Team: 22
School: San Juan College High
Area of Science: Behavioral and Social Science
Interim: Team Number: 22
School Name: San Juan College High School
Area of Science: Behavioral and Social Science
Project Title: Comparison of COVID-19 transmission by mask and non – mask users
Problem Definition:
Today we have been thrusted into unlikely times with a global pandemic afoot and have an increased need to keep essential workers, retail workers in this case, safe as they work on the frontlines to provide necessities families need. However, there are certain individuals that have been collectively known as “Karens†on the media who actively refuse to heed to the strongly recommended health and safety guidelines issued by state legislatures and national health organizations. We will be studying how different precautionary measures can affect transmission and infection rate of retail workers to figure out what is the best way to protect customers and workers from COVID-19.
How we plan to solve the problem:
Our team has decided to restrict our simulation to the cashier area of a typical grocery store where we will create a simulation and conduct experiments to study how different precautions workers and people can take to prevent transmission from people infected with COVID-19. We will be using Netlogo, a relatively simple text-based programming language, to create our simulation. As of right now, our team is conducting research on different variables that will be included in the simulation. Due to the many variables associated with the simulation, some of which cannot be simulated such as human behavior and the random particle dispersion of droplets, we decided to include obvious variables and account for anything that could affect those variables. Variables include the following: typical conditions of a retail store (i.e. temperature, humidity, and air flow throughout the store), differing levels of precautionary measures for workers, the amount of people at a given time, diverse sets of customers, immunocompromised customers, varying ages of customers, precautionary measures taken by customers, and a simple representation of transmission.
Progress made:
As previously stated, we are currently conducting research on our variables and what things we need to take in account for our simulation. The team leader evenly split up the work among group members, who were responsible for conducting a sufficient amount of research for their assigned topics; however, due to the added pressure of high school and college work, we are having difficulty scheduling daily meetings with our group and have members who will not always be available to do their assigned topics. Members who conducted research will put a brief summary of their findings below:
Jayden (member):
I have been tasked with researching the effectiveness for varying levels of safety precautions. Safety precautions include social distancing, personal protective equipment (PPE), plexiglass shields, masks, and respirators. I started by researching how masks work and how effective different masks were at filtering out droplets from people infected with COVID-19. Masks help filter out droplets of the virus that are airborne because the virus is transmittable through the inhalation of COVID-19 droplets. My findings concluded that homemade masks, surgical masks, bandanas, and store-bought masks are not the ideal way of filtering out the virus. All of these masks only filter out 35-80% of particles. The ideal way to protect a person from COVID-19 droplets are respirators. A standard N95 respirator can filter out approximately 95% of particles; however, these masks are scarce and are usually reserved for essential works, specifically hospital workers. PPE is reserved for hospital workers because it protects them when coming in contact with COVID-19 droplets from infected patients. PPE would include gloves, protective clothing, facemasks, masks, respirators, and goggles. Social distancing is the practice of distancing oneself 6ft away from another person. The reason for this is because the average travel distance for COVID-19 droplets is approximately 6ft. It lessens the likelihood of someone getting COVID-19 from the suspected infected individual. According to the CDC, “proportion of coronavirus disease cases, hospitalizations, and deaths averted during 100 days for various social distancing scenarios in which adults reduce their contact by 25%.â€
Brandon (group leader)
I was assigned with looking into how many shoppers a cashier helps in their shift at a grocery store checkout. I would begin by finding a general figure of how many people actively shop in person during this COVID-19 outbreak. This would come to be approximately 32 million shoppers each day on average according to Credit Donkey, which credited a study from the Time Use Institute. With an estimate on how many people go to the store each day, how many people at risk in terms of shoppers, I set out to find how many of those shoppers turn up to a single cashier within a typical shift; a single shift being up to 8 hours long. I would go on to find a public forum that posted a question as to how many shoppers a cashier would serve in their shift. Due to their jobs not counting the precise number of shoppers, most were unable to respond with complete accuracy; however, this did not stop the approximation from being very close to each other. The range of approximation ranged from about 200 to 250 per shift with outliers at 75 or 100 due to variables such as being the night shift. Knowing this, we can comfortably allow variability within a range of about 150 to 275 to better factor in the lower standing averages and possibly unstated variety about 250 to account for other factors like being the closest to the exit or express lane. Coming off of this, we will need to go off the rate of, approximately, how many shoppers could be infected as well as how many have sufficient PPE.
