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White City Streets

04/15/2018 11:10 PM

The city of Los Angeles has come up with a plan to paint all city streets white. A water based coating is to and is being used. The cost is currently $20,000 per mile. The life expectancy is rated at 7 years. It is claimed to reduce heat island temperatures 10*. This effort is being done to reduce global warming.

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#1

Re: White City Streets

04/15/2018 11:28 PM

Los Angeles is painting some of its streets white and the reasons why ...

And according to the Bureau of Street Services, the L.A. streets that have been rendered lighter in color with CoolSeal are 10 to 15 degrees cooler on average than the L.A. streets that have not. That, in turn, keeps the neighborhood from heating up quite as much. Buildings in the area don't need to use quite as much air conditioning, which can curb costs, benefiting residents' wallets and the environment. The innovative sealcoat is admittedly very pricey, with L.A. reportedly footing a $40,000 bill for every mile it "paints." But advocates say its benefits may just be priceless.

I suppose that If I lived there, instead of in the middle of the desert, I might think it was worthwhile.

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#91
In reply to #1

Re: White City Streets

04/19/2018 6:43 PM

The most important thing is that it will give ''Sacrademento'' another reason to raise taxes even higher in ''Taxifornia''...

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#2

Re: White City Streets

04/16/2018 1:21 AM

Chemical Name Amount CAS Number

Asphalt 10-25% 8052-42-4

Water 25-45% 7732-18-5

Aggregate Blend 4-10%

Mixture Polyglass Polymer Liquid 4-10% 107-83-5

Titanium Dioxide 30-45% 13463-67-17

I like the appearance, looks cleaner, and will improve nighttime visibility....I think sealed pavement lasts longer as well....

..at least until it gets messed up with tire tracks and graffiti 'artists' and all the other not white materials that coat the streets....

http://guardtop.com/wp-content/uploads/2016/06/SDS-CoolSeal-By-GuardTop.pdf

http://guardtop.com/wp-content/uploads/2017/10/CoolSeal_trifold.pdf

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#4
In reply to #2

Re: White City Streets

04/16/2018 1:41 AM

When you see roads with reflective white markings in areas with high incoming solar radiation you will notice that the asphalt cracks around the markings first.

There is huge thermal stress on the different surfaces with the white reflecting a lot of radiation and the black absorbing it.

Now I think about some tyre markings on that white coating or dirt and how this changes the thermal stress on the surface and if the expectation of 7 years life time is warranted.

I guess this will be an interesting field test to see the impact and benefits from this.

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#6
In reply to #2

Re: White City Streets

04/16/2018 7:43 AM

Have to keep the Vintage 70's era Harley Davidsons off it... the oil puddles will really show up.

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#31
In reply to #6

Re: White City Streets

04/17/2018 8:50 AM

Also trucks with Detroit Diesel engines; they have a reputation of being leakers. I have heard them described as "continuous oil change."

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#12
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Re: White City Streets

04/16/2018 12:52 PM

My first job at the City of Burbank was applying the hot tar crack seal to asphalt roads. I walked about 15 miles a day spreading that stuff in the street. I do see the benefits of a cooler street as the last time I measured the asphalt in front of my house with a laser thermometer, it read 157 Deg. F at approx. 1 pm on a hot Las Vegas afternoon. Though I do see some drawbacks to the color of white. Tires are black and soon the coating will be a muddy gray color and then the persistent line locator marks. They will need a new "Proposed dig area" color which is WHITE. also, taggers will switch from walls to pristine white streets to display their "artwork". What about lane division? Will that change to black or will they stick with the reflective yellow or some combination of colors? I think they should at least start a study here in Nevada but sadly it seems that Nevada is about a decade behind the "new (anything) tech curve" except in how to fleece the tourists at the casinos, they're REALLY good at that!

And YES, the roads actually looked this bad even after a few years. Most people think that traffic is the major cause of road cracks. Traffic and time is probably the second cause while water intrusion into the compacted underlayment is the first. There is always the contractor cutouts that were improperly compacted and patched that fail early too.

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#18
In reply to #12

Re: White City Streets

04/16/2018 7:04 PM

And if you are a motorcyclist, big fat 'tar snakes' in the road are slippery in high heat. Watch out for them if you are out there scraping your footpegs.

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#3

Re: White City Streets

04/16/2018 1:35 AM

It suggests that global warming is actually a heat island effect!

But it might just be me in a confirmation bias pattern. Who knows!

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#30
In reply to #3

Re: White City Streets

04/17/2018 8:47 AM

"Heat Island" effect fits. As I drive from the small city of Canton, OH, out to home in the country, the temperature drops a couple of degrees. I imagine the difference is larger from a large city.

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#53
In reply to #30

Re: White City Streets

04/17/2018 11:39 AM

The temperature is not warmer in the city than in the surrounding agricultural areas and forests because the city makes more heat. The sunlight is falling pretty much evenly, everywhere. The ag and forest areas are cooler because the plants and trees are storing energy from sunlight in chemical bonds. Much of this, we eat or wear, one way or another.

