Activity 1.1

Activity 1.2

Activity 1.3

Particle Counting Form


Developer Bio

Drawing a Sample
Activity 1.1

Student Learning Strategies

This process should be performed first, perhaps even before starting the course. Each company may have its own manual and procedures regarding sample collection. In order to correctly draw a sample, which represents the entire fluid, certain steps should be strictly followed, such as taking the sample midstream and not from the top or bottom of the container.

After this activity, students will be able to:

  1. Draw samples into prepared bottles.
  2. Use sterile techniques to keep other components or particles from contaminating the sample.


  1. Use prepared bottles for drawing the samples.
  2. Rinse your hands and the parts for sampling with isopropyl alcohol.
  3. Place a sampling bucket under the outlet.
  4. Loosen (but not remove) the cap on the sample bottle.
  5. Open the outlet and let one half-gallon into the bucket.
  6. Remove the cap and film.
  7. Place the bottle in the stream and collect about 100 ml of the fluid.
  8. Remove the bottle from the stream and replace the cap with its film.
  9. Close the outlet.

It is very important to dispose of the fluid in the bucket properly.

Assessment Tools

  1. What should be used to clean hands and the sampling parts?
  2. Why do you need to take the sample midstream after a half-gallon is let into the bucket?
  3. Why do you close the outlet after the sample bottle is removed?

Instructor Learning Strategies

Activity level of difficulty: Beginner

Suggested teaching strategies: Students need a copy of these procedures before starting the class to draw their samples before the wet lab day.

Time commitment: Overall, 10 to 15 minutes


  1. prepared bottles for drawing samples
  2. isopropyl alcohol
  3. alcohol dispenser (with filter)
  4. sampling bucket
  5. disposal container

Troubleshooting Tips: The use of sampling bottles without a film in the cap will make it easier to reduce the chance of contamination.

Answers to the Assessment Tools

  1. isopropyl alcohol.
  2. to ensure that we have a good representative sample.
  3. so that the shavings from the equipment and the outlet will not get into the sample.