Breathe Easy
By Chanum Torres
A study on the levels of CO2 in vehicle cabins.
Redeemer Baptist School
Year 10 2014
Table of Contents
ABSTRACT
3
INTRODUCTION
4
BACKGROUND RESEARCH
5
THE BUILDUP
RECIRCULATION VS. VENTS
THE HUMAN EFFECT
SYDNEY BUSES
5
5
6
6
AIM
7
HYPOTHESIS
8
CONSIDERING APPROACHES
10
RISK ASSESSMENT
10
METHODOLOGY
11
VARIABLES
12
INDEPENDENT VARIABLES
DEPENDENT VARIABLES
CONTROLLED VARIABLES
12
12
12
APPARATUS
12
RESULTS
14
RISES
FALLS
EXAMPLES
15
18
21
ANALYSIS
25
DIFFERENCE FROM THE STARTING POINT
FINDING AN EQUATION
RISES EQUATION
FALLS EQUATION
28
29
30
32
DISCUSSION
34
AN EXHAUSTIVE EXPERIMENT- FURTHER RESEARCH?
THE EQUATIONS
34
35
CONCLUSION
36
APPLICATION
37
THE WORKING MODEL
37
ACKNOWLEDGEMENTS
38
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Abstract
Breathe Easy is a scientific investigation on the levels of CO2 within vehicle
cabins. Spanning several months, the research looked into the extent of CO2
buildup and looked at a primary factor to this said buildup. Gathering data and
reaching conclusions involved observing and analyzing dozens of ‘logs’ or
graphs generated form data automatically collected by a data logger.
Conclusions were reached primarily through mathematical processes, yielding
figures that served as evidence for hypothesized points. The main finding was
that the number of passengers directly affects the level of CO2 reached in the
vehicle cabin. The buildup of CO2 also occurs primarily when the A/C is set to
recirculation, as the same air is cycled throughout the cabin. From the results
gathered, two equations (one for the rise of CO2 and one for the fall) were
generated and give a rough idea of what levels CO2 will be reached provided
the number of passengers and duration is known. For example substituting the
values 2 for the number of people, 4 (minutes) for the duration into the rise
equation, it can be seen that a level of ppm >1000ppm is already reached. With
2 people in 2 minutes, CO2 can be expected to drop by 1000ppm. As fresh air
is constantly being brought in under ventilation, levels of CO2 that could pose a
negative impact on human health are not reached .The equations are not
definitive but communicate the connection established between time, the
number of people and the levels of CO2. An automatic cycle has been found to
be present in cars. This cycle involves the A/C starting on recirculation,
running as so for a period of time then automatically switching to ventilation,
resulting in a drop of CO2. This cycle has been found to be insufficient in
maintaining good air quality as levels of up to 8000ppm had been recorded.
This project uses the ASHARE standards as a reference point for what CO2
levels are recommendable, unsafe etc. and how these levels may impact a
human .This report details the genesis of this project, the processes undertaken
before and during the data gathering, the results, conclusions, real-world
applicability and future direction.
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Introduction
My first exposure to the term “ppm” or parts per million was on the National
Geographic website. I came across an article on a warming Earth and higher
levels of Carbon Dioxide, 400 parts per million, in the air. At the time I was
searching for inspiration, inspiration for a topic I could perform a Science
Project on. In 2007, I was the Primary Winner in Australia for my research on
air quality in my local area. Naturally, I was drawing on ideas from the past to
assist me in the present. I was fairly certain an environmental-related project
was the way to go, especially in relation to the air. CO2 is indeed a problem on
a global scale but so much research had been done on this. I was looking for
something that was a problem in everyday life, something practical, applicable
and something not given much thought. I started to read about CO2 and its
buildup in indoor environments. Mentioned in several studies were the health
side-effects brought about by exposure to higher levels of CO2. The Air
Conditioning was a major factor in the buildup of CO2 in indoor spaces. Many
articles actually defined acceptable and dangerous levels in terms of ‘ppm’. I had
not realised the impact the level of CO2 in air we breathe could have on
immediate health. I had never seen it as a problem, an issue to be addressed. At
this time, the holiday season was starting and traditionally, the number of road
accidents spike at this time of the year. Driver fatigue is often to blame for the
wrecks left on the side of the freeways. Fatigue, nausea, headaches were all
brought on by high levels of CO2. I connected the dots, the different strands of
thought in my mind and an idea was born. Was not a car cabin an indoor
environment as well? Don’t cars have Air Conditioning? Could the CO2
buildup in cars be at a level that could affect the driver? People I discussed this
with at first were skeptical. They said that cars were designed to bring in
adequate amounts of fresh air. Dangerous levels of CO2 would not be reached.