What results are you expecting?
We predict that some of the most effective methods for reducing the spread to the cashier workers come primarily protecting the worker themselves with the higher-grade equipment. As stated, the N95 mask can filter approximately 95% of particles breathed in. Since the goal is to reduce the spread to these workers, it would make sense that the equipment that is most effective at stopping particles coming in is better used for the employee then equipment that is used to stop particles from drifting farther. With that being said, physical barriers that stop particles from going through allows the mask to not be overused as fast. Some of the best masks are made to be disposable; as such they have a point to where they become less and less affective. The use of the plexiglass barrier limits the number of particles the mask has to filter, making the mask last longer, which leads to a decreased risk of infection by using a fully exerted mask. The next requirement for the most effective way to prevent infection of an employee is the distancing of the shopper, minimum of 6ft when possible, and the use of a face mask by the shopper to reduce the distance the particles can travel. In conclusion, the most optimum set up to reduce the infection of cashiers would be the use of a superior filtration mask, preferably N95, and to decrease the number of particles reaching the mask, by decreasing distance the particles can travel and increasing the length the particles need to travel, to avoid over working the mask. 
Works Cited
Hoban, Rose. “PPE 101: How does personal protective equipment work?†North Carolina Health News, North Carolina Health News, 31 Mar. 2020, https://www.northcarolinahealthnews.org/2020/03/31/personal-protective-equipment-covid-19/, Accessed 9 Dec. 2020.
Fink, Jennifer. “9 Types of Masks and How Effective They Are.†healthgrades, Healthcare Operating Company, Inc., 18 November 2020, https://www.healthgrades.com/right-care/coronavirus/9-types-of-masks-and-how-effective-they-are, Accessed 9 Dec. 2020.
“NIOSH – Approved Particulate Filtering Facepiece Respirators.†CDC, U.S. Department of Health & Human Services, 9 April 2020, https://www.cdc.gov/niosh/npptl/topics/respirators/disp_part/default.html, Accessed 9 Dec. 2020.
“Social Distancing.†CDC, U.S. Department of Health & Human Services, 17 Nov. 2020, https://www.cdc.gov/coronavirus/2019-ncov/prevent-getting-sick/social-distancing.html, Accessed 9 Dec. 2020.
Matrajt, Laura, and Tiffany Leung. “Evaluating the Effectiveness of Social Distancing Interventions to Delay or Flatten the Epidemic Curve of Coronavirus Disease.†CDC, U.S. Department of Health & Human Services, 21 Apr. 2020, https://wwwnc.cdc.gov/eid/article/26/8/20-1093_article#:~:text=Proportion%20of%20coronavirus%20disease%20cases,%E2%80%93I)...., Accessed 9 Dec. 2020.
Lake, Rebecca. “Grocery Shopping Statistics: 23 Fun Size Facts to Know.†CreditDonkey, 2 July 2020, www.creditdonkey.com/grocery-shopping-statistics.html.
Smileyforme1235, et al. “Cashiers, about How Many People Do You Check out per Day? [Curiosity].†5 Dec. 2016, www.reddit.com/r/walmart/comments/5gpzd3/cashiers_about_how_many_people_do_you_check_out/. Accessed 9 Dec. 2020.
Team Members:
Caroline Teng
Brandon Tso
Jayden Hogue
David Nguyen-Ho
Krystal Lapahie
Sponsoring Teacher: Geizi Dejka