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This is all very good PR.... BUT. The critical safety concern with the Tesla is....... You guessed it. The high voltage system. It can kill you or a first resp

by abalone 13y ago

This is all very good PR.... BUT. The critical safety concern with the Tesla is....... You guessed it. The high voltage system. It can kill you or a first responder with a touch. It's not just about batteries catching fire, although that's gotten a lot of press lately. A chief concern during a Tesla accident is the exposure of high voltage components. It's a big concern for first responders. Read it from the horse's mouth, the Tesla Emergency Response Guide. Page 16 highlights the "no cut" zones of the car. It's practically the entire length of the car. http://www.teslamotors.com/sites/default/files/downloads/20130214_ModelS_Emergency_Response_Guide.pdf http://www.teslamotors.com/sites/default/files/downloads/201... There was a video they put out as well that details the steps first responders need to take to cut someone out of a car. It's HELLA COMPLICATED and in very close proximity to dangerous high voltage components. And yes, gas cars can explode, etc. I don't mean this as fuel for the gas vs. electric debate (no pun intended). I hope very much the industry can improve electrical safety over time. All I'm saying is, never trust Elon Musk PR to tell you the whole picture.

sitharus 13y ago
> All I'm saying is, never trust Elon Musk PR to tell you the whole picture. Never trust anyone's PR to give you the whole picture! Though as a counterpoint, I've seen cars with the roof cut off to extract people, but never the side doors or the floor cut open. I don't think they'd cut the floor since it's quite thick and has all sorts of wires and pipes anyway.
- abalone 13y ago
  You've never seen doors cut off? You must not have seen much then.. happens all the time. Google jaws of life. BTW here is the Tesla first responder training video that shows how to cut off a door(!) and move the dash without electrocuting yourself. http://www.youtube.com/watch?v=ntK3rvVl2Qw http://www.youtube.com/watch?v=ntK3rvVl2Qw It's a pretty cool video, I expect most people on this thread would enjoy watching it. I sure did.. although I'm not sure I'd want to be stuck bleeding in a Tesla while they figure it out. Also a little concerned about a short happening during an accident and electrifying passengers.. would like to know more about the risks there.
- JshWright 13y ago
  Firefighter here... The major thing that concerns me about the Model S is the placement of the DC-DC converter in the front right wheel well. There's a common maneuver called a 'dash lift' where you make a couple relief cuts and then lift the dash using a hydraulic ram. Properly place, those cuts are dangerously close to that high voltage system. Explanation of relief cut placement: http://advancedextrication.com/2011/12/closer-dash-lift-part-2-relief-cuts/ http://advancedextrication.com/2011/12/closer-dash-lift-part... EDIT: The video abalone posted has a great walk-through on rolling the dash of a Model S. http://www.youtube.com/watch?feature=player_detailpage&v=ntK3rvVl2Qw&t=1642 http://www.youtube.com/watch?feature=player_detailpage&v=ntK... Another issue is the seat belt pretensioner, which would complicated a 'side blitz' door removal (where both doors are removed as a unit), but that's a pretty standard place for the pretensioner, so it's something we're used to working around.
  - nzealand 13y ago
    Looks challenging. How does that compare with a Prius?
    - JshWright 13y ago
      A Prius is a lot simpler. All the electric components are well away from all the 'usual' cut locations. Obviously all the normal concerns apply (air bags, pretentioners, etc), but from an extrication perspective, they're pretty straightforward. The one issue common to all EVs (hybrid or plugin) is that the can silently deliver power to the wheels. With a 'normal' car, you can hear the engine running. With an EV, it can be harder to tell if it's on or not. One of the first things we do it secure the keys, but with keyless ignition, the key may be trapped in the drivers pocket. That means the big round 'On' button just needs to be bumped by someone for the car to power up. That's why it's critical that we're able to disable the electrical systems of the car, to prevent it from starting up unexpectedly.
agumonkey 13y ago
About that, do cars attempt to shut down engines, fuel intake and electric pathways when detecting a collision ? I remember Liquid Gas vehicles having an emergency outlet to avoid fire/explosions. In Tesla's case that would be cutting the battery off the circuit and maybe putting it into a 'fast drain' mode ..
- MichaelApproved 13y ago
  Fast draining those batteries would likely cause an enormous amount of heat.
  - dredmorbius 13y ago
    This. Batteries have internal resistance. They're generally rated for a certain level of drain (amperage), which, if exceeded, will go over the thermal limits for the battery. In the case of a Tesla, you'd risk being fried (current) _and_ roasted (heat) at the same time. Better simply to keep the energy contained.
- abalone 13y ago
  You can't just "shut down" electric pathways. Not exactly. There is a manual cut that first responders need to make to sever the high voltage circuit before they can work on the car. However there's still capacitors, converters and the battery itself that remain dangerous especially if they've been compromised. As for "fast draining" the battery, where would the power drain to? That's exactly the problem.. NOT giving the power a path to go when you're working on the car. This is not much of an issue with most cars because the electrical systems are low voltage (12V car battery). With Tesla it's enough to cause major injury or death with one touch if you complete the circuit. Watch the video, it explains all this. http://www.youtube.com/watch?v=ntK3rvVl2Qw http://www.youtube.com/watch?v=ntK3rvVl2Qw