In so Cal, the cities are actually cooler than the surrounding areas that are still in their natural state, which is desert. There is far more plant life in the cities than in the surrounding arid countrysides.

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#54
In reply to #53

Re: White City Streets

04/17/2018 11:43 AM

Stop confusing people with facts. Preconceived notions cannot be altered by facts when the preconceived notions lead to preferred conclusions.

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#56
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Re: White City Streets

04/17/2018 11:48 AM

Hey, I clearly understand the difference people and facts!

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#58
In reply to #54

Re: White City Streets

04/17/2018 12:15 PM

Faith is the belief in things unproved. Don't want to get in trouble with the theology of science, seeing as how we are in the middle of an inquisition to separate the believers from the heretics.

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#73
In reply to #53

Re: White City Streets

04/17/2018 4:28 PM

cement is a great medium for storing heat. Cities are full of it. homes and businesses give off heat in most places. heat islands are a real thing.

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#5

Re: White City Streets

04/16/2018 5:57 AM

That's a governmental admission that <...global warming...> is not a myth...

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#29
In reply to #5

Re: White City Streets

04/17/2018 8:32 AM

That's a governmental admission that <...global warming...> is not a myth...

It might be considered that, if it wasn't for the fact that we're talking about California here.

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#39
In reply to #5

Re: White City Streets

04/17/2018 10:40 AM

One of the issues with historic temperature measurement is that former measuring stations were located out of the heat island. As municipalities have grown, measuring stations that used to be in grassy areas are now surrounded by pavement and read higher now than in the past.

The result is readings that show climate warming not due to global process, but instead due to local microclimate change. Coupled with arbitrary adjustment to lower previous temperature histories, it's a basis to massage the numbers further to falsely inflate the reported rate of warming.

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#61
In reply to #39

Re: White City Streets

04/17/2018 1:05 PM

Sir,

I thought that some studies have been done using readings from stations that have not had any significant land use changes nearby, with these studies showing small but consistent temperature increases. Also, that the data from stations with significant nearby land use changes has been appropriately treated or adjusted. I suspect you would agree that the topic of climate change and global warming is filled with the difficulty of seeing long-term trends and analyzing their causes, when human interaction with the globe is so short-term.

I suspect strongly the the city of LA has already done some studies of micro climates in the areas where the TiO2 containing seal coat has reduced temperatures and reduced nearby utility usage, to justify its being continued.

I believe humans have caused significant and measurable changes to the world's climate, and that these changes are reversible at this time (but may be much harder to reverse in the near future). I believe that in time, the well-conducted research will yield data to quantify and even confirm this, even though some will continue to hold contrary views (and pronounce them vigorously).

--JMM

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#7

Re: White City Streets

04/16/2018 9:20 AM

I never thought about the thermal stress of markings on pavement. Will be very interested to see how this expensive treatment holds up. I would think the residents are delighted to reduce 'heat island' effects even by a small amount.

Around here all the lines, turning lanes, arrows etc have to be repainted yearly. I guess our solar input is not enough for any color vs solar absorption to make a difference, or we would notice it since there is a yearly crop of major potholes as well from freeze and thaw cycles. Pavement is really perishable.

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#8

Re: White City Streets

04/16/2018 11:54 AM

I seriously doubt it will last seven years. Maybe if you didn't drive on it. And when it gets dirty? After all, we all know it never rains in Southern California.

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#9
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Re: White City Streets

04/16/2018 11:59 AM

its interesting,... but imo, there is a reason why I would never buy white carpeting...

the same could be said for the roads.... just have to wait and see.

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#10
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Re: White City Streets

04/16/2018 12:18 PM

Many of the highways in Southern California are concrete anyways. Seems like that would be a better long-term solution than sealcoating bitumen paved streets.

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#13
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Re: White City Streets

04/16/2018 1:08 PM

Sir Robin,

I do agree on your assessment of a 7 year life cycle. In Burbank we had a 4 year rotation of every city street and the streets that needed "crack seal" even though the street was previously "sealed" and yes, we did take pride in doing a 99% repair because some of the hairline cracks would not hold the sealant. On the return visit there would ALWAYS be a section of what is called "alligatoring" that was too damaged to seal and needed replacement. We used to do the full replacement but now it is subbed out to a contractor.

The picture below is the danger we had to endure when fixing or assessing alligatoring!!! Dang Cracks, or is that Crocks!?!?!?

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#14
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Re: White City Streets

04/16/2018 1:29 PM

What are you crying about. That would be considered a well paved road in Long Island. Your dried dirt hole is less than a half inch deep. My commute includes axle braking craters.

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#25
In reply to #13

Re: White City Streets

04/17/2018 6:17 AM

In the UK the impression is that the potholes get repaired once every century, but there are trials of a self-healing asphalt, the secret ingredient being sunflower oil

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#21
In reply to #8

Re: White City Streets

04/16/2018 10:36 PM

I'm with you - slick white coating in a hilly terrain - recipe for disaster on a bike and probably not a lot better for a car - especially when wet!

