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Title
Sudsy: Amount of Bacteria Left After Washing Your Hands

Problem Scenario
Studies show that boys tend to be more... well, gross than girls. So, noticing this, I found that I was wondering who would have more germs. This led to the question of how much bacteria is left after they wash their hands.

Broad Question
How well does hand washing work to prevent sickness?

Specific Question
How much bacteria is left on your hands after washing your hands?

Hypothesis
I think that boys will have more bacteria left on their hands after they wash them, than girls will have.

Variables
The amount of bacteria on the person's hand and the time the person will wash their hands for are both indepentant variables while the amount of bacteria left after the person washes their hands is the dependant variable.

Independent Variable:
Amount of bacteria on the person's hands and the time that they will wash their hands.

Dependent Variable:
The amount of bacteria left after the person washes their hands.

Variables That Need To Be Controlled:
The time that the person will wash their hands for.

Vocabulary List That Needs Explanation

 * Bacteria-** Bacteria are tiny organisms that are made up of a singular cell. **Model**- A simulation to show something without actually doing it for real. **Ultraviolet light**- A light with radiation lying in ultraviolet range**-** wave lengths shorter than light but longer than X rays. **Transparent Grids-** A see through piece of graph paper.

General Plan

 * 1) First, I will time people for the average hand washing times.
 * 2) Once I get that average time, I am ready to start my experiment.
 * 3) I will put 2-3 drops of Glo Germs on the person's hands and have them rub their hands together.
 * 4) I then will use a transparent grid and trace the person's hand with a sharpie.
 * 5) I will turn the UV light on, and place the hand under it with the transparent grid lying over the hand. This allows me to put a dot on the grid's intersections wherever the stain reaches.
 * 6) I then will have the person wash their hands for the average time.
 * 7) The person will then put their hand under the UV light again with the transparent grid on their palm. I will dot the areas of the hand where the stain reaches.
 * 8) After I repeat this process eight times for both boys and girls, I will count up the area of the hand, the dots **before** the person washes their hands, and the dots **after** the person washes their hands. Using several equations with those numbers, I will find the % covered before and the % covered after, which will give me my data.

Potential Problems And Solutions
The dots and area of the hand could be miscounted very easily. Check this by counting all things twice.

Safety Or Environmental Concerns
Don't let any liquids touch the UV light in case of electrical shock. Also, be careful not to drop or jostle the UV light in case of breakage. Be cautious moving in the dark room, too. Injuries could easily happen because of irresponsibility.

Number Of Trials:
16

Number Of Subjects In Each trial:
2

When data will be collected
March 2- April 2

Number of Observations:
5

Where will data be collected?:
In Mr. Biche's room and at my house.

Resources and Budget Table

 * **Item** || **Where Did You Get This?** || **Estimated Cost** ||
 * Glo Germs || Mrs. Campbell || $0.00 ||
 * ultra violet light bulb || Lowes || $10.00 ||
 * transparent grids || Mrs. Burns (reception) || $0.00 ||
 * ultra violet light || Mr. Biche || $0.00 ||
 * poster board || Staples || $5.00 ||

Background Research
I had tons of questions that had to do with my project, but really I only had three important questions that would help me with my experiment and that I couldn't answer on my own. So I did a little research and found the answers to all of the questions I wanted to ask. One question I asked myself that related to my project was how bacteria grows in the first place. After a little research I was able to find the answer to this question. When growing conditions are good, a bacterium grows slightly in size and length. Also a new cell wall grows through the bacterium, which creates two daughter cells with the same genetic material as the parent cell. If the environment is just right for the cells, the two daughter cells can divide into four cells in only 20 minutes. This growth continues all the time, so it is hard to understand why the earth isn't covered in bacteria. The main reason that bacteria doesn't overgrow, is the environment is almost never exactly right for the bacteria to grow. The environment needs to have a necessary energy source, nutrients, pH, and the perfect temperature to have that kind of bacterial growth; and that almost never happens. I also wanted to find out how antibacterial and regular soap are different. The truth is there isn't really any difference except for the price. Antibacterial soap is priced very high compared to regular soap, but the antibacterial version of soap isn't any better at killing germs than regular soap is. Therefore, most people pay a higher price for the same performance when they buy antibacterial soap. Just like regular soap, antibacterial soap also kills good bacteria and harmful bacteria both. Also, antibacterial soap takes at least two minutes to really have an effect on the bacteria growing on your hands. However, most people are not patient enough, and wash off the soap within a minute of putting it on. Therefore the soap will never truly take full effect. Still, antibacterial soap is better than regular soap in some ways. People who get their hands dirty on a regular basis, can benefit from antibacterial soap because of the germ killing ingredients. Antibacterial soap is suitable for people who work with patients and want sterilized hands, too. No matter what kind of soap you use though, it is always good to wash your hands often, to get those extra germs off. The last thing I was really curious about was the cause of mysophobia (fear of germs). The real reason people become mysophobics is basically anxiety and worry. Most people who develop this disorder have seen or heard of a tragic incident that happened or watched a seemingly benign scene from a TV show or movie. These people usually have a tendency to worry or anxiety and depression runs in the family. The disease of Mysophobia is certainly an unfortunate thing, but it is just a disease of the mind. Most off the background research I found was pretty interesting and allowed me to understand my project better. So, I am glad that I found so much information to help me with my experiment and analysis.