  - agumonkey 13y ago
    And I guess it's unrealistic to think of a special draining device to be brought on crash sites to exhaust the car battery. All in all, are electric vehicles more 'instable' energy wise when crashed, compared to petroleum based one ? or is it different flavours of similarly sh*tty situations ?
justin66 13y ago
> I hope very much the industry can improve electrical safety over time. With regard to the electrical aspects, isn't the safety record on these cars perfect or close to perfect up until this date? That means it's only going to get worse. That does not mean electrical cars are unsafe, it just means there isn't much of a record yet. My expectation is that there will over time be a small number of electricity-related accidents involving first responders and passengers and that they will be enough to fuel concern trolls until the end of time. That the electrical problems will be so enormous that they dwarf the massive safety gains from better passenger protection of the sort NHTSA is interested in (and frankly, anyone who is about to get hit by an oncoming SUV is interested in) seems awfully counterintuitive.
- abalone 13y ago
  Wish I had your crystal ball. With improvement, I was referring to the complexity of cutting someone out of a Tesla and all the no-cut zones that could electrocute passengers, emergency responders, even guys towing wrecks. You're right, there is no real safety record yet.
  - lutusp 13y ago
    > With improvement, I was referring to the complexity of cutting someone out of a Tesla and all the no-cut zones that could electrocute passengers, emergency responders, even guys towing wrecks. As an electrical engineer with spacecraft experience, I can say that a car like the Model S isn't likely to electrocute anyone. While extracting someone from a wreck, emergency workers use tools like the "jaws of life", strong metal pliers meant to quickly snip a car's body apart. When a tool like this cuts into an electric car, if it should slice through a power cable, in most cases the tool would short the cable to the car's chassis, thus grounding it and tripping the safety links that are integral to the battery pack. This means the car will become inoperative, but it doesn't mean anyone will get electrocuted. I think the above will be the outcome in the vast majority of cases. Compare this to the plight of someone sitting in a wrecked gasoline-fueled car.
    - abalone 13y ago
triplepoint217 13y ago
Does anyone know what the actual voltages are? Just because it is high relative to the usual 12V of cars does not mean it is terrifically fatal. An anecdote to give you a picture of things: Electric arc welders operate at around 60V with a very large amount of current. However the electricity is not particularly the dangerous thing about them, it is the 9000F arc you are making and the molten steel. So to demonstrate that we shouldn't freak out about the electric danger and worry more about the heat, my instructor had someone touch the business end with one hand and the ground electrode with the other. Bit of a tingle but certainly didn't stop their heart or anything. Welders are kept at low voltage for this reason. I assume that it must be somewhat dangerous because of the responder guides warning, but I would want to know the actual voltage before drawing conclusions. If the voltage is 112 or less (or even 220 or less), it should be possible to be pretty safe with some fairly manageable precautions.
- dmethvin 13y ago
  These are very high voltages. The Tesla is 375 volts and the Prius is 275 volts.
  - el_zorro 13y ago
    Technically, that puts it well into the 'low-voltage' classification; generally, 1000 V is the threshold for 'high-voltage'.
    - kgermino 13y ago
      > generally, 1000 V is the threshold for 'high-voltage' DCV? Not an expert, but my understanding was ~1000V for AC, but much lower for DC
    - TorKlingberg 13y ago
      The definition depends on the context. When discussing risk of electrical shock, below 50V is usually considered low voltage (and safe).
VLM 13y ago
Recycling the same astroturfing from the Prius a decade ago. Boring. Try something new, or people remembering last time around are going to LOL not get scared as intended.
- JshWright 13y ago
  While it's true these concerns are probably overblown in the eyes of the public (it's not something they need to worry about). It's absolutely not 'astroturfing' from my perspective (as someone who may need to cut one of these up some day). I very much appreciate the amount of effort Tesla has put into producing training materials for working with their vehicles.
bborud 13y ago
Good thing regular cars don't contain high voltage components or volatile, flamable fluids that can cause intense fires and even explosions...
- stcredzero 13y ago
  Car explosions have been thoroughly busted by Mythbusters. They are as busted as "Enhance!" Car fires are very real and nasty, though.
- sliverstorm 13y ago
  High voltage? Do you mean the 12V battery that can't shock you, or the spark ignition that won't do much more than startle you? I've had numerous sparks jump from distributors and plug wires through my hand. They just make your hand numb/tingly. If the jump went in your left hand and out your right, there might be some cardiovascular risks, but that's nothing compared to the risks of 400V @ god knows how many amps.