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#11

Re: White City Streets

04/16/2018 12:33 PM

Interesting idea but water based? I don't see at all how a water based coating will withstand the mudslide inducing rains.

A legal question also comes to my warped mind. How does a municipality now make lane markings? White paint on white roads will not have a very high contrast.

Also why not use light colored concrete instead of black asphalt?

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#15
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Re: White City Streets

04/16/2018 1:38 PM

Back when I worked with a municipal transportation department, they used the Manual on Uniform Traffic Control Devices as their controlling document for all striping done within the city.

Yellow lines are used to separate traffic moving in opposite directions, and white lines are used to separate traffic moving in the same direction, and on the shoulders of paved roads. On one-directional roads, a yellow line appears on the left shoulder, and a white line on the right shoulder. Passing rules are denoted by dashed lines as in the United States. Orange painted lines are sometimes used when the direction of the road is altered temporarily for construction projects.

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#16
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Re: White City Streets

04/16/2018 3:06 PM

Exactly my point. Those striping colors have a meaning. So a road surface color that obscures the placement of standard color line stripes may not be a safe idea.

I also wonder if the traction will be reduced with a smooth painted road surface.

If any Los Angeles highway department administrators read this, please don't get me wrong I'm trying to bring up things I feel should be examined before implementation. If my topics can be addressed then reducing the solar heat load in a hot city, like Los Angeles, sounds like a great idea.

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#17
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Re: White City Streets

04/16/2018 3:20 PM

what will probably happen is bordering the white lines with a block border...

or have dual lines both white and black....

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#19
In reply to #16

Re: White City Streets

04/16/2018 7:11 PM

It will absolutely be reduced.

Even if they add a traction enhancement (sand) because it will just wear away.

When I am riding my motorcycle in the rain, any painted line is to be avoided if possible because they are slick when wet. Even more so, when they embed the glass beads in the paint for reflective purposes.

Same goes for maintenance personnel access covers, metal plates in construction zones, railroad tracks, expansion joints in bridges, metal grating on lift bridges, etc.

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#47
In reply to #19

Re: White City Streets

04/17/2018 11:20 AM

Then it's time for some enterprising chemist to develop white asphalt.

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#92
In reply to #47

Re: White City Streets

04/19/2018 7:18 PM

Assuming you could find an appropriate white rock, you would still have to ''bind'' it with some kind of white-colored petrochemical (because adhesives, like Elmer's (white) Glue, etc., would break-up far too quickly under the first vehicle to pass over it...)

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#33
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Re: White City Streets

04/17/2018 9:03 AM

I also wondered about traction. Around here a lot of the roads are brick under the asphalt. Some still have the top surface as brick--it's amazing how 100+ year-old brick has stood up; except where it has been dug up for repairs, it is fairly decent. Asphalt lasts only a few years. But I'm off my topic! A brick surface is known to be slippery, especially after a light rain following a long dry spell.

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#20
In reply to #11

Re: White City Streets

04/16/2018 8:00 PM

A legal question also comes to my warped mind. How does a municipality now make lane markings? White paint on white roads will not have a very high contrast.

Hey, good point. How are the "autonomous cars" going to figure out where the edges and center of the road are?

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#42
In reply to #11

Re: White City Streets

04/17/2018 10:58 AM

If it is water based and has asphalt in it, it is an emulsion. Water evaporates after application and the asphalt micro-droplets spread out and fuse together. That's why you can see a bit of steam coming off it when they're out there sealing cracks with the black stuff. Still oil based, one way or another. That's just how they get the environmentalists to sign on.

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#22

Re: White City Streets

04/16/2018 10:38 PM

Oh, this is hilarious! The people in California really ARE crazy, aren't they?

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#43
In reply to #22

Re: White City Streets

04/17/2018 11:01 AM

I was wondering if anyone would catch this: Where does the reflected heat go?

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#50
In reply to #43

Re: White City Streets

04/17/2018 11:24 AM

Someone else's back yard.

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#65
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Re: White City Streets

04/17/2018 1:42 PM

To get your own invisible lock box, just send $99.99 to:

Invisible Locked Box with Key

C/O Al Gore

Montecito, California

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#66
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Re: White City Streets

04/17/2018 2:02 PM

To get your own invisible lock box, just send $99.99 to:

I ordered one but it arrived scratched!

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#67
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Re: White City Streets

04/17/2018 2:09 PM

Not a problem, its under warranty.

Here in my hand is the invisible repair kit, and all you have to pay is the shipping and handling which is $9.99.

btw, as you can see, our warehouse is overfull and passed capacity

so we are running a special,... buy your second Invisible Locked Box with Key, and we'll included the Invisible Repair Kit FREE!

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#69
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Re: White City Streets

04/17/2018 3:13 PM

Here in my hand is the invisible repair kit,

But are the instructions clear enough?

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#70
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Re: White City Streets

04/17/2018 3:17 PM

I think I'm beginning to see right through it, clear as day.

