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iwaldron's picture

Video which Demonstrates Experimental Technique

We have prepared a video to demonstrate the procedure for the first experiment and help your students get more reliable results. The video available at demonstrates how to prepare the bag and breathe into the bag. You will want to view this video and then either demonstrate the procedure for your students or have them watch this video. Helpful advice includes:

  • To begin, the bag should be opened completely and swished through the air to fill it.
  • Make sure to have a tight seal between the bag and the person’s face so no air is leaking in and out of the bag.
  • Maintain a tight seal throughout the entire test interval (3 minutes for developing the procedure for evaluating depth of breathing and 4 minutes for the actual experiment).
  • Each subject should stand while breathing into the bag to make it easier for observers to see the whole bag to evaluate the breathing rate and depth and also to standardize posture for different subjects


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