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 5 RECIRCULATION VS. VENTS 5 THE HUMAN EFFECT 6 SYDNEY BUSES 6

AIM 7

HYPOTHESIS 8

CONSIDERING APPROACHES 10

RISK ASSESSMENT 10

METHODOLOGY 11

VARIABLES 12 INDEPENDENT VARIABLES 12 DEPENDENT VARIABLES 12 CONTROLLED VARIABLES 12

APPARATUS 12

RESULTS 14 RISES 15 FALLS 18 EXAMPLES 21

ANALYSIS 25 DIFFERENCE FROM THE STARTING POINT 28 FINDING AN EQUATION 29 RISES EQUATION 30 FALLS EQUATION 32

DISCUSSION 34 AN EXHAUSTIVE EXPERIMENT- FURTHER RESEARCH? 34 THE EQUATIONS 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.

BREATHE EASY 3 2014 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…

BREATHE EASY 4 2014 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

4http://www.lsmtechnologies.com.au/item.cfm?category_id=2483&site_id=14 5 http://papers.sae.org/2008-01-0829/

BREATHE EASY 5 2014 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/crowded- buses-co2-levels-ten-times-higher-than-outside-and-hills-commute-among-worst/story- fngr8i1f-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.

BREATHE EASY 7 2014 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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BREATHE EASY 9 2014 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.

BREATHE EASY 10 2014 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)

BREATHE EASY 11 2014 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.

BREATHE EASY 13 2014 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 people- rises, 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.

BREATHE EASY 14 2014 Rises

2 People

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Examples

BREATHE EASY 16 2014 4 People

BREATHE EASY 17 2014 Falls 2 people

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4 People

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6 People

BREATHE EASY 20 2014 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.

BREATHE EASY 24 2014 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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BREATHE EASY 27 2014 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.

BREATHE EASY 29 2014 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.

BREATHE EASY 31 2014 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.

BREATHE EASY 33 2014 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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