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#71
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Re: White City Streets

04/17/2018 3:17 PM

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#76
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Re: White City Streets

04/18/2018 3:00 AM

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#51
In reply to #43

Re: White City Streets

04/17/2018 11:34 AM

it was in post #27

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#72
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Re: White City Streets

04/17/2018 4:17 PM

It actually reflects light instead of the light being absorbed and converted into heat. A white surface will reflect more light back into space.

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#48
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Re: White City Streets

04/17/2018 11:24 AM

If you lived there, you wouldn't notice as everyone is that way, though I live in the Portland area and I still notice the craziness every day.

I realize this is a gross simplification as it applies primarily to the southern and western state of California. After November that may change if the move to split California into three states passes on the ballot.

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#23

Re: White City Streets

04/16/2018 11:33 PM

How painting the roads would reduce global warming, is doubtful. Prima facie, the sun gives energy relentlessly. Whether black or white surface receives thermal energy, or not, it has no bearing on global warming, since by having a white surface, I am sure the heat is not reflected into space. The reflected space first heats the atmospheric air, and what little heat that gets out from the rarefied air near the stratosphere only would get out.

Perhaps the better idea would be create artificial clouds over a city or town, to act as an umbrella, which, if it is sufficiently above the earth surface, might reflect the sun's thermal radiation into space.

We in India, do this white painting on the top of the roof, to keep the houses cooler by about 3 to 5 degrees, but the negative point is, that it makes cracks in the roof concrete.

Nothing is truly black or white in the world !

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#26
In reply to #23

Re: White City Streets

04/17/2018 7:14 AM

As I understand it if you ask a glider pilot where he gets the most thermal lift,... over rough terrain or over a city parking lots... it would be over black top.

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#49
In reply to #26

Re: White City Streets

04/17/2018 11:24 AM

They fly around here all the time and it is typically above the windward slopes. They get their lift from wind rushing up the slope. You never see them over city parking lots, mostly because it's illegal. However, if you think about a gentle warm updraft and compare that to a 20 mph or greater wind rushing up the face of a hill or mountain, well, I think you get the idea.

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#96
In reply to #49

Re: White City Streets

04/28/2018 12:40 AM

Glider pilot here. It's certainly not illegal to fly above a parking lot, as long as the legal obstacle clearance is maintained.

Yes, gliders circle above hot surfaces because they heat the air above, which rises.

A light colored surface reflects infrared radiation (heat). This does not generate lift for a glider. A dark colored surface absorbs the infrared radiation and gets warm. This warmth is transmitted to the air above via convection, which causes the air to rise, which in turn causes the glider to rise.

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#97
In reply to #96

Re: White City Streets

04/28/2018 3:40 AM

As I understood it, gliders use to use the planted farm fields to generate the lift from the heat... but the black asphalt was better.

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#28
In reply to #23

Re: White City Streets

04/17/2018 7:19 AM

If painting the roof keeps the house cooler, why do you doubt that painting the road keeps the earth beneath cooler?

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#37
In reply to #28

Re: White City Streets

04/17/2018 10:08 AM

Because nobody lives below the roads painted, obviously,

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#24

Re: White City Streets

04/17/2018 2:39 AM

So is this an eggshell white or a semi-gloss?

But seriously, people posting here are right. The white will reflect the light adding more distraction to drivers. I typically always wear sunglasses in the winter here in MI because of the light reflecting off the snow whether it's sunny or cloudy. I cant imagine my eyes having to constantly adjust every time that I look at the road and then again at obstacles in front of me.

I just see the number of accidents going up because of this. But then again... I don't pay taxes in CA so my opinion doesn't matter.

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#27

Re: White City Streets

04/17/2018 7:17 AM

A few things that may be an issue here is,... coming from Wisconsin winters, driving in the white snow cover, the suns reflection off the snow can be brutally intense.

I wonder how this will effect driver comfort. Because without some type of eye protection, it can get pretty grueling and tiresome.

The other issue I have is this;

This effort is being done to reduce global warming.

Since the heat is in the atmosphere, its already in the greenhouse. All what they are doing is reflecting the heat somewhere else in the green house.

I have to ponder this for a bit with what the ice caps reflect heat.

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#32
In reply to #27

Re: White City Streets

04/17/2018 9:01 AM

What you say is true, but I think the point here is less AC being used to cool the buildings in the area. Less electrical use means less nasty gases going into the air. It's a chain reaction thing. Maybe even other benefits that I'm missing.

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#34
In reply to #32

Re: White City Streets

04/17/2018 9:15 AM

I thought as much. Almost like higher smokestacks does nothing for the environment; it just puts the particulates higher for the wind to disperse and move them out of the area.

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#35

Re: White City Streets

04/17/2018 9:59 AM

At least they haven't gone straight to a mirrored surface! It is "Tinseltown" by the way.

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#40
In reply to #35

Re: White City Streets

04/17/2018 10:41 AM

They might stare into the road far too often if it was a mirror. Some of the perverts might like it.

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#44
In reply to #35

Re: White City Streets

04/17/2018 11:15 AM

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#94
In reply to #35

Re: White City Streets

04/22/2018 10:06 PM

Don't give them ideas!!!