by abalone 13y ago

sitharus 13y ago

> All I'm saying is, never trust Elon Musk PR to tell you the whole picture. Never trust anyone's PR to give you the whole picture! Though as a counterpoint, I've seen cars with the roof cut off to extract people, but never the side doors or the floor cut open. I don't think they'd cut the floor since it's quite thick and has all sorts of wires and pipes anyway.

abalone 13y ago
You've never seen doors cut off? You must not have seen much then.. happens all the time. Google jaws of life. BTW here is the Tesla first responder training video that shows how to cut off a door(!) and move the dash without electrocuting yourself. http://www.youtube.com/watch?v=ntK3rvVl2Qw http://www.youtube.com/watch?v=ntK3rvVl2Qw It's a pretty cool video, I expect most people on this thread would enjoy watching it. I sure did.. although I'm not sure I'd want to be stuck bleeding in a Tesla while they figure it out. Also a little concerned about a short happening during an accident and electrifying passengers.. would like to know more about the risks there.
JshWright 13y ago
Firefighter here... The major thing that concerns me about the Model S is the placement of the DC-DC converter in the front right wheel well. There's a common maneuver called a 'dash lift' where you make a couple relief cuts and then lift the dash using a hydraulic ram. Properly place, those cuts are dangerously close to that high voltage system. Explanation of relief cut placement: http://advancedextrication.com/2011/12/closer-dash-lift-part-2-relief-cuts/ http://advancedextrication.com/2011/12/closer-dash-lift-part... EDIT: The video abalone posted has a great walk-through on rolling the dash of a Model S. http://www.youtube.com/watch?feature=player_detailpage&v=ntK3rvVl2Qw&t=1642 http://www.youtube.com/watch?feature=player_detailpage&v=ntK... Another issue is the seat belt pretensioner, which would complicated a 'side blitz' door removal (where both doors are removed as a unit), but that's a pretty standard place for the pretensioner, so it's something we're used to working around.
- nzealand 13y ago
  Looks challenging. How does that compare with a Prius?
  - JshWright 13y ago
    A Prius is a lot simpler. All the electric components are well away from all the 'usual' cut locations. Obviously all the normal concerns apply (air bags, pretentioners, etc), but from an extrication perspective, they're pretty straightforward. The one issue common to all EVs (hybrid or plugin) is that the can silently deliver power to the wheels. With a 'normal' car, you can hear the engine running. With an EV, it can be harder to tell if it's on or not. One of the first things we do it secure the keys, but with keyless ignition, the key may be trapped in the drivers pocket. That means the big round 'On' button just needs to be bumped by someone for the car to power up. That's why it's critical that we're able to disable the electrical systems of the car, to prevent it from starting up unexpectedly.

agumonkey 13y ago

About that, do cars attempt to shut down engines, fuel intake and electric pathways when detecting a collision ? I remember Liquid Gas vehicles having an emergency outlet to avoid fire/explosions. In Tesla's case that would be cutting the battery off the circuit and maybe putting it into a 'fast drain' mode ..

MichaelApproved 13y ago
Fast draining those batteries would likely cause an enormous amount of heat.
- dredmorbius 13y ago
  This. Batteries have internal resistance. They're generally rated for a certain level of drain (amperage), which, if exceeded, will go over the thermal limits for the battery. In the case of a Tesla, you'd risk being fried (current) _and_ roasted (heat) at the same time. Better simply to keep the energy contained.
abalone 13y ago
You can't just "shut down" electric pathways. Not exactly. There is a manual cut that first responders need to make to sever the high voltage circuit before they can work on the car. However there's still capacitors, converters and the battery itself that remain dangerous especially if they've been compromised. As for "fast draining" the battery, where would the power drain to? That's exactly the problem.. NOT giving the power a path to go when you're working on the car. This is not much of an issue with most cars because the electrical systems are low voltage (12V car battery). With Tesla it's enough to cause major injury or death with one touch if you complete the circuit. Watch the video, it explains all this. http://www.youtube.com/watch?v=ntK3rvVl2Qw http://www.youtube.com/watch?v=ntK3rvVl2Qw
- agumonkey 13y ago
  And I guess it's unrealistic to think of a special draining device to be brought on crash sites to exhaust the car battery. All in all, are electric vehicles more 'instable' energy wise when crashed, compared to petroleum based one ? or is it different flavours of similarly sh*tty situations ?