Well, there was only one way to find out…
And so the research began…
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Background Research
The Buildup
The articles I read concerning the buildup of CO2 were predominately
looking at office spaces, classrooms and work spaces. 1There have been
standards established, outlining echelons of CO2 ppm and their
respective effects on health by ASHRAE ( American Society of Heating,
Refrigerating, Air Conditioning Engineers), a reputable society whose
work is trusted and referred to by organisations globally2. It is generally
accepted that a level <1000ppm is normal, hence ‘safe’. Levels between
1000ppm and 2500ppm bring on general drowsiness. On the roads, a
split second of being unfocused could have dire consequences. Levels of
2500ppm-5000ppm bring on adverse health affects such as nausea and
headaches. Levels above 5000ppm are highly dangerous and exposure to
these levels should not be prolonged. In indoor environments this buildup
has been observed, one study even showing that it could be affecting
cognitive ability3.This buildup has been established to be active in indoor
spaces, consequently, this would hold true for vehicle cabins. They too
are indoor environments: sealed, air-conditioned and have people within
them. The standards would apply here as well. There were a number of
scientific research papers I read that had looked into this buildup of CO2
in vehicle cabins. Two articles, one a research paper summary another an
information bulletin page , directly applied to what I intended to do and I
was extremely interested by what they had to conclude.4 5 Both stated
that increased levels of CO2 had negative effects on occupants including
fatigue, micro-sleeps, acidosis and reduced concentration. All these have
the potential to cause a road tragedy. They also attributed the buildup of
CO2 to the number of occupants.
Recirculation vs. Vents
These two settings played an integral part in this project. Using the
Ventilation setting in the A/C brings air from outside, cools it down and
blows it into the car. Fresh air from outside is constantly being brought in.
Recirculation mode however, brings air from outside, cools it down and
1http://www.energy.wsu.edu/Portals/0/Documents/Measuring_CO2_Inside_Buildings-Jan2013.pdf
2ASHRAE
Standard 62.1-2013
3(https://www.sciencenews.org/article/elevated-carbon-dioxide-may-impair-reasoning
4
http://www.lsmtechnologies.com.au/item.cfm?category_id=2483&site_id=14
http://papers.sae.org/2008-01-0829/
5
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this volume of air is constantly blown around the car. The vents are shut
and so the same air circulates.
The Human Effect
The air exhaled by humans is composed of several gases, including CO2.
The odors given off by humans also contain CO2. These can be called
bioeffluents. They have an effect on the CO2 levels: contributing to the
buildup of CO2 in an environment. With the A/C on recirculation,
replacing the oxygen with CO2 and several passengers in the car also
giving off their own CO2, the results could be very interesting.
Sydney Buses
Buses in Sydney’s Hills District are notorious for being extremely crowded at
peak hours. Mr Shane Van Der Vorstenbosch, a director at OnSolution, a
company selling air quality monitoring equipment, recently measured levels of
CO2 on the said buses.
“Mr Van De Vorstenbosch said that higher carbon dioxide levels lead some
people to feel fatigued, nauseous, sleepy” and even get headaches.
Mr Van De Vorstenbosch recorded levels between 505 ppm and 3500 ppm
recently on Hills bus routes to the city, compared to an outdoor reading of
between 345 ppm and 585 ppm.”6
The article that this came from in the Daily Telegraph was very relevant to
what I intended to research. It directly linked the number of passengers to the
levels of CO2. It had been established that there was indeed a buildup of CO2
to levels deemed unsafe in comparison to the ASHARE standards in buses.
I commented on the article, outlining research I had already conducted as by
the time I read the article in March 2014, my logging was well underway. This
article assured me that I was onto something interesting, that my research was
valid and applicable.
6
See the full article here: http://www.dailytelegraph.com.au/newslocal/the-hills/crowdedbuses-co2-levels-ten-times-higher-than-outside-and-hills-commute-among-worst/storyfngr8i1f-1226847846286?nk=35ee43b350d117ec4e544535c9c1cb00
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Aim
1. To determine the extent of CO2 buildup within a vehicle’s cabin and how
quickly levels of CO2, which could potentially affect the driver primarily as
well as passengers ,would be reached.