Detailed Procedure

 * 1) Buy or access needed supplies- poster board, UV light and bulb, Glo Germs, transparent grids, etc.
 * 2) Time people washing their hands without them knowing I'm timing them, so that the hand washing time isn't lengthened or shortened by the person.
 * 3) Pick one of the hand washing times and keep it as the time I'm going to use for the experiment.
 * 4) Go into a room that can be completely dark by just turning off the light switch.
 * 5) Have a girl put 2-3 drops of Glo Germs on her hands, rubbing them together like the Glo Germs are soap.
 * 6) Lay transparent grid over one hand,making sure that all areas of the hand are covered completely with the gridded part of the transparent grid.
 * 7) Turn off the lights so that the room is completely dark.
 * 8) Turn on UV light.
 * 9) Place hand under UV light so that light shines on hand completely.
 * 10) With an orange Sharpie for the "Before" trial, dot all of the grid points (intersections) on the transparent grid, where the stain from the Glo Germs touches.
 * 11) After dotting all of the areas where the stain reaches on the hand, have the person wash their hands with warm water and antibacterial soap for the chosen time of 22.6 seconds that was found on step 2. After washing their hands, ahve the person pat their hands dry with a paper towel.
 * 12) Place the same transparent grid used for the before trial, over the hand, making sure that the hand is completely covered with the gridded part of the transparent grid.
 * 13) Take person back in dark room and repeat steps 7, 8, and 9.
 * 14) This time, with a black Sharpie for the "After" trial, dot all of the grid points (intersections) on the transparent grid, where the remaining stain from the Glo Germs touches.
 * 15) After making sure that all of the areas where the stains touch are dotted on the transparent grid, turn off UV light and have the person wash off the remaining Glo Germs for about 1 minute.
 * 16) Repeat entire process until there is 8 "Before" and "After" trials for boys and 8 "Before" and "After" trials for girls finished.
 * 17) After getting all of the trials finished, count all of the "Before" dots, "After" dots, and area of hands, for each trial. Record the numbers in the correct places in a data table created in Google Docs.
 * 18) Put finished data table in mwvsciencefair.wikispaces.com.
 * 19) Finally analyze data.

Photo List
I need to take pictures of a hand with Glo Germs on it so that people can see how the Glo Germs look under an ultraviolet light. I also need to take a picture of the transparent grid on a person's hand and a picture of the ultraviolet light over someone's hand so that people will understand my experiment better.

All Raw Data

 * Gender || Hand || Before || % cover before || after || % cover after || % clean ||
 * Girl || 363 || 177 || 0.487603306 || 22 || 0.060606061 || -0.875706215 ||
 * Girl || 363 || 141 || 0.388429752 || 21 || 0.05785124 || -0.85106383 ||
 * Girl || 363 || 159 || 0.438016529 || 55 || 0.151515152 || -0.65408805 ||
 * Girl || 363 || 46 || 0.126721763 || 14 || 0.038567493 || -0.695652174 ||
 * Girl || 363 || 63 || 0.173553719 || 19 || 0.052341598 || -0.698412698 ||
 * Girl || 363 || 138 || 0.380165289 || 16 || 0.044077135 || -0.884057971 ||
 * Girl || 335 || 57 || 0.170149254 || 17 || 0.050746269 || -0.701754386 ||
 * Girl || 351 || 31 || 0.088319088 || 8 || 0.022792023 || -0.741935484 ||
 * Boy || 448 || 184 || 0.410714286 || 1 || 0.002232143 || -0.994565217 ||
 * Boy || 448 || 227 || 0.506696429 || 18 || 0.040178571 || -0.920704846 ||
 * Boy || 448 || 253 || 0.564732143 || 25 || 0.055803571 || -0.901185771 ||
 * Boy || 448 || 156 || 0.348214286 || 21 || 0.046875 || -0.865384615 ||
 * Boy || 448 || 137 || 0.305803571 || 17 || 0.037946429 || -0.875912409 ||
 * Boy || 448 || 148 || 0.330357143 || 9 || 0.037946429 || -0.885135135 ||
 * Boy || 448 || 88 || 0.196428571 || 4 || 0.020089286 || -0.897727273 ||
 * Boy || 448 || 147 || 0.328125 || 32 || 0.071428571 || -0.782312925 ||