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#36

Re: White City Streets

04/17/2018 10:05 AM

Will it reduce global warming to any degree? Bad pun, but seriously...also - nod to phoenix911 on post #27.

Seems to me that there are no studies explaining how the green-house gas global warming "thermal blanket" or the increased green-house gas layers are going to allow much of the reflected solar radiation off the planet. Won't warmer upper atmosphere balance out slightly cooler streets?

Aren't you just reflecting SOME of the solar heat gain out to the reflective green-house gas layer where it continues to raise the ambient temperature, while the rest still warms the whiter pavement? Okay, so lower energy consumption for AC during the day, other smaller savings in the cityscape - will it be worth it? Don't get me wrong, I am for reducing global warming...

I may be thinking simplistically - I'm just a physician, not an engineer - but I've seen things that bother me in medicine. An example - let me give you something for your bone density, oh, let me give you something for your indigestion, oh, lets follow up on your bone density with another scan, oh, you aren't absorbing enough calcium (hmmm, did we put you on something for indigestion that reduced your "bone salt" absorption?), I guess you are just getting older and these things happen! I never practiced that way and thought it was a stupid way to "help" people. Better to eat healthily every day even if fast food and comfort food are easier and available nearly everywhere.

So - we reflect the sun more but still have the "green-house gas" situation going on - will California be throwing money away for negligible effect? Are we discussing a project that should - in theory - reduce surface temperatures and have no other side effects that change other impactful natural climate fluctuations? What does a warmer upper atmosphere do to rainfall? I'm out of my league pondering the actual repercussions, but I'm just playing devil's advocate - will the painting of asphalt be worth the financial and consequential costs? After all, are concrete roadbeds that much cooler? Down south (Louisiana) they seem pretty damn hot in the summer (again - anecdotal, not evidence based on my part, could just be my perception)!

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#45
In reply to #36

Re: White City Streets

04/17/2018 11:16 AM

The parameter used to describe what happens with reflective surfaces is called albedo. It's a measure of how reflective a surface is and how bright it appears as reflected light when viewing from a distance

The effect on transmission of radiation through greenhouse gasses is a low percentage of the radiation passing through it.

For the painting to have zero effect on climate temperature, the earth would need to appear totally black in the infrared and optical radiation frequencies.

Global temperature is a huge balance equation with heat sources from incoming solar radiation, addition of solar wind particles and radioactive decay in the mass of the earth. Heat outflows are primarily radiation in the electromagnetic spectrum and some loss due to atmosphere being lost to surrounding space.

I've always thought that if everyone would put a large mirror on their roof and dump a large fraction of the incoming radiation directly back into space, we would probably have a much greater effect on heat balance. The nice feature is that it would be a totally passive heat rejection process.

But then I also liked the prospect of dumping a freighter load of ferric chloride into equatorial waters to trigger an algae and plankton bloom to generate an upcoming ice age by sucking all the CO2 out of the air. (Super villain laugh: Bwa-ha-ha)

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#52
In reply to #45

Re: White City Streets

04/17/2018 11:35 AM

Oh if only there was some scientific way to measure the spectrum of a light source and see how much gets absorbed and how much gets transmitted through a gas.

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#57
In reply to #52

Re: White City Streets

04/17/2018 12:10 PM

Hark, I hear your cry. This wondrous device is named a "gas absorption spectrometer" and it measures the amount and frequency of radiation transmitted through a gas sample and the amount and frequency or radiation absorbed by that same sample. 'Tis truly wondrous and has only been in use for the last century or so.

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#62
In reply to #57

Re: White City Streets

04/17/2018 1:07 PM

If such a wondrous device actually existed then one might also be able to compare the emission spectrum and intensity of a light source through space, a gas and then the difference in that light after that light reflects on a painted or unpainted surface be it egg shell or flat texture. The usefulness of such a device would make this debate moot.

Nay, I say. Such a device cannot exist for it would surely stifle all but those belligerent knaves who only bellow to hear their own exhortations.

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#63
In reply to #62

Re: White City Streets

04/17/2018 1:24 PM

Hark, fellows bellows. 'Tis the nature of the knavish brutes. The wondrous device DOES exist, tho ofttimes the reading therefrom are coloured by the predisposed shadings of the spectacles of the predisposed readers, hence leading to THE PREDICTIONS OF CALUMNY AND DOOM.

Blame not the messenger.

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#68
In reply to #63

Re: White City Streets

04/17/2018 2:14 PM

Might this be why rose colored welding goggles are made?

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#80
In reply to #52

Re: White City Streets

04/19/2018 1:55 AM

The closest thing I can see that would do something of that is the experiment physicist John Tyndal did in the 1800’s which actually discovered the effects of radiant heat absorption of gases.

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#81
In reply to #80

Re: White City Streets

04/19/2018 7:30 AM

I'm not surprised the only experimenter studying light on gasses you know of is one physicist and that one died one hundred and twenty five years ago.