2. To determine how quickly levels of CO2 return to a level that is safe when
fresh air is brought in.
3. To develop an invention that automatically prevents the CO2 levels from
building up to a critical level7.
7
See the Design Folio for the process undertaken to achieve this aim.
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Hypothesis
CO2 builds up at a faster rate than people realise. The fresh air that is brought
in on the recirculation mode is not adequate and dangerous levels of CO2 are
still present .I hypothesise that the discomfort felt my people in the car after a
prolonged period, which may be headaches, nausea, fatigue are due to a
buildup in the levels of CO2 in the air. This level can be reached within 30
minutes. The period in which a dangerous level of CO2 is reached will be
shorter when the A/C is set to Recirculation, and longer when set to
Ventilation. I hypothesise this as Recirculation keeps the same air in the cabin,
whereas Ventilation constantly brings in air from outside so dangerous levels of
CO2 will not be reached. I further hypothesise that the number of people inside
the car affects the levels of CO2 as humans breathe out and give off CO2. The
higher the number of people the higher the readings of CO2. The following
graph8 illustrates this concept:
Out door air mode translates as
Ventilation. It can be observed that levels
of CO2 do not surpass 1000ppm. The
number of occupants affects the level of
CO2 reached. The more occupants, the
greater the concentration of CO2. A drop
on occupants consequently means a drop
in the level of CO2. Notice the higher CO2
concentration reached under Recirculation
in the below graph. Once again, the rise
and fall of CO2 corresponds with the rise
and fall of the number of occupants..
8
The graphs above are from ‘Sick Buildings: Definition, Diagnosis and Mitigation’ by Dr
Thad Godish published in 1994. It is an extensive study on indoor air quality.
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Considering Approaches
There were several ways in which measuring the CO2 inside a vehicle cabin
could have been undertaken.
1. A simulation. Using a room or some environment with A/C settings
required that simulates a car and conducting the measurements there.
2. Electronic simulation. Using a computer program to generate figures for
the levels of CO2 reached based on data inputted eg: number of people
or the duration of the log.
3. Using a car. Sitting in a car during a regular drive and measuring the
CO2 as normal commute occurs.
I decided to use method 3 to conduct this experiment so that the results
yielded would truly reflect real-life. I believed that to get results that were
authentic as possible, it was necessary to actually be involved what goes on in
the car, rather than just speculate or draw up simulations. The drawback to
this was that controlling the experiment would be quite difficult. The nature
of the roads is such that no two drives are exactly the same. The road
conditions, car type, passenger type, ever changing temperature and the fact
that a car was not designed to be a sealed, sterile science laboratory would all
have to be considered.
Risk Assessment
The risks to humans in this experiment are not high. This is because humans
are taken part in activities that they would normally partake in, on a daily basis.
What is being tested is the level of CO2 in the vehicle cabin. It has already been
established that certain higher levels of CO2 can have negative effects on
humans. I have no need to establish this as it has already been established in
numerous studies and is generally accepted.
Nevertheless, consent forms have been drawn up for anyone who has sat in the
vehicle cabin while logging has occurred to sign, saying that they agree to take
part in the research and that they understand the results will be published.
In light of my hypothesis that there will indeed be a buildup of CO2 under the
recirculation setting, I do not intend to ‘force’ the A/C. This means that if I or
anyone in the vehicle feel the need to open a vent to let fresh air in, then they
may do so. After all, this is not an experiment on humans and their safety and
comfort is paramount.
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Methodology
These are the steps I took to measure the levels of CO2 in the cabin of the
vehicle with the data logger.
1. Record relevant, initial background details on Data Sheet.
2. Start up computer and open GasLab software. Ensure all equipment is in
order.
3. Start the log, taking down the appropriate information at 5 minute intervals
on the Data Sheet*.
4. End the log when required and save the file to destination folder.
5. Input data into Microsoft Excel template (Master graph)
6. Graph will be generated showing relation between time (x axis) and levels of
CO2 (y-axis).
*Every 5 minutes I recorded these details: Temperature, Humidity, Number of
Passengers, A/C settings (on/off, vent/recirc, fan speed) and anything worth
noting e.g.: “window opened at 10am” or “door left open for 5 minutes” etc.
Note: While I am performing the log and taking down details, the A/C is
running as normal throughout as it would in a normal car trip.
