Sandberg can undertake the testing of salt for spreading on highways for winter maintenance using the methods given in British Standard BS 3247:2011+A1:2016. Sandberg holds a UKAS accreditation to undertake salt analysis.
About Rock Salt
Every winter, following a snow episode, our roads and highways need to be quickly cleared to allow people to carry on with their normal daily activities. This is most easily achieved by a combination of physically removing the snow with snow ploughs etc and/or spreading salt onto the highways. Additionally, with the aid of modern long term weather forecasts, those charged with keeping the roads clear can deploy the salt in advance of any periods of freezing weather or snowfall. Salt is at its most effective when it is applied before a freezing episode because it can prevent snow or ice from hard packing.
There are three main types of salt used for winter road maintenance:
- Rock salt – derived by mining natural salt beds
- Vacuum salt – salt prepared by the evaporation under vacuum of brine
- Marine salt – derived by solar evaporation of seawater
All types of salt work by depressing the freezing point of water. The particle size distribution of the salt is also an important factor as this will govern the spread of the salt from the height of the salt distribution. If the salt particles are too fine, with spreading machines conforming to BS 1622 with a height distribution of 300-350mm above the surface of the road, the particle velocity may not be sufficient to give a wide spread on one pass. Similarly, with particles that are too large, they may be spread too widely and end up on the verge of the road.
All salt for spreading on highways for winter maintenance is covered by the British Standard BS 3247:2011+A1:2016.
For more information contact our in-house expert:
