This activity simulates the monitoring of a gas refinery flare with a Do-It-Yourself spectrometer indoors by substituting a candle for the flare.

• Time and participants: The activity should take approximately 1 hour and is suitable for a group of 4, or multiple groups of 4. 1 hour longer if you need to assemble the spectrometer.
• Related research: http://publiclab.org/tag/flare
• You'll need: a DIY spectrometer, a candle, a tripod and zip ties, salt, a small spray bottle, and a fluorescent light (the ceiling lights may suffice)

Public Lab community members using a spectrometer to monitor a real gas refinery flare in Chalmette, Louisiana Read more

Preparation

Setup: Be sure you have internet access, or you may use just a webcam program and upload your data later. Fill the spray bottle with very salty water and confirm that you can "mist" the water over the flame without putting it out. A bunsen burner can be substituted for the candle.

Which spectrometer? All of the different versions of the Public Lab spectrometer can be used for this activity. The Desktop Kit can be plugged into a laptop and the spectra graphed in real time, which can be nice for using with a projector, and for viewing the wavelengths in a quantitative way -- but works best with an internet connection, using the https://spectralworkbench.org software. The smartphone version (to be released soon) and the foldable mini spectrometer can be used with a webcam, iPhone, or Android phone, the latter two either with the native camera app or at https://spectralworkbench.org.

Calibration: If you have limited time, you may calibrate the spectrometer ahead of time. Also decide if you'd like the students to build their own -- perhaps the foldable paper versions, which they can take home. Calibration can be a nice way to explore the emission spectra of mercury in fluorescent lamps, as well.

The activity

1. Set up the candle across the room on a table, light it, and turn off the lights. (see diagram in main image)
2. Calibrate the spectrometer. If need be, this can be done ahead of time.
3. From the other end of the room, have the students plug in the spectrometer and point it at the flame. This will take some time, as aiming the device may be difficult. (If you are using a Desktop Spectrometry Kit the camera may not be lined up well to point straight out of the device -- it may be biased upwards or downwards)
4. Once the flickering candle is lined up and you can see its spectrum, save an image or spectrum (depending on which device you're using).
5. Now, mist some salt water over the flame. Observe how the flame turns bright yellow/orange, as in the image above.

A diagram of the setup if it were actually observing a gas refinery flare. Read more

Background

Conclusions