The 5 Most Common Safety Devices That Can Kill You Violently

5 Some Surgical Equipment Can Catch on Fire (If the Patient Farts on It)

To understand why some patients' asses spontaneously burst into flame on the operating table, you have to understand a few things about the tools surgeons use. You wouldn't think that the doctor would, say, whip out a blowtorch to repair an artery -- after all, you're not a cyborg (yet). But they do have something similar -- electrosurgical equipment, such as diathermy, use electric heat to cauterize blood vessels and prevent blood from spurting across the room. And under the right conditions, that shit can totally start a fire.

For instance, just as every frat boy who has won a fart-lighting contest can tell you, it doesn't take much to ignite methane. Back in 2006, a team of doctors in New Zealand were reminded of this the hard way: A man came in to have his hemorrhoids removed, which is pretty routine as far as ass surgeries go. But while using diathermy to cauterize the offending area, the patient cut the proverbial cheese, which sparked a flash fire in the middle of the operating room. It caused burns to the patient's nether regions, which is why none of this is remotely funny and we are not laughing even as we type this. We are relaying it purely as a cautionary tale.

Besides, it's not like it takes a one-in-a-million fart to create a flaming disaster in the operating theater. In 2002, a woman went to an Auckland, New Zealand, hospital to have herself a son. During the delivery (which was by cesarean section), the doctors' diathermy crossed with their disinfectant -- which is mostly alcohol -- and burst into flames. The mother suffered some burns, but the baby was unharmed (though we're assuming that having been born through a veil of hellfire means his entire life will be one long heavy metal album cover).

Then, in the same damn hospital, in the same damn year, a man went in to have his appendix removed. This beyond-common surgery ended with -- you guessed it -- a spontaneous fire, for the exact same reason. You're probably saying, "Ha! It sounds to me like New Zealand is just a wacky place full of hilarious, bumbling doctors! It's like Scrubs has come to life!" Oh, we only picked that story for butt reasons -- in the USA there are up to 650 surgical fires a year. So, almost twice a day.

4 Fire Hoses Can Turn Into Wild, Untamed Beasts

You know being a firefighter is a dangerous job -- that's why those guys are heroes. But you assume the dangerous part is obvious: the fire, the smoke, the prospect of flaming debris and shit falling on you. What nobody thinks about is how freaking dangerous the water is.

The hoses those guys use are pumping up to 250 gallons a minute with pressures of up to 300 pounds per square inch (we know that's hard to comprehend, just try to imagine a bear jumping onto your chest while wearing high heels). So those hoses not only have to be kept in good condition, they need to be kept in perfect condition. Once a hose's 5.0 GPA gets knocked down to 4.999, they're liable to snap, burst, and betray their masters in ways that can send their asses to the emergency room.

In 2012, for example, firefighters in Dunedin, New Zealand, were conducting training exercises when one of their coiled hoses burst. It quickly uncoiled, flailing wildly like an anaconda on angel dust and making a beeline for senior station officer Lindsay Rae. One of its metal couplings struck Rae in the leg and broke the bone, like it was nothing. In the middle of a fire in Dumbarton, Scotland, a rogue hose burst, uncoiled, and bowled over five goddamned firefighters in one shot. Several of them flew through the air like Bruce Lee had just kicked them in the chest, and about the only reason nobody died was because the hose mercifully chose to sweep the leg instead of the skull.

Those aren't freak accidents -- thousands of firefighters get injured by their hoses a year, and it's no small comfort to any of them that statistically, the blaze was almost certainly started by a surgical fart explosion.

3 Air Bags Can Deploy for No Reason (While You're Driving)

Calling that thing in your steering wheel an "air bag" makes it sound like a soft, fluffy, harmless cushion. But if you stop to think about how quickly the thing has to inflate (that is, in a fraction of a second), you realize that it's really a contained explosion. And we mean literally -- it contains a tiny chemical bomb that detonates on impact, instantly filling the bag with expanding gas.

It's a violent reaction, but you don't need to tell that to any driver who's dealt with one of these things unexpectedly popping up in their face like an overexcited dog, right while they're in the middle of driving down the road. Here:

Hear that pop? That was the truck's air bag going off, despite the fact that there wasn't collision and the truck was going maybe 10 miles an hour. Now imagine that on an actual road and not some mud pit. It happened in 2011, when Lisa Jarrett was driving with her aunt and 5-year-old son in tow. Without warning or provocation, the passenger-side air bag decided it was bored and felt like suddenly punching the passenger, her aunt, in the face. She wasn't injured (though considering the gunshot-like noise, she probably needed a change of pants), but that wasn't the end of the ordeal.

Just minutes later, Jarrett's air bag detonated too, clearly pissed over not being invited to the party. This was a slightly bigger issue since, out of all the people in that car, the driver was the one most required to see shit. They survived by stopping the car immediately and getting the hell out, which would've been a lot harder had they been barreling down the interstate. A post-drive inspection by NBC Chicago uncovered that the car's air bag module was unresponsive, as was its black box. Not that the car company would ever humor such an idea, since they're commonly whipcrack-quick to blame the driver for carelessly triggering the bags somehow. After all, when you run over roadkill, you need to do it the right way.

