Wikimedia Commons // Public Domain
Wikimedia Commons // Public Domain

What Happens When You Pull The Emergency Brake On the Subway?

Wikimedia Commons // Public Domain
Wikimedia Commons // Public Domain

If you've ever ridden in a New York City subway car—or pretty much any city's mass transit rail cars—you have probably seen the emergency brake. It's hard to miss, what with its bright red handle and big placard that reads "Emergency Brake." But if you've ever read the emergency instructions that are also posted to the wall, you'll notice repeated caveats for every scenario: "Do Not Pull The Emergency Cord."

So When Should You Pull the Emergency Cord?

According to the MTA's website, "Use the emergency brake cord only when the motion of the subway presents an imminent danger to life and limb." The New York Times, which looked into the matter, relayed transit officials' instructions, who said the only reason you should ever pull the brake is in the event someone gets caught in the door or between train cars and "is about to be dragged to an unenviable fate." Unenviable, indeed.

Pulling the cord during a fire or during a physical attack by one of your fellow straphangers will only hinder emergency workers from getting to your car, which is now stuck underground.

But What Actually Happens When You Pull That Cord?

The emergency brake cord is no joke. It's not like a bus cord that politely dings and tells the conductor, "Stop, please." MTA officials described the process to the Times:

The emergency cord activates compressed-air brakes; an onboard conductor must then notify train traffic controllers, who can contact the Police Department. The braking system must be reset by the train’s crew before the car can start moving again, a process that usually takes 5 to 15 minutes and can delay tens of thousands of passengers traveling on a particular route.

Those compressed-air brakes are pretty powerful, as this video of the MTA testing them will attest:

So yeah, unless someone will be hurt by the motion of the train and that alone, don't pull that cord. A sizable amount of compressed air will hiss out onto the brakes and you won't be going anywhere for a while.

Why Are Mugshots Made Public Before a Suspect is Convicted by the Court?

Jennifer Ellis:

Several reasons.

1. Mugshots can help find people when they have absconded, or warn people when someone is out and dangerous. So there is a good reason to share some mugshots.

2. Our legal system requires openness as per the federal constitution, and I imagine most if not all state constitutions. As such, this sort of information is not considered private and can be shared. Any effort to keep mugshots private would result in lawsuits by the press and lay people. This would be under the First and Sixth Amendments as well as the various Freedom of Information Acts. However, in 2016 a federal court ruled [PDF] that federal mugshots are no longer routinely available under the federal FOIA.

This is partially in recognition of the damage that mugshots can do online. In its opinion, the court noted that “[a] disclosed booking photo casts a long, damaging shadow over the depicted individual.” The court specifically mentions websites that put mugshots online, in its analysis. “In fact, mugshot websites collect and display booking photos from decades-old arrests: BustedMugshots and JustMugshots, to name a couple.” Some states have passed or are looking to pass laws to prevent release of mugshots prior to conviction. New Jersey is one example.

a) As the federal court recognizes, and as we all know, the reality is that if your picture in a mugshot is out there, regardless of whether you were convicted, it can have an unfortunate impact on your life. In the old days, this wasn’t too much of a problem because it really wasn’t easy to find mugshots. Now, with companies allegedly seeking to extort people into paying to get their images off the web, it has become a serious problem. Those companies may get in trouble if it can be proved that they are working in concert, getting paid to take the picture off one site and then putting it on another. But that is rare. In most cases, the picture is just public data to which there is no right of privacy under the law.

b) The underlying purpose of publicity is to avoid the government charging people and abusing the authority to do so. It was believed that the publicity would help protect people. And it does when you have a country that likes to hide what it is up to. But, it also can cause harm in a modern society like ours, where such things end up on the web and can cause permanent damage. Unfortunately, it is a bit of a catch-22. We have the right to know issues and free speech rights smack up against privacy rights and serious damage of reputation for people who have not been convicted of a crime. The law will no doubt continue to shake out over the next few years as it struggles to catch up with the technology.

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

What Happens When You Flush an Airplane Toilet?

For millions of people, summer means an opportunity to hop on a plane and experience new and exciting sights, cultures, and food. It also means getting packed into a giant commercial aircraft and then wondering if you can make it to your next layover without submitting to the anxiety of using the onboard bathroom.

Roughly the size of an apartment pantry, these narrow facilities barely accommodate your outstretched knees; turbulence can make expelling waste a harrowing nightmare. Once you’ve successfully managed to complete the task and flush, what happens next?

Unlike our home toilets, planes can’t rely on water tanks to create passive suction to draw waste from the bowl. In addition to the expense of hauling hundreds of gallons of water, it’s impractical to leave standing water in an environment that shakes its contents like a snow globe. Originally, planes used an electronic pump system that moved waste along with a deodorizing liquid called Anotec. That method worked, but carrying the Anotec was undesirable for the same reasons as storing water: It raised fuel costs and added weight to the aircraft that could have been allocated for passengers. (Not surprisingly, airlines prefer to transport paying customers over blobs of poop.)

Beginning in the 1980s, planes used a pneumatic vacuum to suck liquids and solids down and away from the fixture. Once you hit the flush button, a valve at the bottom of the toilet opens, allowing the vacuum to siphon the contents out. (A nonstick coating similar to Teflon reduces the odds of any residue.) It travels to a storage tank near the back of the plane at high speeds, ready for ground crews to drain it once the airplane lands. The tank is then flushed out using a disinfectant.

If you’re also curious about timing your bathroom visit to avoid people waiting in line while you void, flight attendants say the best time to go is right after the captain turns off the seat belt sign and before drink service begins.

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