In conjunction with the digital logging of the levels of CO2, I also drew up a
Data Sheet on which I recorded manually the various details listed above. (see
below for an example)
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Variables
Independent Variables
-For each car model, the main independent variable was the number of people
in the car cabin during the log
-For the duration of most trials the A/C was set to recirculation. In some
selected experiments the A/C was switched to fresh and others the A/C was left
on fresh to determine baseline levels.
Dependent Variables
-The levels of CO2 reached during the log.
Controlled Variables
-Same data logger used in every log conducted.
-Position of the data logger (front passenger seat).
-Small passenger pool means the same people for the majority of logs.
Apparatus
Listed here are the instruments I used to conduct this experiment.
Data Logger and Gaslab Software
The Data Logger took measurements of CO2 in
the air, feeding the data to the laptop connected
to it. GasLab software was the interface between
the user and the Logger allowing the user to
control it.
Windows Based Laptop
Used to run the Gaslab Software and store the
log files. Connected to the Logger.
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Temperature/Humidity Sensor
With these I obtained the relevant
measurements of temperature and humidity.
Car A/C system
Switched between recirculation, ventilation.
MacBook Air
Where all data was moved, analysed, stored
and presented.
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Results
After dozens of tests, equating to hours of sitting in the front seat watching
graphs on laptop screens and taking measurements, I drew up Data
Compilation spreadsheets.
I made two such spreadsheets: one for rises of CO2 and one for the fall of CO2
levels. Periods of time where growth was sustained, steady and occurred for a
reasonable amount of time were identified. The same criteria applied for the
falls.
The CO2 values at 2 minute intervals were entered into a spreadsheet. These
figures were then formatted into tables. Where the rise or the fall began was
called “0 min”. Subsequent columns were called “2 min”, “4 min” etc.
Each table was specific for a certain number of people in the car cabin and what
the setting of the A/C was (vents/recirc). Hence there were tables for 2 peoplerises, 4 people-falls etc.
The values for each 2 minute interval (column) were then averaged. These
average values were then used to generate the graphs seen in the Data Analysis
section.
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Rises
2 People
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3 People
Examples
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4 People
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Falls
2 people
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4 People
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6 People
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Examples
These logs are ideal in that they ideally represent trends observed across the
logs. The graph line helps to visualize this.
This Log entitled “Ex 24” is from the 10th April 2014. On the y axis is marked
out the CO2 ppm values. The x axis is marked out with the time. A clear rise in
the levels of CO2 can be observed. This is followed by a drop in the levels of
CO2. It is these periods of growth and fall that I used as results.
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This Log entitled “Ex 25” is from the 11th April 2014. It is very similar to Ex 24
on the previous page. An obvious buildup of CO2 can be observed, once again
followed by a fall. The CO2 levels proceed to rise again.
This cycle has been observed in several of my Logs. This points toward an
automatic cycle in the A/C system. After a period of time, the vents are turned
on and fresh air is allowed in. The vents are then closed and air begins to
recirculate.
However, it can be seen that levels of CO2 climb to extreme levels. The
automatic cycle is not effective in regulating the levels of CO2.
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The two logs on the previous page were conducted on buses with up to18
passengers.
These two graphs demonstrate the relationship between the number of
passengers and the levels of CO2 within a vehicle cabin. In the top graph, as
more people board the bus, the buildup of the CO2 levels increases (note the
steeper gradient). In the 2nd graph, as people leave the bus, the CO2 levels
generally do not reach the levels they previously were at.
The higher the number of people in the vehicle cabin, the faster the buildup and
hence the higher the level of CO2 reached.
Consider the graph above entitled ‘Exp 7’. In this graph, the A/C was left on
ventilation, meaning fresh air was being constantly brought in. It can be
observed that the CO2 does not surpass 800ppm and this stays within a
recommendable level in reference to the ASHRAE standards. This graph
supports that hypothesis that since substantial volumes of fresh air are being
brought in , there is no opportunity for CO2 to buildup to levels that could
negatively impact a human.
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Analysis
The readings were compiled into spreadsheets where they were sorted by the
number of passengers, the car type and the date.
The readings were then averaged, producing graphs of the average rises and
falls of the CO2 under certain numbers of persons in the vehicle cabin.
From the average graphs, Polynomial trend lines were added to find equations
for each line.
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Difference from the Starting Point
Each graph begins at a certain level of Co2. Each graph also has as function
determining the y values (Co2 ppm). I used a spreadsheet to calculate the
difference of the levels of Co2 at 2 minute intervals from the starting
measurement.
The results are displayed in the tables below. (The tables have been generated
using the Average graphs.)