justin66 13y ago

> I hope very much the industry can improve electrical safety over time. With regard to the electrical aspects, isn't the safety record on these cars perfect or close to perfect up until this date? That means it's only going to get worse. That does not mean electrical cars are unsafe, it just means there isn't much of a record yet. My expectation is that there will over time be a small number of electricity-related accidents involving first responders and passengers and that they will be enough to fuel concern trolls until the end of time. That the electrical problems will be so enormous that they dwarf the massive safety gains from better passenger protection of the sort NHTSA is interested in (and frankly, anyone who is about to get hit by an oncoming SUV is interested in) seems awfully counterintuitive.

abalone 13y ago
Wish I had your crystal ball. With improvement, I was referring to the complexity of cutting someone out of a Tesla and all the no-cut zones that could electrocute passengers, emergency responders, even guys towing wrecks. You're right, there is no real safety record yet.
- lutusp 13y ago
  > With improvement, I was referring to the complexity of cutting someone out of a Tesla and all the no-cut zones that could electrocute passengers, emergency responders, even guys towing wrecks. As an electrical engineer with spacecraft experience, I can say that a car like the Model S isn't likely to electrocute anyone. While extracting someone from a wreck, emergency workers use tools like the "jaws of life", strong metal pliers meant to quickly snip a car's body apart. When a tool like this cuts into an electric car, if it should slice through a power cable, in most cases the tool would short the cable to the car's chassis, thus grounding it and tripping the safety links that are integral to the battery pack. This means the car will become inoperative, but it doesn't mean anyone will get electrocuted. I think the above will be the outcome in the vast majority of cases. Compare this to the plight of someone sitting in a wrecked gasoline-fueled car.
  - abalone 13y ago

triplepoint217 13y ago

Does anyone know what the actual voltages are? Just because it is high relative to the usual 12V of cars does not mean it is terrifically fatal. An anecdote to give you a picture of things: Electric arc welders operate at around 60V with a very large amount of current. However the electricity is not particularly the dangerous thing about them, it is the 9000F arc you are making and the molten steel. So to demonstrate that we shouldn't freak out about the electric danger and worry more about the heat, my instructor had someone touch the business end with one hand and the ground electrode with the other. Bit of a tingle but certainly didn't stop their heart or anything. Welders are kept at low voltage for this reason. I assume that it must be somewhat dangerous because of the responder guides warning, but I would want to know the actual voltage before drawing conclusions. If the voltage is 112 or less (or even 220 or less), it should be possible to be pretty safe with some fairly manageable precautions.

dmethvin 13y ago
These are very high voltages. The Tesla is 375 volts and the Prius is 275 volts.
- el_zorro 13y ago
  Technically, that puts it well into the 'low-voltage' classification; generally, 1000 V is the threshold for 'high-voltage'.
  - kgermino 13y ago
    > generally, 1000 V is the threshold for 'high-voltage' DCV? Not an expert, but my understanding was ~1000V for AC, but much lower for DC
  - TorKlingberg 13y ago
    The definition depends on the context. When discussing risk of electrical shock, below 50V is usually considered low voltage (and safe).

VLM 13y ago

Recycling the same astroturfing from the Prius a decade ago. Boring. Try something new, or people remembering last time around are going to LOL not get scared as intended.

JshWright 13y ago
While it's true these concerns are probably overblown in the eyes of the public (it's not something they need to worry about). It's absolutely not 'astroturfing' from my perspective (as someone who may need to cut one of these up some day). I very much appreciate the amount of effort Tesla has put into producing training materials for working with their vehicles.

bborud 13y ago

Good thing regular cars don't contain high voltage components or volatile, flamable fluids that can cause intense fires and even explosions...

stcredzero 13y ago
Car explosions have been thoroughly busted by Mythbusters. They are as busted as "Enhance!" Car fires are very real and nasty, though.
sliverstorm 13y ago
High voltage? Do you mean the 12V battery that can't shock you, or the spark ignition that won't do much more than startle you? I've had numerous sparks jump from distributors and plug wires through my hand. They just make your hand numb/tingly. If the jump went in your left hand and out your right, there might be some cardiovascular risks, but that's nothing compared to the risks of 400V @ god knows how many amps.