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Introducing the Coquí – it's a frog and a tool!

by kanarinka | over 1 year ago | 0 | 2

Have you heard of the Coquí? They are sonorous frogs from Puerto Rico, and the subject of an awesome Menudo video from the 1980s.

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The Coquí is a Puerto Rican frog that makes a "CO" and then a "KEE" sound at night

The Coquí frogs (and sort of the Menudo video) were our inspiration for naming the Public Lab Coquí, an easy, do-it-yourself circuit that makes a buzz-buzzing sound when you dip it in water.

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Illustration by Akshaya Sawant

The Coquí circuit measures conductivity, a key water quality parameter. Conductivity is a measure of how "conductive" water is of electricity. If water is very pure H2O then the conductivity will be low because electricity doesn't pass well through water. But if there is a lot of stuff other than water in the water -- like mud, chlorine, or salt -- then water conductivity will be higher. High conductivity is not always a "bad" thing -- lots of rivers carry organic material, for example. And likewise, low conductivity doesn't always correlate to good water quality. Water with a ton of sugar in it would show up as low conductivity because sugar also doesn't conduct electricity very well. That said, water conductivity is a generally interesting indicator for how much "not water" is in your water and can help you ask questions about what that "not water" might be.

The Coquí was developed by Don Blair and Jeff Warren along with the Open Water Project based at the Public Lab. It's designed to be used in educational settings, and it doesn't measure precise values for water conductivity. Rather, it outputs a conductivity measure as a sound. You dip the Coquí's probe into water and it makes a high-pitched sound for higher conductivity and a low-pitched sound for lower conductivity.

Video from Chelsea Tremblay's sensor journalism research note

So while it's not a tool for collecting precise scientific measurements (if you want that you might want to check out the Riffle or some of the data loggers available from KAPtery), the Coquí is a great tool for introducing newcomers to building circuits, water conductivity, and civic science. Here are the benefits:

  1. It's pretty cheap.
  2. Newcomers can build the circuit in less than 1 hour
  3. You can use it in educational modules where learners bring water samples to class and then measure their conductivity together
  4. You can use it to instigate conversations about civic science and water quality in your community

I teach data journalism and I have used the Coquí with my undergraduate journalism students to collect water samples from the community, test their conductivity, and then reflect on the role of journalists in regards to "sensors". Below is a map the students made of water conductivity in the Greater Boston area.

Water conductivity map made from samples the students collected around the Boston area

After running this module several times, I worked with graduate student Akshaya Sawant to create a free, illustrated guide to running a sensor journalism workshop. You can use this to help you get started using the Coquí inside or outside the classroom.

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The Sensor Journalism Guide for Educators uses the Coquí to walk journalists and storytellers through an exercise in sensor journalism.

The Coquí kit is available from the public lab store. If you use it in the classroom or workshops, we want to hear about it! Post your research notes or ask a question and use the tags "Coquí" and "water-quality".

More Resources:

Catherine D'Ignazio is an organizer with Public Lab and an assistant professor of Civic Media and Data Visualization in the Journalism Department at Emerson College. Learn more about her work at

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Introducing Pi Builder

by icarito | over 1 year ago | 9 | 8

The Public Lab Kits Initiative uses Raspberry Pi cameras more and more, and was in need of a workflow to generate customized operating system images for specific needs such as the Microscope and Lego Spectrometer Kits.

In general, while Raspberry Pi mini-computer boards are amazing, there's a significant barrier for many people to use them, which is the installation and configuration of the memory card with useful software -- like camera software, for example!

Plug and play

We wanted to have a way to generate different pre-loaded SD cards, repeatably and reliably, for different uses. And we wanted people to be able to simply insert an SD card, plug in the camera and power, and start using the Raspberry Pi as a camera as quickly as possible.

We also had a desire to build a process whereby the community could participate in the construction of the operating system that we distribute with our kits and also to share recipes and ready-made images for usage in specific scenarios.

The default operating system image is meant to simplify the workflow for kit users, so these well-defined features needed to be set up:

  • A WiFi hotspot with a _captive portal _(like airport WiFi) so you are prompted as soon as you connect
  • A streaming web camera application
  • Ability to run scripts (e.g. Timelapse)
  • A friendly landing page with links to the above

I was contracted for this and so I had to come up with great shoulders to stand on in order to deliver all features! Disclosure: I am also Public Lab's part time Systems Administrator.

Fortunately thanks to the great work of the Hypriot Project, and the Gitlab CI service, we are able to iterate quickly and collaboratively, from an orderly and flexible base.

Please consider this release a Beta to try out


☁️ Download latest combined image


The documentation is included with the combined image. You may also read it online.

We also have a page for Q&A, troubleshooting, and activity guides here.


Adding a new "recipe" is quite easy -- it is possible to fork our repository, make your modifications and open a pull request, which our system will use to generate a new custom image. You can then download a fully built customized image ready to be burnt into your Pi¹.

¹: Tested on Pi Zero W only.

We'll be thrilled to see this repository evolve in alignment with the communities's needs.