And this, too, was far from an isolated incident. The exact same thing happened two months later, when the air bags in Paul Noonan's car spontaneously detonated and left him scrambling to not cause an accident that any remaining air bags would probably just ignore. And it seems to happen a hell of a lot more than that, judging by the millions and millions of vehicles recalled over the issue. Nobody knows the exact number of occurrences though, since precious few drivers file a complaint, and nobody keeps track of the statistics anyway. We know how many cookies we eat as a people but not how often something meant to protect us fails to do so.

And speaking of auto safety devices that are just waiting to ambush people ...

2 Car Bumpers Can Become Explosive Missiles When They Get Too Hot

You don't think of a car bumper as high technology. Isn't it just a hunk of metal or plastic meant to take the abuse when you come into the garage too hot and bang into the back wall? But like everything on a modern car, bumpers have some high-tech shit built in it -- specifically, small gas or gel-filled cylinders that are designed to absorb some of the impact of a low-speed collision. That way if you crash at 20 miles an hour, your car won't turn into something out of a crash test dummy seat belt PSA. So what could go wrong?

Fire.

If you, say, put a sealed can of beans in a fire, before long the liquid will boil and the steam will build up inside. A moment later, you'll hear a loud bang, and everyone in the vicinity will be wearing beans. Well, in a fiery accident, those sealed canisters in a bumper can explode, too, sending the bumper flying like a white-hot javelin. You'll see it in this video:

And this one:

Yeah, it sounds like somebody inside the wreck is firing a shotgun at the firefighters. In addition to the videos above, such an explosion occurred in 2005 in Salinas, California. Firefighters were attempting to extinguish a Volvo fire when its shock-absorbing bumper suddenly burst and shot itself 20 feet away from the vehicle. Miraculously, nobody was harmed, and we say miraculously because they actually came within several feet of being goddamn impaled by a 50-pound chunk of molten metal.

See, we've trained our firefighters to approach a car fire from a 45-degree angle -- that way they're not in the way should a bumper go "boom." Except it turns out that lots of times, those hydraulic bursts send the bumpers flying at -- say it with us -- a 45-degree angle. That's what happened in Salinas, as well as both of the above YouTube'd incidents. What's more -- these bumpers fly fast. The Salinas firefighters were standing 10 feet away at most and didn't see a goddamn thing. That's how quickly these things can kill you if you're anywhere near them for more than, oh, a nanosecond.

And for those of you quick to dismiss us because MythBusters slapped a giant BUSTED graphic over their coverage of the story: all they busted was the idea of an exploding bumper shooting 50 feet. Anything closer, though? Confirmed, and scary as shit.

1 Some Fire Sprinklers Are Filled With Flammable Chemicals

You'd assume that the only way a fire sprinkler could go wrong is if it doesn't trigger at all. Otherwise, what could be simpler -- it detects smoke or fire, then shoots out water to douse the flames. So, you can imagine the surprise people feel when they see the sprinklers kick on and act like goddamned ceiling-mounted flamethrowers.

The problem is that, in order to keep pipes from freezing up in the winter, some sprinklers mix glycerin antifreeze with the water. That chemical happens to be flammable. Now, it's not a problem when mixed properly, but it's not hard for the flammable stuff to build up in the pipes if it's done incorrectly. This means highly flammable liquid raining down on already pissed-off flames, and everyone in the vicinity realizing that "fight fire with fire" is actually a terrible safety policy.

And in fact, the chemical downpour doesn't even need an open flame to ignite. In 2001, an overhead heater at Windansea restaurant in Highlands, New Jersey, grew hot enough to trigger the restaurant's sprinkler. The glycerin sprayed all over the heater like Satan's drunken piss and quickly ignited a blaze, the highlight of which (if you can call it that) was a gigantic fireball melting the walls and shooting through the eating part of the restaurant. While nobody died, 19 people were injured.

Then in 2010, it happened again, only this time with actual fire to fuel the flames. Allix Thrall's 3-year-old son, Luke, was playing with matches -- despite having the hand-eye coordination of, well, a toddler, Luke managed to strike a flame and set a small fire. This activated the glycerin-loaded sprinklers, which quickly turned the fire into a gigantic inferno that sent both Luke and Allix to the hospital with second- and third-degree burns. In a 2009 incident, sprinklers actually triggered an explosion powerful enough to blow debris 90 feet away, killing one victim and injuring another.

Finally, in 2010, the National Fire Protection Association banned antifreeze in all new sprinkler systems. Sounds great, except it does nothing for the millions of old, chemical-filled sprinklers still hanging around and waiting to explode like a solar flare. Also, this does nothing for new sprinklers, since the NFPA doesn't actually have power to regulate anything. So either the owners of those systems have to take it upon themselves to get them fixed, or they just pray they never have a fire. If you are one of these people, all we can say is don't let them perform any asshole surgeries there.

Kevin Phelan is an entertainment reporter in New York's Lower Hudson Valley. If enough people follow him on Twitter, he might actually start using the goddamn thing. You can book his face right here.

For more ways the system fails you, check out The 5 Most Popular Safety Laws (That Don't Work). And then check out 22 Insane Laws You Won't Believe Exist in the Modern World.