Hand Sanitizer Experiment

I. Introduction: Microbes are everywhere in our environment and are present all over our bodies. Transient microbes can be passed from person to person, and this is characteristic of opportunistic pathogens (Boyce & Pittet, 2002). The germ theory states that microbes have the ability to cause diseases. The purpose of this experiment was to investigate the microbes found on my hands, learn about the importance of spreading microbes and diseases, and investigate the effectiveness of hand washing and hand sanitizer on killing or reducing microbial growth. The fact that we use aseptic techniques and hand washing is because of this germ theory and we need to use these techniques to reduce contamination and spread of microbes and diseases, especially …show more content…
The null hypothesis was that washing hands with only water, washing hands with soap, or using hand sanitizer would have no effect growth of microbes. First to test for outliers in my data I used the five number summary. There was a mild outlier (110) detected in the hand sanitizer group, but was not removed because it did not drastically skew the results. The first bar graph (seen in the data section of paper) can be used to compare data. The first bar graph includes standard error bars that provide visual evidence (along with another test) on whether or not there is any significant difference between the means by looking at their overlap. Based on the visually examining the bar graph, there are standard error bar overlapping between the means and therefore it can be said there is no statistically difference between the …show more content…
I was expecting there to be less microbial growth after using hand sanitizer, because the hand sanitizer works by denaturing proteins making it very difficult for growth to occur (Boyce & Pittet, 2002). This turned out not to be the case when I observed the colonies growing on my Petri plate dish. Based on observation on my Petri plate I had more growth of colonies on quadrant D (hand sanitizer technique) than any other quadrant, and this sort of disproves the notion that hand sanitizers kill 99.9% of germs. Clearly the hand sanitizer did not kill 99.9% of germs on my hands. Several other groups had opposite results, showing significantly less growth for the hand sanitizer method. My differences could be due to error, not washing long enough, or not covering all the areas of my hands with hand cleanser. For future experiments, I would not change any of my methods but would be more careful when it comes to making sure I wash my hands more thoroughly for better