Public Lab Research note

Week 2: recap from Oil Testing Kit Beta Program: Assembly and Calibration

by warren | October 07, 2015 18:09 07 Oct 18:09 | #12280 | #12280

Hi, all - welcome to the Week 2 recap; we just wrapped up the weekly chat and some folks are making great progress (thanks for the above image by @Cindy_ExCites!). Thanks to everyone who showed, and for the great posts we've seen in the past week. Remember to stay up to date by reading the Oil Testing Kit blog:


Lots of folks have started or even completed assembly. We discussed if anyone had a "hardest part" or most difficult step; @tofu mentioned that he had to cut the "shelf" for the laser -- and will post later in the day. @Cindy_ExCites also described making relief cuts in the triangular holes for the shelf.


A quick update -- there's an extra piece in your kits, shaped kind of like a space invader, which was added at the end. It's to cover your chamber to reduce ambient light and to protect your eyes, and was added last minute; instructions for it are here:

@Cindy_ExCites posted a very thorough note on assembly with lots of suggestions and input:


If you haven't gotten to calibration yet, you can use the old procedure, which is tried-and-true, or the new procedure, which is potentially higher precision, but still just a prototype.

So for those who've calibrated, was there any confusion about calibration, or any suggested improvements to the instructions?

@tofu has calibrated, and his data is here: - it looks good, although a little low-resolution. What kind of light bulb did you use?

Has anyone tried the new calibration system?

So I wanted to highlight this kind of intense discussion going on in the post I put up on the new calibration procedure:

Chris has been working to help make the procedure more precise; you won't have to do anything different, but hopefully in the next couple days it'll be really really improved. One interesting point is that Chris is doubting the Wikipedia record of known peaks from a fluorescent lamp:

There's some excellent empiricism and skepticism going on :-) and basically, it's been a good opportunity to attempt to link our data to other sources, such as an Ocean Optics device on wikipedia, and the NIST database by the US gov't.

Also, one member, Bill, couldn't make the chat, but said it was all right for me to pass on his update; he may post his own in more depth later in the day:

I have all of the materials I need, mineral oil, isopropyl alcohol ("solvents" easily obtained at the local pharmacy), glass cuvettes, quartz cuvettes, and your cuvettes, to start generating data. My approach will be to run one sample at a time in triplicate with both solvents and all three cuvettes. In addition I'll also run a spectra of each sample using an old analog scanning fluorometer at the same wavelengths as your spectrometer/fluorometer. If you have any additional suggestions please let me know I'll try to include them as well.

I also wanted to point out @liz's post on oil pollution testing at the New York State DEC: -- a process we should look forward to trying to connect with, and maybe do co-testing to compare our results. @liz - what exactly were the tests they do? Fingerprinting? What kinds of evidence have they taken action on?

Next meeting

The next meeting will be one week from today, 1pm ET as usual -- for those of you a bit behind, please try to catch up so we can get to sample preparation, which will be a bit more involved!

Thanks, all! Below is the transcript from the chat. See you next week!

Chat transcript


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