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#82
In reply to #81

Re: White City Streets

04/19/2018 8:40 AM

On your train of thought, since Einstein has been dead for 60 years, would that make his contributions to physics questionable also?

yes, John Tyndal, was a physicist and even though he died over 125 years ago, he's basically the father of the understanding of the effects of greenhouse gases.

So I don't understand the point your trying to make with your post in response to mine. I listed a scientific experiment that would closely compare to the your post of;

"Oh if only there was some scientific way to measure the spectrum of a light source and see how much gets absorbed and how much gets transmitted through a gas."

Which answered your question and instead you come back with a "at this point, what difference does that make attitude?"

Physics does not have a shelf life, and I'm surprised of your response.

So, I'll ask this, Is CR4 for discussion where solutions or understanding can be presented or does your discussions only consist of discussion that are only one-sided and beat-down the ones you disagree with as you have shown.

Maybe you should reflect on you own thoughts (last paragraph)

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#83
In reply to #82

Re: White City Streets

04/19/2018 9:05 AM

Maybe you should reflect on the meaning of the word "stifle" and ask yourself why you continue to protest.

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#84
In reply to #83

Re: White City Streets

04/19/2018 9:11 AM

I understand, your response disappoints me, but is another example from yourself when your talking points become indefensible... Let the beat down begin.

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#89
In reply to #84

Re: White City Streets

04/19/2018 2:19 PM

I clearly see that you do not understand. You do not understand despite my use of verbose, yet simple logic statements. I even attempted to clarify your clouded thoughts by providing a definition link to a word that might not be in your common vernacular. You also seem to be incapable of tying my comments on this branch to my GA comment or the statement Phys made that I was commenting about.

Ironically, you yourself identified the scientist often considered the founder of gas absorption and reflection spectrometry and still you choose to refuse to recognize or understand these results. To add to this irony you highlight my ending paragraph where I identify only a belligerent knave would continue to argue when testing would not only be possible but repeatedly performed after more than a century of testing being possible.

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#90
In reply to #89

Re: White City Streets

04/19/2018 2:39 PM

I really don't care of the exchange you had with phys, while valued, I'm talking about your sarcastically question of;

Oh if only there was some scientific way to measure the spectrum of a light source and see how much gets absorbed and how much gets transmitted through a gas.

I answered it and anything else no matter how eloquently and derogatorily stated of which you responses demonstrated, as nothing more then a defense mechanism, and is a diversion from the point you can't defend.

But you seem to enjoy a little sidebar that amounts to nothing more than patting yourself on the back on how much more superior you are to others.

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#38

Re: White City Streets

04/17/2018 10:18 AM

I wonder about the consequences (and lawsuits) when the Titanium Dioxide* wears off and is washed into the storm drains and the "spotted belly whatzawhozit" gets cancer (even if it is at 10% of the previous rate, environmental lawyers and California courts don't care). Or if detergents have to be used to clean the streets and their effects?

*Titanium Dioxide seems to be fairly inert, but if it is crushed by traffic into nanoparticles then there can be ill effects to those breathing/ingesting them.

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#46
In reply to #38

Re: White City Streets

04/17/2018 11:19 AM

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#60
In reply to #38

Re: White City Streets

04/17/2018 12:55 PM

Titanium Dioxide vs Retro Reflectors

Our brilliant marketing gurus use titanium dioxide in some of our toothpastes, apparently since whiter paste means whiter teeth[sic] to their idiot consumers. Use sodium bicarbonate(USP) dampened with hydrogen peroxide(3%) instead for a far superior toothpaste. DIY toothpaste's biggest downside is that it does not generate cash flow for large corporations who train everyone to believe that the taste is intolerable and that the seconds it takes to prepare is unacceptable.

Regarding titanium dioxide road use, the cost is too high and, as others have observed, the coating will quickly wear. The supply is not infinite and with massive use the costs will rapidly escalate. Many white paints already use alternatives which are not white in the infrared and many people have discovered that painting the west side of their house white does very little unless the titanium additive is a substantial proportion of the paint recipe. Roof surfacing is a smarter use and foamed concrete roof tiles with the upper surface liberally dosed with titanium dioxide makes a lot of sense in sunlight rich locations. Neighbors sometimes suffer when their windows face a titanium dioxide reflective roof.

Another characteristic of titanium dioxide is that it reflects light in a more diffused way than a mirror so heat gain through a white-surface-facing window has a very long duty cycle. A superior way to reflect solar radiation back into space would be retro reflectors such as the glass beads on traffic signs. These send light back toward the original source(back into space in this case where the sun is) rather than through your neighbor's window. Unfortunately, glass beads retro reflect visible light only(just small amounts of infrared and ultraviolet get retro reflected) so the total energy sent back into space is a small fraction of the total radiant energy arriving from the sun. Nonetheless, any radiant energy from the sun sent directly back into space would have a long term lowering impact on earth's average temperature. Deployment of visible light retro reflective roofing might (at least initially) be a problem for airplane landings at night.

There are other ways to create retro reflectors which do broader spectrum work. These should be investigated for optimum roof operation.

