Student Volunteers
Three student volunteers are used for this activity, one student positioned at each measurement location. If you have 3 SLMs, each student will have their own SLM. In most cases, Dangerous Decibels educators have only 1 SLM and in this case, the single SLM is passed from one measurement location to the next by the educator.

Be sure to instruct the student volunteers in advance of turning on the blender. Let them know you will start the blender and their job is to read the number of decibels on the SLM and remember it. While the blender is running, the educator should go to each student’s location and also remember the dBA levels in case a student volunteer forgets their number during class discussion. Once the measurements are made, the educator goes back to the first measurement position and turns off the blender.

Then the educator asks the class to guess how many decibels were measured at location #1 and if they think the first measurement location produced a safe or dangerous level? Next, have the student volunteer at location #1 give the reading and it should be the highest reading made.