# Your car falls off into a river. Your sinking. Whats the best chance at survival? **URL:** \ **Category:** Factual Questions\ **Created:** [August 13, 2004, 6:25am UTC](https://boards.straightdope.com/t/your-car-falls-off-into-a-river-your-sinking-whats-the-best-chance-at-survival/259664 "2004-08-13T06:25:39Z")\ **Posts on this page:** 13\ **Page:** 2
**Author:** ![Peter\_Morris](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/peter_morris/32/359_2.png) [@Peter\_Morris](https://boards.straightdope.com/u/Peter_Morris)\ **Post date:** [August 14, 2004, 3:52pm UTC](https://boards.straightdope.com/t/your-car-falls-off-into-a-river-your-sinking-whats-the-best-chance-at-survival/259664/21 "2004-08-14T15:52:57Z")
Here’s an important safety tip. I learned it while scuba diving, how to make an emergency ascent if your air supply suddenly fails. I’m sure it would apply here. Most important rule: Don’t hold your breath. Seriously. When you’re underwater, the air in your lungs is under pressure. If you surface from 10m down, the air will double in size. From 20m down it will triple in size. Holding your breath = burst lungs. What you should do is exhale slowly and continuously, you wont run out of air, because the air that’s left keeps expanding to replace it. Just say “rrrrrrrrrrrrrrr” all the way up and you should be okay. ---
**Author:** ![Eleusis](https://avatars.discourse-cdn.com/v4/letter/e/f4b2a3/32.png) [@Eleusis](https://boards.straightdope.com/u/Eleusis)\ **Post date:** [August 14, 2004, 10:15pm UTC](https://boards.straightdope.com/t/your-car-falls-off-into-a-river-your-sinking-whats-the-best-chance-at-survival/259664/22 "2004-08-14T22:15:40Z")
> [@Peter Morris](#): > > Don’t hold your breath. I’m no expert here, but I think this advice is only relevant if you’re breathing compressed air at depth using SCUBA. ---
**Author:** ![Martin\_Hyde](https://avatars.discourse-cdn.com/v4/letter/m/47e85d/32.png) [@Martin\_Hyde](https://boards.straightdope.com/u/Martin_Hyde)\ **Post date:** [August 14, 2004, 10:44pm UTC](https://boards.straightdope.com/t/your-car-falls-off-into-a-river-your-sinking-whats-the-best-chance-at-survival/259664/23 "2004-08-14T22:44:44Z")
> [@bouv](#): > > This is harder than you think. Car windows, ESPECIALLY the windshield, are VERY strong, and you are not going to be able to break through with a fire extinguisher, especially if, most likely, you will be pushing it against some water. > > My friend had a car that died, and we parked it in the driveway and decided to have fun bashing the Hell out of it. Well, we happened to have a fire extinguisher that we had to disharge the week before for a small grease fire. Thinking along the same lines as you, we threw it, as hard as we could, against the side windows…nothing. Dozens of VERY HARD throws, from outside and a good distance away to build up enough momentum, and we didn’t have so much as a scratch in the side windows. We knew that the windshield would be impossible, since it has layers of plastic-like material inbetween the safety glass. Your only window you have a chanve to break without a specialty tool designed to do so (like the hammer **Dog80** linked to) is the rear windshield. It’s made out of the same stuff as the side wondows, but not always as think, has defroster wire running through it to make it more fragile, but most importantly is four times the area of a side window, making it MUCH more fragile and prone to breaking. Needless to say, we did manage to break the rear windshield. > > Oh, and we even whacked at the side wondows with a regular hammer and it STILL took forever to break them. It’s like they design the damn thigns not to break, for some strange reason. I’m going to have to call a bit of bullshit. You’re telling me you threw a fire extinguisher as hard as you could at a car’s side windows and they showed NO sign of damage? That’s just impossible for me to believe. I was with a friend once on a road trip, we stop on the side of the road to rest/eat. Well my friend locks her keys in her car, and neither of us had cellphones (this was back before they were popular.) We don’t see really any cars anywhere around, maybe one every 10 minutes comes by, and plus she’s one of the anxious types and doesn’t really want to attract attention from the highway crowd. So she just tells me to break a window. So, thinking this out I work out the best solution. I go for the rear passenger window so that there’s not going to be a lot of glass in the front where we were sitting. I take off my shirt and have her hold it over the window as best she can w/out blocking my way (my logic is this will hopefully stop any glass from flying back at us.) I