Safe Speed Forums

Safe Speed issued the following PR at 16:54 this afternoon:

PR288: Molasses eliminated, but low road grip remains a mystery

news: for immediate release

The mystery of low - probably dangerously low - road grip levels continues.

Investigations reveal that widespread reported low road grip CANNOT be caused
by molasses added to de-icer treatments. However reports of low road grip
continue and concern remains high.

At this stage the evidence is largely anecdotal, although one report received
confidentially points to the lowest dry grip ever recorded (in one specific
location).

Rainfall has been reported to increase grip levels and more changeable weather
in the past week has apparently increased grip in a number of areas.

Paul Smith, founder of the Safe Speed road safety campaign
(www.safespeed.org.uk) said: "Widespread reports of low grip conditions remain
a serious issue of public safety. Recent information means that we can
effectively eliminate molasses, but the cause remains a mystery. It is both
urgent and important that an investigation is carried out to determine the
true cause of exceptional and dangerous conditions."

Mark Dutton, Managing Director of Safecote Limited (www.safecote.com) kindly
provided the following statement: "Safecote is NOT used as a neat product
anywhere in the UK. It is used as an additive to de-icing salt at the rate of
only 3% by weight. This type of de-icing product is being used on less than
5% of the UK's highways and the Transport Research Laboratory has fully tested
the skid resistance properties of normal rock salt versus rock salt with 3% of
Safecote and no difference was detected. This report is downloadable on our
web site."

What we do know:

* Exceptionally low road grip has been reported in many areas

* The only molasses treatment is 'Safecote', and Safecote has been applied to
less than 5% of roads this winter.

* Widespread reports of low grip CANNOT be caused by the use of molasses
because low grip has been reported in many areas where molasses hasn't been
used.

* Reports suggest that grip improves after rain.

* There is an apparent association between the low grip reports and a long dry
spell.

<ends>

_________________
Paul Smith
Our scrap speed cameras petition got over 28,000 sigs
The Safe Speed campaign demands a return to intelligent road safety

In front of, and behind many traffic islands in this area, are large areas of salt/grit which have not been crushed or spread.
Could the lack of rain on unused salt be a possible answer?
Anyone understand the physics of "salt" and tarmac?

_________________
Time to take responsibility for our actions.. and don't be afraid of speaking out!

I know that there used to be a problem called marbleling, where the lumps of salt could become rounded like marbles. This had an effect similar to that when a child had left their marbles on the floor and an unsuspecting person stepped on them, resulting in a momentary and often painful loss of friction. I understood that this problem had been eliminated, but this might be a clue, especially with the roads and the air being so dry recently.

Interesting, surely this can be fairly easily checked by the TRL? Must be a lot of factors involved though, from weather conditions to tyre wear on individual cars - probably needs proper scientific study rather than "anecdotal evidence".

As an aside, that PR was a bit dodgy to say the least. Publishing a statement about safecoat without any checks and then issuing what was effectively a retraction makes you look a bit amateur (which is a shame, because you seem anything but).
Also, one comment on the forum about the grip seeming to improve after the rain doesn't really equate to "reports" - I haven't noticed anything wrong with the grip around here, does that mean "reports indicate that Bedfordshire appears to be immune from the low grip problem"?

The road crown, and behind islands around us are positively PINK with grit/salt which has not been dissolved or crushed, and is just loose on the surface.
I have been waiting for a safe opportunity to drive onto it and check for grip - but none has presented itself yet.
Perhaps Ian H might help out!!

_________________
Time to take responsibility for our actions.. and don't be afraid of speaking out!

"I haven't noticed anything wrong with the grip around here, does that mean "reports indicate that Bedfordshire appears to be immune from the low grip problem"?"
I have in Kempston. Hillgrounds road in particular has been exceptionally black and slippy, even while attempting to walk across it.Whilst the cul de sac ,which hasn't been salted, that I live on, which comes out onto Hillgrounds, is perfectly normal once the sun has cleared the frost.

Ah, in that case then i'll make it "Bedfordshire Motorists divided over alleged low-grip problem"

On a more serious note, I have been thinking about this a bit since my original post. We have had a new surface put on the exit road from my place of work (shiney new black tarmac, not the cruddy pebbles) and it has recently been gritted for the first time. There is now a very clear lighter-toned patch running down the centre of each side (from car wheels), but it is still black at the edges and the middle. Surely, anything that remains on the road surface between the surface and the tyre MUST reduce the contact friction? (unless its superglue).

I can feel a stopping experiment coming on... (roads on site also resurfaced but not gritted).