Name:__________________________________Date:____________Period:_____ Airborne Junk Detector Lab Background: Particulate matter is a term used to describe solid and liquid particles found suspended in the air. The particles have a wide variety of stationary and mobile sources and, therefore, a diverse set of physical and chemical properties. Particulate matter comprises a wide range of substances including road dust, wood smoke, fly ash, diesel soot, and sulfate aerosols. Most of these come from burning fossil fuels for transportation, power generation, and industrial boilers. Particles in the air range in size, from smoke and soot particle that are dark and large enough to see to particles so small an electron microscope is needed. The smaller particles are the greatest health hazard because they can penetrate more deeply into the respiratory tract. Since 1987 the EPA standard for particulate matter is PM-10, which include particle with a diameter of 10 micrometers or less (about 1/7 the width of a human hair).. The major health problems from exposure to PM-10 are trouble with breathing, damage to lung tissue, cancer and early death. Those populations most affected by PM-10 are the very young, the elderly and those with lung disease and asthma. New scientific evident suggest that particle smaller than 2.5micrometers can cause serious health problems. The World Health Organization has done long-term studies that show the risk of premature death has a threshold of annual concentration of PM-2.5 or 10 g/m3. The EPA is reviewing possible changes in the existing PM-10 standard. Purpose: What areas within/around Daniels Middle are prone to accumulate small particulate matter? What is the measured air quality at Daniels Middle? Hypothesis:_____________________________________________________ ______________________________________________________________ ______________________________________________________________ Safety: Materials: 2 standard size (3x5) index cards Small grid (less than standard 4x4 graph paper) graph paper Clear packing tape String Magnifying glasses Ruler Glue Stick 1 Class Control Procedure: 1. Obtain a piece of graph paper smaller than the index cards that will be used in the experiment. 2. Glue the graph paper to one index card, and set aside to dry. 3. On the second card, cut out the center leaving a rectangular border of 1.5 – 2 cm in width. Place pieces of the packing tape over the hole in the second index card. The card will now have one side that is sticky from the tape, and one side that is not adhesive. 4. With the sticky side of the second index card facing upward, place card two over the first card with the graph paper. BE SURE THE STICKY SIDE OF THE TAPE IS FACING AWAY FROM THE GRAPH PAPER. Connect the two cards together by stapling around the border. Attach a piece of string to the top of the “junk detector” for hanging purposes. Be sure to put your name somewhere on the detector. Card 1 Finished Product Card 2 5. Place the “junk detectors” in different locations in/around the school for 2-4 days. Be sure that any outside detectors are protected from rain. 6. After collecting the detectors, use the magnifying glass to attempt to count the number of particles in a predetermined number of grid spaces. 7. Choose 3 random locations around your graph paper and average the number of particles for the 3 measurements. 8. Compare the number of airborne particles from each location and determine a ranking. These data, although rather qualitative during to the particle counting method, should show differences in the relative amounts of airborne particles in/around a school. Results/Observations: Use ranking scale for comparison Control Sketch Experiment Sketch Observations: (Qualitative and Quantitative) Observations: (Qualitative and Quantitative) Ranking Ranking Conclusion: 1. What was the ranking of your location compared to the class control? 2. What do you think are the sources of this air pollution? List the sources: 3. How does air pollution affect your health? 4. How does air pollution affect the environment? 5. What are some ways to prevent air pollution? 6. Do you think your card would look different at a different time of year? Why or why not?
