Rank: Forum user 
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I had a conversation today on a construction site with a contracts manager,
I advised we order grit for the walkways & scaffolding
He contracts managers responce was - Grit is no good in tempatures under 0-
Can anyone clarify this or is it a money saving scheme
Any help would be gratefull as i believe we should distrabute the grite in any case
JMc
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Rank: Forum user
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I would imagine that it's similar to highways usage - so called 'grit' has a salt content to help melt ice and the larger 'grit' helps provide traction.
Walkways definately should be gritted, if the scaffolds are that covered in snow or ice how safe is it to be working there? I'm not sure of the effects of grit on scaffold boards either so that may also be something you want to check.
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Rank: Forum user
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I'd be tempted to ask him where he got his information from? Then call a supplier and find out from them.
If grit is no use in minus temperatures then why are local authorities falling over themselves to get some to spread on the roads?
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Rank: Super forum user 
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How often does it freeze above freezing?
Common salt (NaCl) chanegs the freezing point of water to somewhere around -5 if I rememebr correctly, other salts may alter it further still. Add in some sand for grip and...
get gritting :)
A horrid side effect is a rusty car :(
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Rank: Super forum user 
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The whole point of grit, or more correctly, rock salt is to reduce the freezing point of water down below 0C. It does this by partially dissolving in the water. This action melts the snow / ice because the freezing point of the resulting solution is lower. I believe that this becomes ineffective around about -6C, which would be the freezing point of the resulting solution, but I am not absolutely certain of that figure.
Your contracts manager has either genuinely misunderstood what he has been told or just doesn't want to grit the site
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Rank: Forum user
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I'd go with the "Doesn't want to grit the site" option.
Thanks for the technical information Peter - makes sense now one comes to think about it.
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Rank: Forum user 
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Some information
Salt will melt snow at temperatures as low as -20° C. However, salt starts to become less effective at minus 5°C and almost ineffective at lower temperatures. As a result, it use becomes practically, economically and environmentally difficult. In extremely low temperatures, or heavy snowfall, a mix of salt and grit may be used to aid traction.
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Rank: Super forum user 
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I can suggest an alternative to salt if you are interested - it doesnt rust, is eco-friendly and is more efficient than salt in terms of coverage and effective at lower temperatures. It is something I used to use a few years ago but found it worked well. I have no connection with the company but PM me if you want the company name for you to follow up.
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Rank: Guest
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It may also be that he is talking about grit sand, as apposed to grit salt.
Grit sand is OK near to freezing, but no good once the Ice and snow sets in.
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Rank: Forum user
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Surely the point Mr H&S needs to make is that the scaffold etc should be treated with something to dissolve the ice / snow to make the workplace safer for his employees?
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Rank: Super forum user
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Your managers is either misinformed or__________ For a detailed answer, refer to:- http://antoine.frostburg...why-salt-melts-ice.shtmlThe lowest temperature possible for water-salt solution is -21.1 C. The depression of the freezing point is also dependent upon the salt solution concentration
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Rank: Forum user
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Hi All
Thank you very much for your reply's
since my post we have closed the site until the thaw starts,
Once the thaw starts we would remove the snow from the walkways inc. the scaffolding walkways & apply grit.
The CM was slightly out as most of you stated not -0 but -6 grit becomes inaffective
this is what I was looking for & although found the info in the net your reply's were appreciated & thats what this forum is for
Thanks again
Keep safe
JMC
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