- What is road grit?
- How do road gritters operate?
- Will following a road gritter damage my car?
- What is the safest way to pass a road gritter?
- What if I think a gritter has damaged my car?
- How do I spot a road gritter?
- How advanced are the latest road gritters?
- What about gritting local roads?
- What NOT to do when you see a road gritter
Road gritter spreading salt in winter
Roads are often coated with grit in the winter months to improve grip and reduce the risk of accidents. Gritter trucks travel slowly and you will probably need to overtake at some point. But does passing a road gritter mean inevitable stone chips and damage to your vehicle?
Here’s what you need to know when following a road gritter, including how to pass with maximum safety – and minimal risk to your car’s paintwork and windscreen.
What is road grit?
Close-up of a road gritter spreading salt
Road grit is not actual ‘grit’. Years ago, it was a mix of sand, small stones and salt, but these days, rock salt is used. This is softer and less likely to cause damage than stones. The sound you hear is often the ‘splatter’ of salt, rather than the impact of tiny rocks.
Some local authorities use a product called Thawrox. This is a mixture of rock salt and a food-grade agricultural by-product produced in the sugar refining process. The manufacturer says it offers a smoother flow with less binding, so the spread pattern is more efficient. It also gives less ‘bounce’, so the spread rate can be reduced – also helping lessen the risk of damage to passing cars.
Sometimes, grit is wetted before being spread, so it starts acting on the road surface more quickly. Again, this makes it less likely to damage passing cars.
Rock salt is largely sourced from three huge underground mines in the UK. It is ground away by machines rather than by hand. Before being transported to storage depots, it is treated with an anti-caking agent.
How do road gritters operate?
The most efficient speed for gritting a road is between 40mph and 50mph. Gritters try to stick to this speed, even on motorways. On three-lane carriageways, gritters will drive in the middle lane, so all three lanes can be treated equally.
Usually, when a gritter is spreading salt, its amber lights will be flashing.
Salt spreading is automated and adjusted by speed. When the gritter stops, it will cease spreading salt until it moves again. The equipment at the rear contains an ‘agitator’ to ensure salt is spread as evenly as possible.
Will following a road gritter damage my car?
Road gritter on the motorway
Following a road gritter can be a horrible sensation; it sounds like your paint and windscreen are being chipped to pieces. However, thanks to a combination of the latest road grit and salt spreading technology, it often sounds worse than it is.
If you’re careful about how you follow a gritter, the risk of damage should be minimal. You just need to go about it in the right way.
What is the safest way to pass a road gritter?
The best way to pass a road gritter is to minimise your time exposed to danger. In this case, it’s the spray of salt from the rear of the vehicle. Hang back, out of the way of the road grit, then swiftly overtake when it is safe and clear.
Your objective should be to minimise the clattering noise you hear. If you’re on a single carriageway, leave a clear distance until you pass. On a motorway, do the same, but without ‘lane-hogging’.
On four-lane motorways, gritters will often travel in the second lane. Experienced drivers will travel in the fourth lane with a second car in the third lane acting as a ‘shield’ between them and the road gritter. It’s very satisfying when you manage it…
What if I think a gritter has damaged my car?
The government has a comprehensive online guide for motorists who think their car has been damaged and want to seek compensation. However, it also has a disclaimer: ‘You can’t claim compensation if debris from another vehicle caused the damage. Contact your insurer instead’.
It is unlikely that a claim for chipped paint or a broken windscreen that you believe was caused by a road gritter would be accepted. If you could provide clear evidence, though, such as dashcam footage, it could be worth trying to get compensation.
How do I spot a road gritter?
Road gritter spreading salt on a British road
You would think spotting a road gritter would be easy. Not for some: every year, there are around 40 incidents of people driving into gritters. If the expensive salt-spreading equipment at the rear is damaged, the gritter will be taken out of action.
Following research with the Transport Research Laboratory, Highways England now paints its gritters in one block colour: bright orange. This emphasises the ‘solid’ shape of the vehicle, which the research indicated would help salt spreaders to stand out as much as possible.
How advanced are the latest road gritters?
The latest road gritters used by Highways England are built by Romaquip. They feature technology that allows route information to be pre-programmed using GPS.
This means salt is spread automatically, taking into account bridges, road features and other specific landscape details. It means salt isn’t wasted, drivers can fully concentrate on the road and, theoretically, there’s less risk of ‘stray’ salt being splattered onto cars rather than the road.
The UK’s biggest operator of road gritters is Highways England. It runs more than 500 winter vehicles to cover 4,400 miles of motorways and A-roads.
What about gritting local roads?
Highways England is only responsible for motorways and A-roads; local roads are the responsibility of the council in that area.
If you live in England or Wales, you can find out which roads your council will grit by entering your postcode into a GOV.UK tool.
What NOT to do when you see a road gritter
Remarkably, Highways England says there are a growing number of instances where drivers take to the hard shoulder to avoid a road gritter.
Quite apart from being illegal, this is highly dangerous, as stranded cars could be hidden from view. Also, if the road is untreated, the area most likely to be icy is the unused section of the hard shoulder…
Keyword: How to pass a road gritter without damaging your car