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Reply-by-email: a new way to use

by warren | over 1 year ago | 7 | 0

Today we're announcing a new feature you may have noticed over the past few weeks! For a long time, emails about new posts or comments on have been from an address called -- how unfriendly! But it's because, unlike a mailing list, you couldn't just write a reply email. Remember this?image description

Now you can reply by email!

Thanks to amazing work by a number of Google Summer of Code fellows (#soc), but primarily by Naman Gupta, you can now just write back a reply email, as long as you're sending from the same email you're signed up with. (log in and check this here)

(This will work for any email you get from that has a post id in the subject line, like this: Title of the email (#1234) -- that's most of them!)

It's a new feature, so give it a try, and report back if you have any trouble!

Looking ahead

This means that, soon enough, we will be relying more on the website as a forum, rather than on our old Google Groups. To stay in touch with others working on topics you care about, be sure to SUBSCRIBE using the many prompts on the site, for example at the top of any topic page (linked to from your dashboard, or the front of!):

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Lots of changes & activity

You may have noticed a lot of changes on recently -- this has been made possible by a dramatically growing community of software contributors, joining us through our new coding Welcome Page at, as well as through programs like Rails Girls, Outreachy, Google Summer of Code and Google Code-In -- and with support from the DIAL Open Source Center and the Schmidt Foundation's 11th Hour Project.

Hundreds of new people (see the bottom of have started showing up to help fix bugs, implement new features, and help others in turn join in our efforts -- a very Public Lab spirit! And we've made serious efforts to reach out to and welcome members of groups that are under-represented in open source. You can read about our outreach work here. The result is that the collaboration systems we use across this community are getting refined and improved faster than ever!
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Our code contributor community is built on a commitment to mutual benefit -- we can't create good software without welcoming in newcomers, and we are deeply invested in supporting contributors to learn new skills and grow as coders, designers, project leaders, and "cooperators". Unlike many open source communities, much of our capacity is aimed at helping people become proficient coders, and to learn and apply new skills.

But we also seek to change coding culture by recognizing how important communication, mutual support, and affirmative and welcoming tone are. As part of this, we seek to improve ourselves and help contributors learn how to support one another, welcome in a diverse and inclusive community, and build a more positive and equitable society by doing things a little differently.

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Introducing a new Privacy Policy for Public Lab

by warren | over 1 year ago | 2 | 1

At the Public Lab non-profit, we are committed to the ethical and respectful use of personal information. In our work, and to serve our community and those we work with, we need to make use of personal information in a number of ways. We always seek to protect individual privacy while we fulfill our responsibilities and mission, and when these must be balanced, we seek to do so transparently and in good faith.

As part of this commitment, but also as part of our response to the new General Data Protection Regulation in Europe, today we are publishing a privacy policy which will cover all Public Lab websites and handling of personal data.

We've done our best to explain things in plain language, and as thoroughly as possible, even providing new information on IP-address anonymization at a supporting page here:

Most of it affects only those people who sign up and create an account on, attend an event, or otherwise interact actively with Public Lab websites and systems.

Finally, it's been our intent in this document to explain why we handle different kinds of data in order to fulfill our role hosting these spaces and fulfilling the Public Lab mission.

Please give it a look -- thank you!

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Northeast Barnraising 2018: How to Make Disasters Less Disastrous #Barnraising #crisisconvening

by zengirl2 | almost 2 years ago | 3 | 2

This Northeast regional Barnraising was like no other because it started with people exchanging stories of disaster. It was an appropriate ice breaker since the first day was dedicated to crisis convening. I shared my experience of an earthquake that hit while I was at a café in Philadelphia. I remember my inner dialogue went from "possible subway work" to "nearby construction" to the gut instinct that this was an earth shaking event. How much time did I lose arguing with myself? What would I do differently next time? As others shared their encounters questions arose: How many people have experienced natural disasters? What does emergency relief look like? What should it look like?

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It's hard to compare a small earthquake that merely puts people on edge, to a hurricane with flooding that causes loss of homes, jobs, food and electricity. Testimonies from flood survivors, (who I'm now renaming flood wranglers) provided details of rising waters and destruction in so many communities---New Jersey, Texas, Florida, El Salvador and Puerto Rico. I know I was swept by the emotions of sadness, fear and anger hearing about their situations. Yet there were also stories of community leaders, bartering and rebuilding that brought hope. After another day of Barnraising, the stories started to sound similar. In fact, you could have exchanged locations and faces, but the same problems were surfacing.

  • People were not being helped
  • Governments were failing to respond efficiently (or not at all)
  • Communications failed
  • Systems were not in place for food and water

The greatest thing about a Barnraising is that it not only provides a safe place to discuss problems, but it also encourages sharing current solutions while working on new ones. One of the best tools I heard presented was the common bicycle. They can be used for transporting supplies and medical aids, as they are nimble when most roads are jammed or impassible. Bikes are also able to be hacked to become generators to recharge phones--that's something everyone should have in place!image description

One of the sessions that got me most excited was creating a "Communication Checklist". Solid ideas were put on paper about the best ways to communicate during a disaster when electricity fails. Details include using flyers with bold/cultural images to communicate meeting places and times, connecting with community leaders, using libraries as hubs, encouraging face-to-face communication and supplying printouts of resources.image description

Choices of resources are often not controlled by communities, and one session addressed that problem by creating a blueprint for a Rapid RFP (Request for Proposal). It includes a transition/handoff plan, deliverables, timeline and transparent budget. This entire process would help to ensure that a community receives the right help it needs and would also put into place a checks and balances for how the process is working out.