take off one of my boots, grab it by the heel and using both hands drive it (toe first) into the middle of the window as hard as I can, the side window is the double layer/with plastic goo in the middle type of window, so it doesn’t shatter. But it fractures all over the entire window, pushing on the shirt the entire window itself does a “peeling” action and peels off into the car, I reach in, unlock. If a boot is enough to break a window like that I find it very hard to believe you can be throwing large metal cannisters at a window as hard as you can with no visible marks. Car windows are hard to completely break, but they aren’t hard to damage. Many a time I’ve seen a windshield get a little crack in via a rock thrown at it from a lawnmower or weedeater, and the crack gradually grows until you need to replace the windshield. Windshield have long been made of the double layer glass, but I don’t think side windows have for that long. Back in the 90s I was in a head on collision, it fucked up the left side of the car’s frame and bent it in a way that it shattered all of the windows on the driver’s side of the car. I was covered in glass and it certainly wasn’t the gooey covered glass you often associate with car windows, it was glass like you’d find in many home window panes. And this was a fairly new and fairly expensive car. I think the safety glass is used in fixed windows like the windshield, rear fixed windows, and rear window but for the windows that actually move they just use tempered glass. The windshield was completely fractured but was one big piece of glass with hundreds of cracks in it. ---
**Author:** ![Peter\_Morris](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/peter_morris/32/359_2.png) [@Peter\_Morris](https://boards.straightdope.com/u/Peter_Morris)\ **Post date:** [August 14, 2004, 11:04pm UTC](https://boards.straightdope.com/t/your-car-falls-off-into-a-river-your-sinking-whats-the-best-chance-at-survival/259664/24 "2004-08-14T23:04:36Z")
> [@Eleusis](#): > > I’m no expert here, but I think this advice is only relevant if you’re breathing compressed air at depth using SCUBA. I’m no expert either, but I think the air in the car becomes compressed when you go underwater. ---
**Author:** ![Eleusis](https://avatars.discourse-cdn.com/v4/letter/e/f4b2a3/32.png) [@Eleusis](https://boards.straightdope.com/u/Eleusis)\ **Post date:** [August 14, 2004, 11:06pm UTC](https://boards.straightdope.com/t/your-car-falls-off-into-a-river-your-sinking-whats-the-best-chance-at-survival/259664/25 "2004-08-14T23:06:54Z")
> [@Martin Hyde](#): > > I’m going to have to call a bit of bullshit. > > You’re telling me you threw a fire extinguisher as hard as you could at a car’s side windows and they showed NO sign of damage? Have you never seen _COPS_ when they use their big heavy Maglite® to try to break a car passenger window? I’ve seen them bashing with everything they’ve got on both of sides of a car and it took like 10 hits each before one of them finally broke the window. ---
**Author:** ![Futile\_Gesture](https://avatars.discourse-cdn.com/v4/letter/f/f05b48/32.png) [@Futile\_Gesture](https://boards.straightdope.com/u/Futile_Gesture)\ **Post date:** [August 14, 2004, 11:15pm UTC](https://boards.straightdope.com/t/your-car-falls-off-into-a-river-your-sinking-whats-the-best-chance-at-survival/259664/26 "2004-08-14T23:15:38Z")
> [@Martin Hyde](#): > > I’m going to have to call a bit of bullshit. So you doubt anecdotal evidence. Fair enough. And your conclusion is based on … anecdotal evidence. :rolleyes: You get different types of glass in side windows. Unlike with windscreens, regulations are non-existent. Some have toughed safety glass, most don’t. It also depends on the age and class of the vehicle. So it’s perfectly possible for both tales here to be 100% true and accurate. ---
**Author:** ![pulykamell](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pulykamell/32/3166_2.png) [@pulykamell](https://boards.straightdope.com/u/pulykamell)\ **Post date:** [August 15, 2004, 12:34am UTC](https://boards.straightdope.com/t/your-car-falls-off-into-a-river-your-sinking-whats-the-best-chance-at-survival/259664/27 "2004-08-15T00:34:01Z")
> [@Eats\_Crayons](#): > > Like **pulykamell** said, they encouraged you to wait until the car was submerged because the pressure was so uneven that it’s extremely unlikely that you 'd be able to push the door open. That’s right. I’m not BSing anyone. If anyone has back issues of Car & Driver, I _think_ our article appeared in the March 2001 edition. With the windows open, it takes maybe 10 seconds (IIRC) before your car sinks like a lead weight. You will not be able to open the door if half the door is in the water and half is out. The pressure difference is far too great. Wait for the car to completely fill up and then get the hell out. If you could get out the window before this happens, fine. But you have plenty of time to get out through the door while the car is sinking. Like I said, the door ain’t gonna swing open like above ground, but it will fully open in 3 or 4 seconds. ---