It can be observed that the higher the number of people inside the car cabin, the
greater the buildup of CO2.
Take the 14 minute mark for example. With only 2 in the car, the 14 minute
measurement differs 1328ppm from the start. With 3 people in the car cabin,
the 14 minute measurement measures 3617ppm from the start. With 4 people,
the difference is 5232ppm from the start.
This rule holds true across each 2 minute interval measured and analysed in the
above tables. These figures exemplify the relationship between the number of
passengers and the buildup of CO2.
In the same time period, there is a greater possibility of a higher level of CO2
being reached with a greater number of people in the vehicle cabin.
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Finding an Equation
I wanted to find an equation that would show the level of CO2 reached, taking
into account the number of people in the car and how many minutes the CO2
had been building up for. Similarly I wanted to find an equation for the fall of
CO2 levels. There was a major problem with this: each set of data that I
recorded into the spreadsheets started at a different level of CO2. To solve this,
I made each set of data begin at the same level for the rises, and end at the same
level for the falls: 600 ppm. To ensure that the actual rate of change in the levels
of CO2 was left unchanged, whatever I did to one number in the set, I applied
to all numbers in the set. For instance, if i subtracted 500 from a level of
1100ppm to achieve a starting point of 600ppm, then all numbers in that set
would have 500 subtracted from them.
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Rises Equation
Below are the results in table form. Each value in the same 2 minute interval
(column) has been averaged.
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By taking the ‘average’ row, a scatter graph was generated. From this scatter
graph, a linear function for each rise was generated.
The gradient, ’m’ (in the from y=mx+b) , for each linear function was then
graphed producing an exponential curve and its function.
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A final equation was then extrapolated, using the graphed gradients’ function.
y=(52.899^0.4273x) X (t)+ 600
where :
- y is the level of CO2
- x is the number of passengers
- t is the time in minutes
(note that X means multiplied by)
This equation was then entered onto a spreadsheet so that the x and t values
could be interchanged. Thus, it is possible to mathematically hypothesise what
levels of CO2 will be reached in a car cabin if the A/C is left on recirculation
with a certain amount of people in a certain amount of time. The accuracy of
this equation will be discussed in the next section.
Falls Equation
A similar process was undertaken to find an equation for the fall in CO2 levels.
The values in each row were reduced by the same number however this time it
was to achieve the same end point, instead of starting point.
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The averages were then graphed and the equations of each line were displayed
on the graph.
The m values (equations are in the form y=mx+b) were graphed and an
equation was found for this line.
The equation for the gradients was substituted into the first graph for the m
value. Notice the differing b values in the two equations in graph 1 (Average
Fall). These b values were averaged to achieve the final equation.
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y=(483.78x-3006.9) X (t) + 2974.5
where:
y is the decrease of CO2 ppm
x is the number of people
t is time in minutes
(note that X means multiplied by)
It must also be said that this equation only applies to t >1 as a positive number
is yielded.
The accuracy of this equation will be discussed in the next section.
Discussion
An Exhaustive Experiment- Further Research?
Considering the nature of the subject matter of this project, an exhaustive
project would entail a much more detailed approach, involving dozens of cars.
There would be a range of types of cars: from station wagons to sedans, trucks
to 4WD’s. In each car, there could be up to 20 types of logs performed: 1
person, recirculation; 2 people, recirculation…1 person, ventilation; 2 people
ventilation etc. Each type of log would have to be performed multiple times.
The sheer range of cars makes such a detailed study extremely hard to control,
let alone to conduct. It must also be considered that each individual cars vary
from each other. Seals on cars may be newer and thus retain more air. A/C
systems vary from car to car. Cars may have adjustments and modifications,
making them different from other cars of the same type. These factors affect the
ability to control the logging of the CO2 levels.
As well as the difference between features of cars, humans differ biologically
from each other. People breathe out different amounts of CO2 and give off
different amounts of CO2. A car full of adults will yield different results to a car
predominately full of young children with the A/C settings the same for both
premises.
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It can be seen that a perfect controlled experiment would be extremely hard to
achieve. There are too many variables involved. Further research could indeed
involve testing across a much larger range of vehicle types. Though the data
base may be much bigger, I believe the conclusions would be the same.
The Equations
In light of the points raised above, the equations that have been generated are
not entirely accurate. It must be stressed that the equation is not intended to be
definite: it is rough but it does show the relationship between time, number of
passengers and the buildup of CO2. The points marked out on the graphs vary
from the trend lines used to generate the equation. When values on the
spreadsheet tables are substituted into the equation, the answers do not
correspond . The variation ranges from minor differences to differences of
around 500ppm.
