Vivergy Inventions: Wi-Fi Enabled Outdoor Air Quality Monitor

Air pollution, specifically particulate matter 2.5, can vary significantly over space and time. Although the EPA’s AirNow system is good in the sense that it has highly accurate monitors and releases the data hourly to the public, I was dissatisfied with its coverage in my area, the greater Boston area. There are 5 monitors that provide data to 4.7 million people… not very granular! Furthermore, this data is pretty impersonal- these monitors are not located in publicly visible places, and simply reporting an air quality value for a massive area is not going to make it feel very real to people after considering that air pollution is not in a high enough concentration to be visible here 95% of days.

So, I wanted to bring air pollution data down to a very human level so the average Boston resident could understand its relevance to their lives. My requirements for the monitor were:

1. A technology that was proven accurate in independent testing for a reasonable price
2. Live streaming to the web via Wi-fi for ease of sharing the data
3. Weatherproof down to 0 degrees Fahrenheit, able to withstand the Massachusetts winter
4. Power and internet demands that were easily available in the US
5. Minimal maintenance for ease of use by end-user
6. 100% uptime, no interruptions in service by device.

The following instructions show how I built V1 for approximately $500. I settled on creating a system based around the following 3 technologies:

1. Dylos DC 1100 Pro with PC interface (link)
2. CanaKit Raspberry Pi w/ Wi-Fi (link)
3. Primex P1000 weatherproof case (link)

Other things you will need:

-Reflectix Insulation (link)

-Velcro adhesives (link)

-Zipties

-Incandescent rope lights for heating (link)

-Trendnet Serial to USB cable (link)

-3 Way Wall Outlet Plug Adapter (link)

-Scissors

-Box cutter

 

And it looks like this:

Here are 4 key resources I consulted to make this:

1. Drexel senior design project, outdoor Dylos system (link)
2. WorldAQI Build Your Own Wi-Fi Enabled Dylos Monitor (link)
3. Outdoor Cat Enclosure, heated and insulated for cheap (link)
4. Accuracy testing for Dylos monitor (link1)(link2)(link3)

Live experiment streaming currently at joinvivergy.com/schools

The heating method is needed for proper functionality of the Dylos. In order for the Dylos to read accurately, it needs to be at a temp above 32 degrees Fahrenheit, I aim for 40 degrees to be safe.

Part 1: Connecting Raspberry Pi to Dylos/ Wi-Fi Enabled

1. Set up your Raspberry Pi with Raspbian OS, as provided
2. Connect your Raspberry Pi to the Dylos with the Serial to USB cable.
3. Download the PHP scripts from the WorldAQI project (link) to the Pi and follow included instructions. You are also going to want to set it up so that they run on startup of the Pi, instructions at that link as well. Furthermore, you may want to stream the results to your personal server if you want to manipulate the data yourself. Check line 82 of /dylos.php to change to destination of data.

Finished picture:

 

Part 2: Setting Up the Enclosure

Start by lining your Primex P1000 with insulation, attached with Velcro.

Bare enclosure

Plan for velcro on Primex

And Reflectix Insulation

 

Finished picture with velcro attached (minus second strip of velcro for attaching incandescent lights

 

Part 3: Assembling pieces within enclosure

First, the lighting/heating. Coil the incandescent rope light into a loop that fits on the left side of enclosure, then use a zip tie to hold the form. Use two loops of Velcro to attach to the top, the attach to the two lines of Velcro “hooks” on top.

Diagram

 

Pic

 

Second, everything else. It is going to be a tight fit. You need to add one strip of Velcro “loop” side along the bottom of the Pi, then one strip “loop” side at the top of the Dylos and one at the bottom.

 

Diagram

 

Pic

 

Make sure to remember to turn the Dylos on before putting it in place!

 

Got any questions/comments? Would love to hear ’em. Leave a comment or reach me at kevin (at) joinvivergy (dot) com.

Thanksgiving Pollution Review: It Ain’t Pretty, Folks

The Wednesday before Thanksgiving is one of the biggest travel days of the year. So, we asked, could all of those cars on the road actually change air pollution levels for millions of Americans? We ran this analysis with the Share My Air real-time pollution map at joinvivergy.com/air. We also did a previous analysis of the pollution wave crossing the country in August due to the wildfires on the West Coast

In order to investigate, we looked at 5 cities on the Boston-Washington corridor (Boston, Providence, NYC, Philadelphia, Washington DC). This is where hundreds of thousands of drivers are on the road at a holiday time since all of the cities are within a reasonable driving distance for millions of residents. Then, we looked at 2 urban and 2 suburban air quality monitors at random in each metropolitan area, for a total of 20 monitors. In order to examine the impact of Thanksgiving travel, we looked at the entire holiday week (11/22-11/28), and noted the day with the highest particulate matter 2.5 levels.

And the results were… not great news for human health. Out of the 20 monitors sampled, 80% (16) experienced the most pollution on November 25, the day before Thanksgiving. This day was, on average, 5 ug/m3 higher than the weekly average. In other words, every man, woman and child within the Boston-Washington corridor was exposed to the equivalent of an extra 13 minutes in a sealed car with a smoker on that day (based on this sample).

So what can people do in the future to prevent this? The price of seeing your family for the holiday should not be an extra dose of pollution in 21st-century America. In this case, pollution is caused by personal vehicles, so families will have a lot of control over creating a healthier holiday next year. Two great solutions for this situation are public transit (train or bus) and electric vehicles. Both would allow families to promote clean air with their holiday travels.

Want to review the data yourself? Check out the Share My Air tool at joinvivergy.com/air.

–The Vivergy Team