Does a Refrigerator Make a Good Faraday Cage?

The other week, the New York Times reported that NSA whistleblower Edward Snowden was understandably cautious about planning his departure from Hong Kong to Russia (emphasis mine):

“It was a cloak-and-dagger affair. Mr. Snowden wore a cap and sunglasses and insisted that the assembled lawyers hide their cellphones in the refrigerator of the home where he was staying, to block any eavesdropping. Then began a two-hour conversation during which Mr. Snowden was deeply dismayed to learn that he could spend years in prison without access to a computer during litigation over whether he would be granted asylum here or surrendered to the United States.

Wait. What? Why are the cellphones getting chilled? Snowden’s idea, presumably, was that the refrigerator would act as a Faraday cage. As I explained last year when talking about the effectiveness of tin foil helmets, a Faraday cage is an enclosure made up of a conducting material that shields its interior from external electrostatic charges and electromagnetic radiation by distributing them around its exterior and dissipating them. While these enclosures are sometimes actual cages, they come in many forms, and most of us have probably dealt with one type or another. The scan rooms that MRI machines sit in and the shielding on USB cables, for example, both provide protection as Faraday cages. Inside such a cage, signals to and from these lawyers’ cellphones would be blocked, preventing them from being used to surveil the meeting.

In theory, a sturdy metal fridge should make a good Faraday cage. In practice, some fridges don’t really cut a cell phone off from the rest of the world. Make magazine writer Michael Colombo tried it out with his home refrigerator, and was able to make a call to a phone inside of it. He had better results with a metal cocktail shaker.

I put my fridge to the test, too, and got the same result. Calls and data transmissions went right through. I have a glass cocktail shaker, so that's not an option for me if I'm trying to stay hidden. I wondered if there was a decent kitchen Faraday cage available to people like me, or the poor souls who have no cocktail shaker at all.

I lurked on some survivalist message boards for a while (not an activity I can recommend) and learned that a lot of doomsday hobbyists plan on relying on their microwave to protect their electronics if the government/aliens/New World Order tries to mess with them with an electromagnetic pulse. This makes sense, since, unlike a fridge, a microwave oven is actually designed specifically to shield the electromagnetic radiation of microwaves and keep them from getting out of the appliance. If electromagnetic radiation can’t get out, then it shouldn’t be able to get in either.

Sure enough, calls and data sent to my phone while it sat in my old GE microwave never went through. I could see it sitting in there, but there was no ring, no alerts. When I pulled it out, there was no missed call notification, either. So, the next time you need to keep prying eyes and ears away from your phone, your best bet seems to be tossing it in the microwave or a (metal) cocktail shaker. Just don’t forget about it when you heat up some leftovers or make a Manhattan.

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Big Questions
What Do Morticians Do With the Blood They Take Out of Dead Bodies?
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Zoe-Anne Barcellos:

The blood goes down the sink drain, into the sewer system.

I am not a mortician, but I work for a medical examiner/coroner. During an autopsy, most blood is drained from the decedent. This is not on purpose, but a result of gravity. Later a mortician may or may not embalm, depending on the wishes of the family.

Autopsies are done on a table that has a drain at one end; this drain is placed over a sink—a regular sink, with a garbage disposal in it. The blood and bodily fluids just drain down the table, into the sink, and down the drain. This goes into the sewer, like every other sink and toilet, and (usually) goes to a water treatment plant.

You may be thinking that this is biohazardous waste and needs to be treated differently. [If] we can’t put oil, or chemicals (like formalin) down the drains due to regulations, why is blood not treated similarly? I would assume because it is effectively handled by the water treatment plants. If it wasn’t, I am sure the regulations would be changed.

Now any items that are soiled with blood—those cannot be thrown away in the regular trash. Most clothing worn by the decedent is either retained for evidence or released with the decedent to the funeral home—even if they were bloody.

But any gauze, medical tubing, papers, etc. that have blood or bodily fluids on them must be thrown away into a biohazardous trash. These are lined with bright red trash liners, and these are placed in a specially marked box and taped closed. These boxes are stacked up in the garage until they are picked up by a specialty garbage company. I am not sure, but I am pretty sure they are incinerated.

Additionally anything sharp or pointy—like needles, scalpels, etc.—must go into a rigid “sharps” container. When they are 2/3 full we just toss these into one of the biotrash containers.

The biotrash is treated differently, as, if it went to a landfill, then the blood (and therefore the bloodborne pathogens like Hepatitis and HIV) could be exposed to people or animals. Rain could wash it into untreated water systems.

This post originally appeared on Quora. Click here to view.

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Why Does Asparagus Make Your Pee Smell Funny?
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The asparagus has a long and storied history. It was mentioned in the myths and the scholarly writings of ancient Greece, and its cultivation was the subject of a detailed lesson in Cato the Elder's treatise, On Agriculture. But it wasn't until the turn of the 18th century that discussion of the link between asparagus and odorous urine emerged. In 1731, John Arbuthnot, physician to Queen Anne, noted in a book about food that asparagus "affects the urine with a foetid smell ... and therefore have been suspected by some physicians as not friendly to the kidneys." Benjamin Franklin also noticed that eating asparagus "shall give our urine a disagreeable odor."

Since then, there has been debate over what is responsible for the stinky pee phenomenon. Polish chemist and doctor Marceli Nencki identified a compound called methanethiol as the cause in 1891, after a study that involved four men eating about three and a half pounds of asparagus apiece. In 1975, Robert H. White, a chemist at the University of California at San Diego, used gas chromatography to pin down several compounds known as S-methyl thioesters as the culprits. Other researchers have blamed various "sulfur-containing compounds" and, simply, "metabolites."

More recently, a study demonstrated that asparagusic acid taken orally by subjects known to produce stinky asparagus pee produced odorous urine, which contained the same volatile compounds found in their asparagus-induced odorous urine. Other subjects, who normally didn't experience asparagus-induced odorous urine, likewise were spared stinky pee after taking asparagusic acid.

The researchers concluded that asparagusic acid and its derivatives are the precursors of urinary odor (compared, in different scientific papers, to the smell of "rotten cabbage," "boiling cabbage" and "vegetable soup"). The various compounds that contribute to the distinct smell—and were sometimes blamed as the sole cause in the past—are metabolized from asparagusic acid.

Exactly how these compounds are produced as we digest asparagus remains unclear, so let's turn to an equally compelling, but more answerable question:

WHY DOESN'T ASPARAGUS MAKE YOUR PEE SMELL FUNNY?

Remember when I said that some people don't produce stinky asparagus pee? Several studies have shown that only some of us experience stinky pee (ranging from 20 to 40 percent of the subjects taking part in the study, depending on which paper you read), while the majority have never had the pleasure.

For a while, the world was divided into those whose pee stank after eating asparagus and those whose didn't. Then in 1980, a study complicated matters: Subjects whose pee stank sniffed the urine of subjects whose pee didn't. Guess what? The pee stank. It turns out we're not only divided by the ability to produce odorous asparagus pee, but the ability to smell it.

An anosmia—an inability to perceive a smell—keeps certain people from smelling the compounds that make up even the most offensive asparagus pee, and like the stinky pee non-producers, they're in the majority.

Producing and perceiving asparagus pee don't go hand-in-hand, either. The 1980 study found that some people who don't produce stinky pee could detect the rotten cabbage smell in another person's urine. On the flip side, some stink producers aren't able to pick up the scent in their own urine or the urine of others.

Have you got a Big Question you'd like us to answer? If so, let us know by emailing us at bigquestions@mentalfloss.com.

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