**Author:** ![Dog80](https://avatars.discourse-cdn.com/v4/letter/d/6bbea6/32.png) [@Dog80](https://boards.straightdope.com/u/Dog80)\ **Post date:** [August 15, 2004, 1:10am UTC](https://boards.straightdope.com/t/your-car-falls-off-into-a-river-your-sinking-whats-the-best-chance-at-survival/259664/28 "2004-08-15T01:10:23Z")
I found an interesting article here: [http://www.cbc.ca/consumers/market/files/cars/windshields/](http://www.cbc.ca/consumers/market/files/cars/windshields/) It seems that tempered glass shatters far more easily than laminated glass. But having laminated instead of tempered side-windows would make it much harder to break it in case you end up sinking in water :dubious: ---
**Author:** ![GusNSpot](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gusnspot/32/436_2.png) [@GusNSpot](https://boards.straightdope.com/u/GusNSpot)\ **Post date:** [August 15, 2004, 5:26pm UTC](https://boards.straightdope.com/t/your-car-falls-off-into-a-river-your-sinking-whats-the-best-chance-at-survival/259664/29 "2004-08-15T17:26:18Z")
… Think about the shape of each. Cars side windows are different, in size, in curve, etc… Breaking from outside and inside will be different too. No set answer. But one of those spring loaded window breakers. Driving carefull works best I’ve found… YMMV ---
**Author:** ![olefin](https://avatars.discourse-cdn.com/v4/letter/o/d78d45/32.png) [@olefin](https://boards.straightdope.com/u/olefin)\ **Post date:** [August 15, 2004, 8:35pm UTC](https://boards.straightdope.com/t/your-car-falls-off-into-a-river-your-sinking-whats-the-best-chance-at-survival/259664/30 "2004-08-15T20:35:51Z")
After reading all the post, I will mention what happen here. A few years ago a “Duck”, ( DUKW, amphibious vehicle) a tourist ride with 20 on board sank shortly after entering the water. 13 people lost their life. Only 7 got out of the Duck and not until it hit the 60 foot bottom of the lake. A Duck doesn’t have glass windows… they are wide open with a canvas roof! I’m sure the Duck sank much faster than a car but it just points out how fast something like that can happen and a person is taken off guard. ---
**Author:** ![hyjyljyj](https://avatars.discourse-cdn.com/v4/letter/h/0ea827/32.png) [@hyjyljyj](https://boards.straightdope.com/u/hyjyljyj)\ **Post date:** [August 16, 2004, 1:59am UTC](https://boards.straightdope.com/t/your-car-falls-off-into-a-river-your-sinking-whats-the-best-chance-at-survival/259664/31 "2004-08-16T01:59:50Z")
My wife likes to drive along with the doors locked for safety, to prevent denizens of the city from intruding into the vehicle at stop lights. I hate doing this, for the obvious reason that if we were to take a d®ive into the drink (we live in coastal Florida, lakes and canals are everywhere), the electric locks could fail along with the electric windows, and we’d be doomed to trying the difficult glass-breaking maneuver. We drive Mercedes and Volvo, the sturdiest cars on the road with probably the toughest safety glass in the business, I’m guessing. So I like driving with the doors unlocked for safety. Who’s right? ---
**Author:** ![Dog80](https://avatars.discourse-cdn.com/v4/letter/d/6bbea6/32.png) [@Dog80](https://boards.straightdope.com/u/Dog80)\ **Post date:** [August 16, 2004, 2:18am UTC](https://boards.straightdope.com/t/your-car-falls-off-into-a-river-your-sinking-whats-the-best-chance-at-survival/259664/32 "2004-08-16T02:18:33Z")
Depends on the type of locks you have. The locks in my car are electro-mechanical. You can either operate them from an electric swich on the armrest, or use the mechanical switch on the door. Even if the battery has died, you can still use the mechanical switches. ---
**Author:** ![olefin](https://avatars.discourse-cdn.com/v4/letter/o/d78d45/32.png) [@olefin](https://boards.straightdope.com/u/olefin)\ **Post date:** [August 16, 2004, 4:47pm UTC](https://boards.straightdope.com/t/your-car-falls-off-into-a-river-your-sinking-whats-the-best-chance-at-survival/259664/33 "2004-08-16T16:47:26Z")
> [@hyjyljyj](#): > > So I like driving with the doors unlocked for safety. Who’s right? In Florida, I think your wife is right! 😉 [Previous page](https://boards.straightdope.com/t/your-car-falls-off-into-a-river-your-sinking-whats-the-best-chance-at-survival/259664.md?page=1)