Checks and balances is probably just the shadow of what I encountered on this Barnraising. The most memorable part was hearing quavering voices as truths were shared across all disasters including government mistrust, racism, receiving inappropriate supplies, neglect, hunger, sickness and homelessness. Still these discussions are so fresh in my mind and I'm so thankful for those that were able to stand up in front of the group and be so honest. We need to hear this---the world needs to hear this. So, what can we do to make disasters less disastrous? Here's what I learned so far:

  • Start making connections with your community now to prepare---leaders and resources
  • Despite mistrust, we must work to communicate with government so they become partners
  • Have a plan of action for your household and family members including supplies
  • If disaster strikes a community other than your own, make sure you are invited to help by the community or from a trusted resource of that community. The history of the community is an important consideration and a great example can be found on this post about the situation in Puerto Rico.
  • Money doesn't solve the problem in larger disasters---be ready to barter and share
  • Use the connections made at Barnraising to boost our network and join to help

We cannot escape that all things are interconnected and I know that I'm still learning how to ask for and accept help. For those that attended the Barnraising, please do add in your thoughts on what you learned or what could be helpful in a disaster. I remain in awe of flood wranglers and those serving in disasters.

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The fight to get out of Pascagoula

by stevie | almost 2 years ago | 2 | 4

Pascagoula, Mississippi hosts 12 facilities that report to the federal Toxics Release Inventory, six of which are within a mile-and-a-half radius of the Cherokee Forest Community (2016 Reported toxic release data here). Below is the story of Barbara Weckesser, and her struggle to get out.

Barbara Weckesser:

“Today, I couldn't sit outside for all the noise. We itch all the time. My eyes burn all the time. People who move here get sick. The children who were unhealthy here move away and seem to get better. My husband’s health conditions have gotten worse here. It has been a nightmare. I’m wondering how quick can I get bought out, and get out of here?”

On monitoring

Over the past couple of years we’ve done all we can think of to document our concerns and share them with the “right people.” We got the Mississippi Department of Environmental Quality (MDEQ) to come in and do some testing. They came out three or four times, and each test shows something in those air canisters, even though none of the tests they did were done the way they were supposed to; they didn’t leave them out for the required 24 hours, and they all came back with stuff in them.

A while ago, Mississippi Phosphates agreed to put in a monitor and within three days it showed that there was sulfuric acid in the air, and two or three days after that, again. Then, for 28 days that the monitor read “over.” MDEQ’s response to me was “Oh, it was turned off. That’s why it read over.” It wasn’t off; the monitor was reporting sulfuric acid. We have all that data. But when MS Phosphates went belly up, that monitor went belly up too. (Mississippi Phosphates closed and their former site is now listed on the Federal Priority List as a Superfund site.)

We keep odor logs. I’ve got a book, it’s about 13 or 14 inches thick, and it’s by the date for when we’ve written odor reports. I’ve also paid for tests myself. We’ve done particulate matter monitoring and have gotten elevated levels, and we’ve paid for bucket air sampling as well. Each time it shows something in it, but each time they say it’s not something that’s going to hurt you. But when you look at the cancer rates around here, and the number of people who have passed away from cancer just in the past year and a half, something is causing it.

Most of the tests we’ve done have been for particulate matter because that was the cheaper test to do, but that doesn’t capture the chemicals. We want to target the pollutants coming from Chevron, and the bucket sampling can do that, but it requires that you take the samples and get them in the mail right away. It’s not easy to do. It’s too time- and energy-intensive, and too expensive.

On permits and public pressure

We’ve gotten our test results in a public meeting on record. I wanted to use it as a way to put pressure on the new mayor. He promised he would get us out of this situation. Let’s see if he holds it up.

MDEQ said “hit them on their permits” and made us all go to permit training. I said sure, I’d love to hit them on their permits, but we can’t take them on on account of their permits because MDEQ hasn’t made them follow through to renew them. Why is our government letting these companies operate without permits, without them being renewed? They’re not bringing these renewals up for public comment, and even when they do, we comment and nothing changes.

On next steps

Here we sit, our hands are tied, and they can pretty much do what they want to unless we can find something that we can bring them all in on. And the one thing we can bring them all in on is health. Right now, we’re working on starting up a health survey with Dr. Wilma Subra. We’re also working with an attorney, but the work he would need to do is really expensive. It would be great to have an inexpensive and easy way to prove these chemicals are in the air here. I would also love to have some legal environmental health advice for what else we can do to bring these companies to the table to say, “Yes, we did that. Yes, we will work with this subdivision to get them out.”

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