Hands-on Activity: Polluted Air = Polluted Lungs
Educational Standards :
Pre-Req Knowledge (Return to Contents)
A basic knowledge of lungs and the human respiratory system, as provided in the Biomedical Engineering and the Human Body unit, lesson 4: Breathe In, Breathe Out.
Learning Objectives (Return to Contents)
After this activity, students should be able to:
Materials List (Return to Contents)
For Part 1 - Creating a Model Lung, each group needs:
For Part 1 - Creating a Model Lung, the teacher needs:
For Part 2 – Creating a Face Mask Pollution Filter, each group needs:
For Part 2 - Creating a Face Mask Pollution Filter, for the entire class to share:
Introduction/Motivation (Return to Contents)
Put your hands on your ribcage and take a few deep breaths. Can you feel expansion occurring? When the rib muscles contract, the ribs lift slightly. At the same time, the diaphragm contracts down. This allows for more space in the lungs as the air enters (inhalation). Air travels through the trachea, branches into the bronchi and into the lungs. The opposite occurs during exhalation. To better understand how a system works, engineers often create models. The respiratory system is one such system in which creating a model helps us understand it and figure out what might happen to it if some input to the system changes. Engineers must understand the respiratory process in detail if they are to design machines and medicines to help people whose respiratory systems are not functioning properly.
So what happens when polluted air enters your body? What happens to your lungs? What happens to your diaphragm? How does our respiratory system adapt to polluted air? What is in polluted air? Polluted air may contain many things, including dust, mold spores, pollen, car exhaust toxins, ozone, lead and bacteria. When air pollutants and bacteria in the air enter the body, the respiratory system's functions may become impaired.
Environmental engineers are concerned with how air pollution occurs (both outdoors and indoors), how to mediate it (clean it up), and how to prevent it. Biomedical, electrical and chemical engineers are interested in finding ways to help a person's respiratory system if the system is weakened by disease, air pollution or other factors. They might design an artificial lung or a respiration machine for patients whose lungs are recovering from injury or illness, or are waiting for a transplant. Biomedical and materials engineers also create products that can keep people safe from air pollution before their lungs are affected.
One easy way to protect your respiratory system from harmful air pollutants is a face mask. A variety of face masks are on the market today for use by people with allergies, medical personnel in hospitals, and even bicyclists and pedestrians who travel through heavy traffic areas. Engineers design these masks to filter the air by combining different materials. Materials might include porous foam, activated charcoal, filter paper, absorbent cellulose and gauze. Engineers design different face masks for different situations. Something that works effectively at filtering pollen out of the air may not work as well in filtering carbon monoxide from car exhaust.
What do you think an engineer must consider when designing a face mask filter? (Listen to student suggestions. Write these "design requirements" on the board.) Engineers think about the problem to be solved and translate the needs of the problem into design requirements. These requirements and limitations must be considered when designing a workable solution to a problem. Some things they might consider are that the mask covers both the mouth and nose, it allows the person to normally breathe in and out through the filter, and it captures the particles in the air that the person wants to avoid. Comfort (easy to put on, stays in place, non irritating) and repeated use are also considerations in designing a face mask filter.
Today, we will model the respiratory system lungs and diaphragm, and design a face mask filter that could be worn to prevent air pollution from entering the respiratory system.
Vocabulary/Definitions (Return to Contents)
Procedure (Return to Contents)
Before the Activity
With the Students: Part 1 – Creating a Model Lung
With the Student: Part 2 – Creating a Face Mask Pollution Filter
Guide and encourage students by asking them questions, such as: What should engineers consider when designing this type of filter? (Possible answers: Is it is big enough (so that the mask covers both the mouth and nose)? Does it allow the person to still breathe in and out? Does it have gaps where polluted air might still enter the airway? Does it capture the particles that the person wants to avoid? Is it comfortable to wear? How long does it last? How does the filter fit or attach to the face?) Also refer to the "design requirements" generated and written on the board during the activity introduction.
After students have finished their filter prototypes, have them complete the analysis portion of their worksheets. This includes rating the comfort of the mask, how well it attaches to the face, and how well it performs when wet (spray the filter mask with one mist of water to simulate the humidity that results after a time of breathing through the mask).
Attachments (Return to Contents)
Safety Issues (Return to Contents)
Assessment (Return to Contents)
Worksheet: To review the primary respiratory system components, have students label parts and describe their functions on the Respiratory System Worksheet. After students are finished, have them volunteer to write the parts and functions on a larger diagram to post in the classroom, or on a projected overhead transparency of the worksheet.
Activity Embedded Assessment
Part 1 - Guiding Questions: Ask students the following questions as they are making and using their lung models:
Part 2 - Guiding Questions: Ask students the following questions as they are designing and building the face mask filters:
Sales Pitch! Have student teams pretend to be salespeople who are trying to sell their face mask filters to a manufacturer or a consumer. Have teams create a persuasive poster or flyer, as well as a 10-minute sales pitch of their design for presentation at the next class. Have them incorporate into their sales pitch the components, materials and features of the face mask filter and how it works.
Activity Extensions (Return to Contents)
Have students research indoor and outdoor air pollution health effects and risk factors. What types of air pollution technologies are being designed and improved by engineers? As part of this, have students complete any of the five air pollution technologies activities from TeachEngineering's Pollution Solutions lesson in the Air Pollution unit.
Have students combine the respiratory system model with a circulatory system model. How might an engineer design an artificial lung that hooks into the circulatory system?
Activity Scaling (Return to Contents)
References (Return to Contents)
Every Breath You Take. 7th Grade Lesson Plan. Posted July 13, 2007. Download Clean Air Lesson Plans, Clean Air Campaign, Georgia Learning Connections. Accessed December 16, 2008. (Source of activity before modifications and additions) http://www.cleanaircampaign.com/for_schools/clean_air_lesson_plans/download_clean_air_lesson_plans
ContributorsMalinda Schaefer Zarske, Jay Shah, Denise W. Carlson
Copyright© 2008 by Regents of the University of Colorado.
Supporting Program (Return to Contents)Integrated Teaching and Learning Program, College of Engineering, University of Colorado Boulder
Acknowledgements (Return to Contents)
The contents of this digital library curriculum were developed under a grant from the Fund for the Improvement of Postsecondary Education (FIPSE), U.S. Department of Education and National Science Foundation GK-12 grant no. 0338326. However, these contents do not necessarily represent the policies of the Department of Education or National Science Foundation, and you should not assume endorsement by the federal government.