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#41

Re: White City Streets

04/17/2018 10:46 AM

Finally - I've wondered for years why they didn't do this in geographical locations with an average high temperature . We definitely don't want that up here in 80" average snow fall country. Mid March we pass into that time of the year where road crews seldom dump salt as the solar radiation on the black asphalt deems that unnecessary. But, in California, Arizona, Texas and so on, with little snowfall to deal with, this seems a perfect solution for summer heat.

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#55
In reply to #41

Re: White City Streets

04/17/2018 11:46 AM

The white roads simply reflect the heat back into the atmosphere. The best way to "get rid of it," is to plant more plants and trees. They store sunlight energy in chemical bonds via photosynthesis. This can then be composted and used for fertilizer for agricultural crops or eaten directly. Even if it's buried in landfills, it's pretty much taken out of the environment for an indefinite amount of time.

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#59
In reply to #55

Re: White City Streets

04/17/2018 12:30 PM

I'm amazed. You got that one pretty nearly entirely backwards.

Light reflected from earths surface passes through the atmosphere and only a fraction is absorbed by the atmosphere. The balance is radiated into space and it's gone. That which is captured by the atmosphere continues to radiate a lower light frequencies until it finally also radiates into space and is gone.

Light absorbed by plants and converted to chemical energy is retained in the environment and subsequent transfers of that energy from plant to creature to soil or to geologic formation all add heat back to the environment through entropy. The only final way to get rid of the energy is to radiate it back into space.

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#74
In reply to #59

Re: White City Streets

04/17/2018 5:52 PM

I'm glad you noticed! The whole concept of carbon based global warming is based on how much heat the 0.04% of air that is CO2 prevents from leaving the atmosphere. There are also other mechanisms that capture small amounts of heat that would otherwise be lost to space. So, by presenting the concept that reflecting heat does not get rid of it, we make those who call us deniers think about the physics.

Heat stored in chemical bonds by biological activity greatly reduces the actual amount of heat energy in the environment, to the point that it can be completely out of the picture for hundreds of millions of years, until something unearths it and breaks those bonds. Yes, it's all entropy, but not all at the same time! That's why plants and animals that lived over 60 million years ago are once again releasing solar energy back into the environment.

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#87
In reply to #74

Re: White City Streets

04/19/2018 11:03 AM

Photosynthesis Action Spectrum

David,

Photosynthesis does not directly store heat. The photosynthesis action spectrum(where it works) is blue and red light. It is true that if that red and blue light is absorbed by some surface not performing photosynthesis that the energy contained will be re-radiated as heat. Storing energy on the earth opens the door to many processes which can later release that energy as heat. Photosynthesis does not annihilate energy, it stores it. Natural or human caused processes will most likely in the long term release that energy as heat. Reflecting light or heat back into space gets rid of that energy now. Reflecting red or blue light directly back into space from some fraction of the earth's surface can easily be greater than fifty percent efficient unlike the photosynthesis process which is generally considered less than ten percent efficient. It is true that photosynthesis can, with very large scale efforts, lower atmospheric carbon dioxide but it will take a staggering increase in green stuff today to significantly offset the fossil fuel releases since fossil fuels have been accumulating and concentrating carbon for geologic scale time.

The photosynthesis action spectrum is a fraction of the visible(or nearly visible) spectrum and the visible spectrum is a small fraction of the solar radiant energy spectrum. It is true that plants grow on their own but they are already doing that. Also, humans will search for any large deposits of energy stored by photosynthesis to get some of that energy back. These energy recovery processes generate far more heat than light and the heat they generate has a much harder time running the atmospheric absorption gauntlet than red or blue light does. Also, natural processes may well re-oxidize the stored carbon releasing heat into the atmosphere. The take-away thought is that we would have to change our behavior significantly to get on the right side of the carbon/carbonDioxide budget before we could perceive lowering of average global temperatures. The oceans buffer terrestrial carbon dioxide levels and this will delay any intentional results involving the carbon budget. I am not saying that raising the living photosynthetic ratio will be absolutely ineffective just that the effect will be difficult to measure and perceive.

Humans already know that trees can reduce urban heat island effects locally and are currently participating in efforts along those lines such as some small efforts here in Austin, TX where I am now. To expect measurable global effects one would have to entertain much larger scale efforts such as the ocean iron enrichment someone else mentioned. These can easily cause large scale unintended consequences and should therefore be studied until we have great confidence that we understand them thoroughly before we consider even experimental major deployment.

Retro reflectors have both local practical impact(a cooler house under an rr roof) and a more easily measurable large scale impact(use remote sensing satellites). There is reasonable confidence that rapid reversibility is accessible(paint over that rr roof), tunable(paint half of them), and well understood(the homeowner can understand it and do it.) Short of overheating the sun or alerting hostile ET's, unintended consequences are arguably unlikely.

My political mindset follows. Humans are conceited. They make incorrect choices based on "science" which is their euphemism for their favorite guess on what actions mankind should be forced to take to insure or improve his future. These guesses are often the cause of catastrophic collapse of otherwise stable natural phenomena. Therefore, I intend to discourage any large scale(lets convert all of our roads to titanium oxide coatings) the instant it fails my sustainability or limit tests. Q: Do we have enough titanium ? A: No. C(onclusion): Do not do that.

