LUNG VOLUMES LABORATORY ACTIVITY:
Making & Using a Spirometer
Background
The volume of air that your lungs can hold, sets an upper limit on the amount of
oxygen that can be exchanged between your lungs and pulmonary capillaries
during each breathe. Obviously, not all of the air in the lungs is available for gas
exchange during a breath. Lung volume is affected by gender, size, age, and
health. In the following exercise, you will construct a rudimentary device to
measure a variety of important lung volumes, called a spirometer, and in the
process you will learn how such measurements can be important in diagnosing
lung aliments.
Objective
1. You should be familiar with the various measures of lung volume and be able
to suggest manners in which these volumes can be used to monitor health in
individuals.
Materials
clear gallon jug
250 ml beaker
water bath container
masking tape
marking pen
funnel
food coloring
vinyl tubing
clean plastic drinking straw
Procedure
Making A Spirometer
1. Tape a piece of masking tape along the side of the gallon jug from the top to
the bottom.
2. Fill a 250 ml beaker to the 250 ml mark and pour the water into the gallon jug
using the funnel. When complete, make a mark and label the masking tape
for this volume (You may mark on the jug if you have nice handwriting).
3. Fill up the gallon jug in 250 ml increments making sure to continue to mark
and label the masking tape for each volume.
4. If necessary, add a few drops of food coloring so that the water can be seen
more easily.
5. Next, fill the water bath container as seen in the diagram below.
6. After the water bath is prepared, place the gallon jug upside down into the
water bath by holding your hand over the mouth of the jug while transferring it
into the water. Hold the jug upright so that it doesn’t tip over.
7. Cut the vinyl tubing to a length that will allow it to extend from a potential
subject, through the water, and into the gallon jug.
Preparing to Use the Spirometer
1. Find a graph of the variety of lung capacity measurements in your textbook.
Copy and label the graph in the first question, using the following terms (you
will have to reason to figure out the location for some of these terms). Terms
include Residual Volume, Tidal Volume, Inspiratory Reserve Volume,
Expiratory Reserve Volume, Vital Capacity, and Total Lung Capacity.
2. After you have determined the various lung capacities, determine a method
for measuring each using your spirometer. Record your methods in the
second question.
3. Then, determine a manner in which these volumes can be used to determine
the Vital capacity and record your equation in the third question.
Using the Spirometer
1. Finally, using the methods that you have developed, measure the various lung
volumes for each of your group members. Record this data in the table
provided the forth question.
Bibliography
Modified from “Catch Your Breath” lab from the Science Museum of Minnesota
http://www.smm.org/heart/lessons/lesson9.htm
LUNG VOLUMES LABORATORY ACTIVITY:
Making & Using a Spirometer
Name: __________________________
Spirometer Preparation
1. Graph of lung volumes
2. Method for lung volume measurements
Tidal Capacity (TV)
Inspiratory Reserve Volume (IRV)
Expiratory Reserve Volume (ERV)
3. Vital Capacity Calculation
Spirometer Use
3. Data Table
Lung Volumes
TV
IRV
ERV
VC
Group Subjects
1
2
3
Spirometer Analysis & Application
4. Given that the average adult individual has a vital capacity of 4500 ml (females
may range as low as 3000ml while males may range as high as 6500 ml),
how do the measurements of your group members compare?
5. How much air do you inhale into your lungs every minute? Show your work.
6. Based on the values for the partial pressure for oxygen in dry inhaled air and
moist exhaled air in your text and your knowledge of how to calculate partial
pressures, determine the percentage of atmospheric oxygen actually enters
the blood stream. Show your work.
7. Based on the two previous calculations, determine the amount of oxygen that
enters your lungs in a minute. Show your work.
8. How might the lung volume(s) of an athlete differ from an average person?
Why?
9. How might the lung volume(s) of a person suffering from emphysema differ
from an average person? Why?