
• Good filtration help prevent outside pollution pollen from entering the building
• Minimize the use of perfumes or colognes
• Do not do the activities such as cooking food in microwave ovens
• May trigger a co-worker’s discomfort
• Chemical formulations should be used sparingly-only when dedicated ventilation is provided.
• Air supply diffusers should not be blocked or taped closed
Case
Study
INDOOR ENVIRONMENTAL
QUALITY IN OFFICES
Indoor Environmental
Conditions
In 2004, Professor Dr. Alan Hedge from Cornell University conducted a study at
Insurance Office of America’s headquarters in Orlando.
Aim of study – To investigate the link between changes in physical environmental
conditions and changes in work performances
Methods
The office were equipped with air samplers that recorded
the temperature every 15 minutes
Tracked the productivity of 9 workers working in the
office
Productivity was tracked by software that measure their
typing speed and error for 20 consecutive days
Result
The workers were significantly more productive when the office
temperature was kept at a warmer temperature.
Office temperature at 25°C – workers keying 100% of the time with
a 10% error rate.
Office temperature at 20°C – keying rate went down to 54% of the
time with a 25% error rate.
It show clear associations
between office work
performance and indoor
environmental conditions.
The performance of workers
will decrease when it is too
cold (or too hot).
Temperature at a more
comfortable thermal zone
will improve performance of
workers.
Impact of Daylight
A study from Northwestern University Feinberg School of Medicine.
Aim of study – To understanding the impact of light on office workers.
Methods
Total of 49 participants were examined.
27 of them worked in windowless offices and
another 22 were worked near windows.
Workers with windows received 173% more white
light exposure during work hours.
Result
Workers with windows in the workplace slept an average of 46 minutes
more per night than others who did not have the natural light exposure in
workplace.
More physical activity than those without windows.
Workers without windows had more sleep disturbances.
May suffer memory loss, depression, slower psychomotor reflexes and
shorter attention spans.
Daylight can improve office workers productivity and health
Advantages and
DisadvantagesAdvantages Disadvantages
Increase comfort • Cost of construction will
be high
Decrease absence rates • Special design from
architect and engineer
Increase work
performance
• Maintenance cost is high
Pollutant inside building
can be diminished
• Specific materials always
needed to construct
Maintain optimum
temperature for workers
• Once the building is built, changing the existing construction is very hard
Improve overall thermal
comfort
• Hard to satisfy everyone's preference for desired temperature
Decrease sick building
syndrome
• adding new lights like fixed ceiling lights could be a lot more difficult
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