Data Analysis
My data shows that boys tend to have cleaner hands after washing them than girls do. Although I at first thought that boys would have more bacteria on their hands after washing them, it turns out that boys have about 10-15% of their hands more bacteria free than girls do.

Conclusion
The percentage of bacteria that comes off of your hands after washing them is always greater than 50%. Also, I found that boys usually have cleaner hands after washing their hands, than girls do.

Discussion
My data shows that boys had cleaner hands after they wash their hands, than girls did. The percentage clean for boys was about 90- 99% while the percentage clean for girls was about 55-87% clean. That isn't a major difference, but it is definitely enough of a difference to determine which gender has cleaner hands. However, my data doesn't really support my hypothesis. I thought that girls would have cleaner hands because boys tend to be somewhat grosser than girls. But boys turned out to have at least 8-10% cleaner hands than girls did. Somethings that were easy to make a mistake on were the counting of dots on the grids and the dotting of areas that had stains on them. I came up with the solution of counting everything twice so that all of my data turned out to be very accurate. I also was really careful to get all of the areas dotted that needed to be dotted, so making a mistake while dotting the number of bacteria was taken care of too. My experiment can lead to other questions that can be researched or experimented on too. The difference between antibacterial soap and regular soap can be tested, or even how long it would take to get all of the bacteria off of your hands can be experimented for. Really this project can lead to tons of other interesting projects.

Benefit to Community and/or Science
This experiment benefits the community with health and good hygiene. If people realized that all of the bacteria on their hands doesn't come off when they wash their hands for under 1 minute, they might wash their hands a little bit longer to get those extra germs off. If people got more than 90% of the bacteria off of their hands by washing them, less bacteria would be spread, resulting in the reduction of sicknesses and disease. The reduction of sicknesses and disease would result in healthier world and less deaths. Really, there would be a chain of things responding to another in a positive way, if people washed their hands for a longer time. This experiment also benefits science with knowledge. It is good to know how much bacteria comes off of people's hands after they wash them and this experiment can lead to other experiments with questions like," How long should you wash your hands for to get all of the bacteria off of them?" or "Does antibacterial soap or regular soap get rid of more bacteria?" People and scientists are curious about how much bacteria really comes off after you wash your hands, and this experiment answers those questions.

Abstract
The main reason I thought of my question in the first place was because of my own curiosity. I was washing my hands and started to wonder how much bacteria was really coming off my hands. I sort of had an epiphany when I realized that I had just come up with my specific question. So, using the specific question, "How much bacteria is left on your hands after you wash your hands?", I started my planning for the experiment. I decided to do the experiment as a model because of the difficulties that I would have if I was doing the experiment with real bacteria. I obtained the Glo Germs and ultraviolet light from teachers and got 20 sheets of transparent grids printed out. I then started my experiment by putting Glo Germs on a person's hand and holding the ultraviolet light over the hand so that I could dot the transparent grid where the areas of the stain reach. I had that same person wash their hands for a time of 22.6 seconds and dotted the remaining areas where the stains reach under the UV light. After repeating this process 16 times, so that there were 8 trials done for both boys and girls, I analyzed my data. I ended up finding out that boys actually have more bacteria gone from their hands after they wash them, which surprised me because I thought that boys would have more bacteria left over on their hands than girls would, which I stated in my hypothesis. I also found out that the amount of bacteria that came off your hands after washing them is always above 50%. That was expected, so I was halfway right in my predictions.Towards the end of the project I was happy with my results and data, and think that overall my project is well done.