'World's Factory' Fights Pollution with Drones

This city has 900K factories. Also, a wall of sound, and a life-saving keychain.

Researchers Develop Lifesaving Keychain

Food allergies can turn an ordinary meal into a harrowing ordeal, especially when cross-contamination can send an unsuspecting individual into an allergic reaction. Researchers from Harvard Medical School have created a new magneto-chemical sensor they call the integrated exogenous antigen testing system. In case you didn't notice, it lends itself to the fancy acronym, iEat.

It's a point-of-use detection system, and the prototype is an electronic keychain that can detect peanuts, hazelnuts, wheat, milk, and eggs, all in less than ten minutes – and it sends the analysis to an app on your smartphone.

While the $40 price point is impressive, the sensitivity is incredible. According to the FDA, foods can be labeled "gluten free" if they have less than 20 parts per million (ppm), because that is typically the lowest level that can be reliably detected in foods with "scientifically validated analytical methods. The iEat detected 0.1 ppm for gluten. During tests at restaurants, researchers actually found gluten in salad and egg protein in peer.

The researchers hope to expand the device to test for new compounds, particularly pesticides, but their work thus far could already have a profound impact on the 5-15% of the population that are affected by food allergies.

The Wall of Sound

The wall of sound, also known as the European Space Agency's Large European Acoustic Facility (LEAF), is located in The Netherlands.

Why would the ESA need a wall of sound? To see if satellites will be able withstand the noise that launchers produce when they take off and travel through the atmosphere.

LEAF is capable of producing up to 158.5 decibels. About 154 decibels is the same as standing near multiple jets taking off, and you’re in the 150-range when your shooting a gun or playing with fireworks. 

The wall is 11 m wide, 9 m deep and 16.4 m high and has massive sound horns embedded in it. To make the noise, researchers shoot Nitrogen through the horns.

Steel-reinforced concrete walls contain the noise, and are coated with epoxy resin to reflect noise to produce a uniform sound field within the chamber.

The chamber itself is supported on rubber bearing pads to isolate it from its surroundings. 

If you find yourself in the Netherlands on October 8, 2017, you can actually check it out for yourself during the facility's open house.

Factory Town Uses Drones to Fight Pollution

The Chinese city of Dongguan is known as the "world's factory." It has more than 900,000 factories registered in the city and is responsible for producing a fifth of all smartphones in the world -- and the same percentage of sweaters. In such a town, you can imagine that it isn't logistically feasible to have local inspectors walk shop to shop with their clipboards and tablets in tow.

Last year, as the world's factory worked to curb environmental abuses, it has turned to drones that are outfitted with gas sensors.

According to a report in The Drive, when a strange smell or possible pollutant is reported, inspectors deploy these UAVs to the scene where they hover about 33 feet about the ground for a half hour to try and detect nitrogen dioxide or other volatile organic compounds.

Drones are not new to the inspectors. They previously used aerial photography drones to look for telltale signs of polluters, and until now, two-thirds of all tips were never even investigated. These new drones can do the work of 60 environmental inspectors.

This is Engineering By Design with David Mantey.

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