However, in essence, the graphs do communicate the intended scientific
meanings. For the Rise Equation: that the higher the number of passengers, the
higher the buildup of CO2. For the Fall Equation: the higher the number of
passengers, the slower the rate of fall in the level of CO2. Observe these tables
that have values substituted into the equations.
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Conclusion
From analysing the data gathered over the past months, the following points can
be concluded:
1. There is an identifiable buildup of CO2 in car cabins when the Air
Conditioning is on recirculation.
2. The buildup of CO2 in a car cabin under recirculation can reach levels
where a human’s health may be affected.
3. The higher the number of people in the car cabin, the faster the rate of
buildup in CO2 levels and thus a higher the level of CO2 is reached. The
number of people within the vehicle cabin does have a direct affect on the
levels of CO2.
4. Generally, if the A/C is on ventilation, dangerous levels of CO2 will not be
reached, regardless of the number of people in the car cabin.
5. The equation y=(52.899^0.4273x) X (t)+ 60 can be used to give an idea of
when a dangerous level of CO2 will be reached under Recirculation,
considering time and the number of people in the car. This is achieved by
substituting the desired values into the equation (see page 30).
6. The equation y=(483.78x-3006.9) X (t) + 2974.5 can be used to give an idea
of how far levels of CO2 will fall when the A/C is switched to ventilation
after a buildup considering time and number of people in the car. Again,
this is achieved by substituting the appropriate values into the equation.
7. From point 6, it is evident that the higher the number of people in the
vehicle cabin, the slower the rate that the CO2 falls. This is supplementary
to the fact that the higher the number of people, the greater the rise. They
logically complement each other.
Thus, the points that I hypothesized earlier were true. Further supplementary
conclusions have been reached.
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Application
The one thing that I believe makes this study very interesting is its practicality
and relevance to everyday life. Drivers, upon reading this report, will be made
aware of what exactly is going on in their car cabins and how this could
potentially affect them. It is something that is not given a second thought, but is
something that could save lives and prevent injuries. By being aware that there
is a buildup of CO2 to dangerous levels, a driver can take steps to prevent this
from being a hazard to him/herself and the passengers within the vehicle. A
driver can adjust how he or she will operate the A/C based on how long he
believes the drive will take and how many people will be in the cabin. The roads
are a very dangerous place where a split second could be the difference between
life and death. Any reduction in the risk posed by driver fatigue is worth the
trouble to investigate.
The automatic cycle of the A/C in cars should be adjusted to occur at more
frequent intervals. This should be done so that levels of CO2 remain in
recommended levels. At present, this cycle is still exposing people in the cabin to
levels of CO2 not deemed safe by ASHRAE.
At the very least, awareness has been raised on this topic of obvious relevance.
Further insight and study on the topic (which this project has achieved) may
open the doors for future research or move people to think about this issue that
may impact them significantly.
The Working Model
To communicate the idea that an invention of sorts could automatically prevent
dangerous levels of CO2 from being reached inside a vehicle cabin, a working
model was developed. Initially intended to be a set of automatically flashing
lights, more conceptual than actual model, the model developed over the course
of a few weeks into a true display consisting of a proper electrical circuit
complete with codes, wiring, LEDs, fans and a fish tank. The Working Model
fulfills one of the aims stipulated earlier. It automatically detects when a
predetermined level of CO2 is reached and then activates a fan to simulate the
ventilation in a car’s A/C, thus bringing in fresh air.
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Further insight into the process undertaken to develop this model and the details
behind the components of the model are contained in the Design Folio.
Acknowledgements
I would like to thank the following people for their assistance in the conduction
of this project:
Mr Stuart Garth - for mentoring me and supporting me as I completed this
project. His experience in conducting science projects has been invaluable and
has guided me these past months.
Mr Murray Garth - for assisting me with the electrical side of things. His
expertise in electrical circuits and computer programming has been of great
help in making the model and assembling the various electrical components
attached to it. Without him the model would not function as it does with all its
components and functions.
The Passengers- for sitting through the logs amounting to hours of
measurements and putting up with the scientific setup in the front of the car!
My Dad - for driving the car around, allowing me to take measurements of the
CO2 in the car. I also want to thank him for buying the materials that I needed
along the way to build the model or to complete various parts of the project.
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2014