As somebody pointed out on the widnes messageboard,any plastic material becomes hard and rigid in cold conditions,like a garden hose pipe in winter for example which then becomes soft and flexible in summer.The blades of 'grass' would have been like spikes on Friday at minus 3 degrees.There was another game played on the i pitch on Sunday afternoon when the temperature was around plus 3 degrees,not heard any complaints from players in that game.Perhaps games should be canceled in extreme conditions or if not advise the use of knee and elbow protection.

It was a local chemist. I'm not sure if he was talking about the pellet infill, the grass or both.

Quote
[i"first post as a chemist of 50 years standing .the problem probably is that all plastics as the temperature drops become harder and brittle giving sharper edges.if you want to prove this place any plastic kitchen utensil that is soft and flexible in the freezer and see what happens. the pitch is still better than turf at the same temperature .surely the answer is under these conditions to wear elasticated knee and elbow bandages job sorted"[/i

You're right with this bit.



But you're wrong, here. So long as body heat is being used to provide the latent heat required for evaporation, heat is being transferred from the body to the evaporating liquid - which is the same thing as saying that the body is being cooled. It doesn't really matter whether the liquid is next to the skin, or whether the skin is open to the air. All that matters is being able to transfer heat.

Also, moisture close to the skin will only heat you up (i.e. transfer heat to you) if the moisture is
hotter than you are (second law of thermodynamics). It will just fail to cool you if there is no opportunity to evaporate.

We're ignoring the efficiency and degree of cooling, so far. It can be more efficient to cool the body without having a layer of material in the way: evaporation is 'easier' when the air into which the liquid evaporates is drier/less humid, but a layer of material can trap vapour, saturating the air and making evaporation impossible; you still sweat, but it just hangs around at about the same temperature you are (this is one reason why the same temperature can feel 'hotter' and 'stickier' when the weather is humid). However, modern 'technical' fabrics that wick moisture from the skin use capillary action to get the moisture out to the material surface and away from the skin (reduces chafing, feels nicer and drier, with more efficient cooling than other materials, like cotton). Here, body heat warms the fabric, and the air between the body and the fabric. Excess body heat results in sweat, which is carried away from the body to the fabric surface, where it evaporates, cooling the material, and the body. Heat transfer and cooling may be less efficient than standing naked, but it's not true that wicking fabrics don't work, or that they don't cool you by evaporating sweat.

That said, there's a time and a place for them, and I wouldn't fancy playing RL in full skins in a hot summer, myself. As it happens, I wouldn't expect there to be too much problem with Widnes' pitch by the time it's that warm, either.

If the latent heat can't escape while the body continues to produce heat, wouldn't the temperature gradually increase? But fair point, I should probably have said 'won't cool you down', rather than 'heat you up'. I was picturing wearing an inefficient skin trapping moisture against the skin, also being worn beneath a playing top, with heated air and moisture having little opportunity to escape.

You've explained it pretty much as I understand it, although my understanding is that the actual sensation of evaporative cooling against the skin also helps make the skin feel cooler? Either way, I seriously doubt the effectiveness (or wisdom) of wearing such skins in peak summer temperatures when the natural cooling process is more efficient.

Yes, except that technically heat is only latent when it doesn't affect the temperature of the liquid (it's latent because it's 'hidden', like that). The latent heat of evaporation is - pretty much - 'the heat used to turn liquid into gas', rather than heat used to increase the temperature of the liquid. But ignoring that technical distinction, you're spot on. Once the air next to the skin is saturated, no more moisture can be taken up, which means sweat essentially warms up as heat is pumped in, rather than evaporating. Since it's not a closed system in real life there's always likely to be [isome[/i evaporation going on, but the efficiency of cooling is much lower.



Aye, I'm a pedant, though





I can't argue, there.

Well Chev Walker posted this picture on Twitter last week after playing at the KC, showing that it's not just Widnes and Salford ruining players legs! https://twitter.com/#!/chevwalker/statu ... 52/photo/1

Well Chev Walker posted this picture on Twitter last week after playing at the KC, showing that it's not just Widnes and Salford ruining players legs! https://twitter.com/#!/chevwalker/statu ... 52/photo/1

so we've had 3 players sporting "grazed knees" playing at 3 different grounds.......



now..... im no genius but i'd suggest the common factor was the icy conditions not whether the grass was real or plastic

Look, people have made their minds up. The grass needs to go. Widnes and the RFL are idiots/cheats/etc, and the players should speak up in public immediately after any grievance without a care or thought.

The RFL needs to answer why it's allowing games to go ahead in conditions like this.

has'nt it already been said that if the salford game was'nt on sky it would'nt have been played?

Because it's not up to the RFL to decide whether a pitch is playable or not, it's up to the match officials - usually in consultation with both clubs?

Don't the match officials come under the jurisdiction of the RFL?

To be honest, there's no real harm done though, this is a tough sport and i'm sure the players can cope with scraped knees for a few games while the spring gets here!

So what? The book stops with the match officials. If they give the go-ahead, how is it anyone at Red Hall's fault?

Buck.

[urlhttps://twitter.com/#!/matty_ash_89/media/slideshow?url=pic.twitter.com%2FuTZVGGgZ[/url

I don't know if this has already been posted. I can't be bothered looking back through the thread, but looking at Matty Ashursts knees maybe the game at Salford should have been called off!!!

Only been mentioned about 10 times



I didn't know about Dennis Betts telling Richie Mathers to "man up" though after his Twitter pic



And Chev Walker has also tweeted a pic of his knees after playing at the KC the other week in Radford's testimonial. I'm pretty sure the pitch wasn't even frozen that weekend.

Maybe he should tell Ben Cross to "man up" after is teddy throwing and abuse at the Sky camera.

so to sum up 17 pages

'the ipitch is rubbish and causes injury'
'no it doesnt'
'yes it does'
'no it doesnt'
'yes it does'
'no it doesnt'
'yes it does'
'no it doesnt'
'yes it does'
'no it doesnt'
'yes it does'
'no it doesnt'
'yes it does'

There must have been the odd mention of Mathers in there too.

It's been a good few days for knee fetishists, that's foreshore.

No, I'd say it's more a:

'The iPitch causes injuries.'
'We have no idea yet.'
'But it does.'
'But we have no idea yet.'
'Yes we do.'
'No we don't.'

The only discussion has been whether you can judge the effectiveness of a new playing surface after one game in extreme weather conditions. Some people think you can. Others aren't that stupid.

[urlhttp://viewtopic.php?f=15&t=518207&start=10[/url

www.bbc.co.uk/blogs/georgeriley/ ... _egos.html

www.bbc.co.uk/blogs/georgeriley/ ... _egos.html

All I said was that I hadn't heard complaints from players involved in the Halifax/Crusaders game,I never claimed complaints didn't exist.I don't know if any of the anonymous posters in your link are players.