sammy

For anybody who lives with winter road conditions...Why do we use sodium chloride on the roads? Is it widely used or is it only in the rust belts that it is found?Is this the same stuff that is applied to gravel roads to keep the dust down?
It came to my mind, as a few classics are squeezing in a last ride and got caught out after a nice fresh batch of sodium chloride had been applied to the highway

1969w3155

Just to **** us off! To melt ice on the roads, where slick conditions might cause braking/sliding/vehicle control problems, aka accidents.

at3reg98

I've been out when this stuff was put down (I actually saw the truck up ahead!)and had to turn around to avoid it. I don't know how much more harmful it is compared to road salt but I can't imagine it's any better to have splashed up underneath the car.

rustyroger

Sodium chloride is common salt aka table salt.

It is used mixed with fine grit in the UK as a means of preventing road surfaces icing.
It is cheap and relatively harmless in small quantities apart from damaging to the metals used in making cars.
Over use has harmful effects on the local environment, but it is the most cost effective way of keeping roads surfaces ice free.
For those of us with cherished cars the best thing to do is not use the car during winter months.

Roger.

MDchanic

I hate road salt.

Except when I'm on my way to work at O-Dark-Thirty, it's been damp, and the Black Ice is waiting.

Then I pray for it.

- Eric

1970cs

Yes, it is the same stuff used on dirt roads for dust control. My dealership lot was at one point in time dirt/sand mix which when dry is very powdery we used it to keep equipment and vehicles dust free for about 3-4 months.

In central Michigan it's mainly a rock or crystal type salt put on our roads. DD usually get an under carriage wash when washing the top side!

Pat

sammy

I have heard that there is some type of bonding agent mixed with the sodium ...that makes it actually adhere to metal making it impossible to rinse off the undercarriage...at least with salt and sand it can be removed.
Just trying to understand it....they apply it when temps will be hovering around that freezing mark to attract any moisture that has the potential to freeze making black ice?I know when I apply it to my yard in the summer to keep the dust down when we are working, the soil becomes darker (moister).......

2blu442

Interesting how things vary around the world.

We don't use salt on the roads in Oregon which is good for our old cars. But the Cascade Mountain Range has lots of cinder cones that are mined for road rock and sanding. The cinder is so abrasive that it takes paint off and even pits the windshield glass.

For dust abatement on gravel roads we usually use Lignin Sulfonate. Its more friendly to the environment. Here's a link taking about it.
http://www.pacificdustcontrol.com/lignin-sulfonate/

aliensatemybuick

Actually it is Calcium chloride or in some cases magnesium chloride that are used to reduce dust on gravel roads

MDchanic

Oh. CaCl and MgCl are entirely different ionic compounds than NaCl.

I was trying to figure out why someone would spray salt on their yard. The Romans used it to prevent anything from growing.

All three of these compounds works by dissolving in water, thus depressing it's freezing point, which has the effect of melting the ice

On your car, all three provide free ions, which facilitate the conduction of micro electric currents, which cause galvanic effects, which cause oxidation (rust).

- Eric

Tony72Cutlass'S'

When i was in seattle they were using some other stuff that doesnt work.

Montreal is supposedly the heaviest salted city in the world. And it's probably a testament to why our roads are so bad.

Koda

Sodium chloride, like others have said, IS salt. There's nothing uber special, bonds to your car, more horrible, about one term or the other. Sand is for traction, and salt moves the phase change down some degrees. You can actually salt your cooler and make it run a bit colder. The idea is that, by the time it gets cold enough that salt won't work, it is usually cold enough to not ice in the first place. This, of course, doesn't consider cold snaps, where the ambient is way below freezing, yet the ground is above.

Edit: salt I don't think hurts roads too much. It's the freezing/thawing cycle and the frost heaves that does it.

auto_editor

Eek. In SE Michigan--or at least around the Belleville/Ann Arbor/Ypsi area--they use a fine mica-like sand that is more about providing traction on the snow than causing the snow to melt.

It is much better for the environment because anything green the salty run off touches will die and for your car because salts facilitate rapid oxidation.

[And as "inhibiting" is the best we can do against rust, I am more than happy that my area has gone salt(s)free.. ]

jaunty75

Here it is, the relevant portion of the NaCl/H2O phase diagram. At any weight percentage up to about 25% NaCl, the freezing temperature of water is lower than pure water. This works to a "maximum" of about -21C or -8F. Colder than that and the salt has no effect.

11971four4two

the last few years they have been adding beet juice and ethanol corn fuel by products to the ice melting salts. nasty stuff


http://articles.chicagotribune.com/2...oad-salt-brine

1969w3155

I have gone to the Detroit auto show (N.A.I.A.S.) before in nasty weather, and everything gets coated in salt, the entire car, windshield, side glass etc. When the forecast is bad, I will take two jugs of windshield washer solvent, because they use so much salt that the washers are on constantly.

Nilsson

You can actually hear the cars rusting during the winter here in Ohio.

BlackGold

My theory is that's exactly why salt hurts the roads. Snow and ice freeze on the road and in its cracks, then salt is applied and melts it. Then more snow and ice freezes, then more salt melts it. Instead of leaving the roads frozen, the city forces daily freeze and thaw cycles.

Several years ago they experimented with some new chemical in my neck of the woods. The stuff was so corrosive that all the license plates corroded within a couple months. Many cars today (including my own) still sport those rusty plates, nearly obscuring the letters and numbers. I'm still waiting to have a cop pull me over and insist I get new plates. He'll get an earfull from me; the government creates a problem then expects me to pay for their mistake.

jag1886

That's the way it was when I lived in Omaha, you had to buy a new car every 7 years because the door skins where flapping. All the cars where white in the winter no matter what color they really where.