I do not even have to ask questions about effectiveness. However, I casually can determine that since vehicles are not typically running over our roof surfaces, that roof surfaces are a better place to deploy expensive titanium than roads, therefore do not deploy titanium on roads. And the conclusion is not to deploy titanium on roof surfaces, just do not deploy it on roads. Carefully consider your roof surface strategy without leaping to the conclusion that titanium is the best strategy there simply because titanium will do better there than it does on roads.

QEDERI(quite easily proved[QED] an economically ridiculous idea)

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#64
In reply to #55

Re: White City Streets

04/17/2018 1:35 PM

So you are suggesting we drive on grass covered roads in the city? Planting trees is a wonderful idea, until someone hits one beside the road.(street) We had trees on every street in the town I grew up in until lawyers and lawsuits became fashionable. Hit a tree and sue the municipal authority for leaving it there beside the roadway. Slip on the leaves in fall and sue the sidewalk owner for physical pain. Don't think anyone will be suing for white road covering, and it reflects the solar radiation back to the atmosphere, not the heat. No heat until that radiation is absorbed by something.

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#75
In reply to #64

Re: White City Streets

04/17/2018 9:14 PM

The point is, black absorbs heat and white reflects it. OK. Black roads absorb heat. But there is a limit, after that the excess heat, just goes to heat the atmosphere around it by slow emission. Only factor is, the absorbed heat is given out by the black surface, long after the source of heat is removed.

The reflected heat, of a white surface, goes to heat the surroundings, depending upon the angle of incidence, and the buildings beside the white painted road, are bound to be hotter, at least on the side adjacent.

It is like throwing our garbage into the neighbour's yard, rather than making any dent on global warming.

The only positive possibility is, if a white painted road surface lasts longer than a regular black one, some economy is achieved.

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#77
In reply to #75

Re: White City Streets

04/18/2018 8:27 AM

You are making the same minor error others have - the white surface is not reflecting heat - it is reflecting solar radiation. Again - no heat until the radiation is absorbed. Minor point in use of terminology as the end results are still the same.

The reflected radiation will be absorbed by the surrounding buildings, I agree, but most of them are not black, so they absorb a bit less, and many have mirrored glass. Much less radiation will be absorbed and a cooler city will be the end result. How much less remains to be proven.

Who brought up global warming? This is an attempt to make city life more tolerable in warmer seasons with little cloud cover. You can feel a distinct difference driving from a city to the country on sunny summer days, and even more so at night. They are trying to reduce this difference a bit - that's all.

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#78
In reply to #77

Re: White City Streets

04/18/2018 9:00 AM

Stop confusing people with facts they don't want to know.

Whenever anybody even mentions the idea of air temperature or weather and California in the same thread on CR4, somebody will mention "global warming" and we are off to the races. Another thread will now be hijacked into an incessant exhortation of bellicose ignorance and political bias. "Global warming" has become CR4's version of Godwin's Law.

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#79
In reply to #78

Re: White City Streets

04/18/2018 9:34 AM

I was thinking the same thing when I responded to that post, but didn't want to go as far as you did with it, to avoid another 100 posts, half of which will involve me. I am a bit busy right now to get into that over discussed topic.

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#85

Re: White City Streets

04/19/2018 9:18 AM

In Chicago we are always "cooler by the lake"

The meteorologist always says so..

Add lakes, love the weather of your climate or move. ?

Let's paint Canada black to make summer warmer..

When does it stop?

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#86
In reply to #85

Re: White City Streets

04/19/2018 9:23 AM

you have the northerly wind coming off the lake with nothing to stop it. And as its coming over the lake its picking up moisture.... and below is a picture of the results this time of year.

it a picture of a Snowstorm.... but you already know that.

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#88

Re: White City Streets

04/19/2018 11:47 AM

...and, are they going to paint the lane lines black?...

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#93

Re: White City Streets

04/21/2018 9:37 PM

Lots of wonderful comments.

I'd like to make one.

If you drive around the Los Angeles basin, you will see a painted message near most storm / gutter / rain culverts etc.

Drains to ocean.

This was started from a program to remind the general public that poluttants can be washed down the gutters into the ocean. I remember seeing people actually pour antifreeze, oils, pesticides even paint into those drains.

I see that Solar Eagle provided a breakdown of the coatings components. My thoughts were along the lines of the materials in the coating and in combination with other compounds found on city streets being washed into the ocean and what possible effects there might be.

I checked Google and I wasn't able to identify an evironmental study done to determine adverse effects.

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#95
In reply to #93

Re: White City Streets

04/22/2018 11:26 PM

tonyhemet,

Most or all of those ingredients are the same ones (perhaps other than the TiO2) used for many years in typical seal/slurry coatings. Perhaps your desired data on the components would be found by looking up the SDS pages on the coating and then on the individual components.

Thanks--JMM

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