+ Why use salt ?
Salt lowers the melting/freezing point of ice. Normally the point of ice melting is at 0oC (32F). A 10% salt solution lowers the melting point of ice to -6oC and a 20% salt solutions lowers the ice melting point to -16oC
+ Why should I be worried about ice and snow forming?
During winter months, a high number of accidents involve slipping on ice and snow. we will will advise you how to ensure your employees / tennants are safe in these circumstances
+ How do we decide when to grit?
We monitor the weather conditions & forecasts using a variety of information sources
Salt is ideally spread before roads become icy or snow starts to fall.. This is known as precautionary salting. After a sub zero temperature has been forecast we spread the salt ideally in advance of the temperature fall and freezing conditions.
Prevention of ice formation is far better practice than treating already formed ice/fallen snow.
+ When do the salt spreaders go out?
Salt must be spread before the road becomes icy or snow starts to fall. This is known as precautionary salting. After a sub zero temperature has been forecast we spread the salt ideally in advance of the temperature fall. Preventing ice forming is better for the environment than treating already formed ice as less salt is required. This is why you see the gritters on the road during the late afternoon and early evening as well as during the night.
+ What happens when it rains and then immediately freezes?
This is the most difficult situation to orchestrate at the right time as heavy rain will often wash away salt before it has a chance to work. In this instance salt may be spread on already formed ice or snow after the rain has stopped. It will still be effective but means more salt will have to be used to raise the melting point of the ice or snow.
+ Do you use salt spreading for snow clearing?
Gritting while snowing is less effective than having salt on the surface prior to snowing. So we try to get a layer of salt on the road before a snow fall which acts to slow the rate of the snow from settling. The most effective treatment for a snow fall is to move it using the snow ploughs. These are most effective with 75mm of snow or more.
+ Why don’t we grit every night sub zero temperatures are predicted?
Because we are a local independent business we have good local knowledge of the prevailing weather conditions and can react accordingly. Sometimes when a frost is predicted it does not always mean conditions will cause ice to form on roads. There can be enough heat in the ground to keep the roads from freezing. Also if there have been consecutive sub zero nights there might be enough grit/salt on your surfaces already especially if there hasn’t been any rain to wash it or wind to blow it away and the traffic volumes have not been too high. Conversely temperatures can stay above zero, but conditions can allow ice to form.
+ How much salt do we use?
the recommended guidelines are to spread approximately 10-15gms/m2 for precautionary salting and 20-40gms/m2 during ice and snow conditions. Although of course this may differ, as we evaluate each visit on a needs basis.
+ After gritting will our surfaces be 100% safe?
There is no such thing as an absolutely safe surface, although we will do our absolute best to minimize the risk!
+ How does the salt work?
The Salt works by lowering the freezing point of moisture on the surface. Salt can stop ice forming and cause existing ice or snow to melt. However, salt doesn’t work instantly; it needs to be ground down by pedestrian/vehicular traffic in order for it to be activated. Please note this process will take far longer on pedestrian areas than on roads, which is why we endeavour to help the process by using specialist hand tools & spreaders. When the surfaces are dry there may be a white appearance caused by the salt, this will soon disappear. Any residual salt will itself attract moisture and can give the surface a damp appearance, this again is perfectly normal and the salt should prevent the moisture from freezing.
+ How do we know when ice or snow is on the way?
We monitor the weather day and night seven days a week from October to March , we receive weather updates directly from the Met eir and local weather stations. The weather forecast arrives around 1pm each day which allows time to work with clients to make a decision on where to send our gritters in order to spread salt..
+ type of premise do you grit
'irish salt andGritting Service takes over where the local authority stops – when people turn off the public roads into your car park or road. We grit local business parks, retail parks, shopping centres and industrial parks. We also grit driveways, car parks and steps of care homes, hotels, restaurants, public houses plus private roads and health centres. We will grit any public or commercial premises that need to be free of snow and ice in winter.
+ how much will your gritting cost
Before we can supply a quote we first need the address of your premises – contact us>> We are well aware businesses don’t have an unlimited budget for gritting. So when the temperature is likely to be between zero and minus 1 (and it’s debatable if there will be a freeze) we always contact you to give you the option to grit or not. And when the weather is dry and we have gritted on previous nights there could be enough salt down already, so again we would ask whether you want us to grit or not We always take a cost conscious approach to your gritting services and keep you updated at all times. For a free quotation please send us your address via the contact form.
+ what is involved in salt grittiing
We carry out precautionary salting which means salt is spread onto the road surface before the road becomes icy or any snow starts to fall. The salt is evenly distributed for maximum effect. We can also grit building steps if required too
+ snow
When snow is forecast salt is spread on the roads to slow the rate of snow settling. Salt alone has very little effect on snow. Once the snow is about about 25mm or 1 inch it is deep enough to plough
+ Weather forecasting and decision making
The Meteorological Office provides us with weather forecasts which include road surface temperature information. The forecasts form part of our Ice Prediction System, the system is monitored 24 hours a day throughout the winter and gives the Winter Maintenance Duty Officers the latest weather information as well as actual road surface temperatures and other information from various sensor sites. This information enables the Duty Officers to make their operational decisions. Precautionary salting is carried out when there is a clear probability of ice or snow, in that wet road surfaces are expected to fall to or below 0º Celsius.
The Ice Prediction System allows the Duty Officer to make a more accurate assessment of the need for salting - this results in a reduction of the risk of failing to salt when required but also provides a saving in costs since the number of unnecessary road salting is reduce
+ How can we get it wrong?
No matter how accurate the forecast, there are situations where we cannot salt the network prior to icy conditions. Such situations are:
When rain is followed by rapidly clearing skies, salting will normally start after the rain has stopped (to avoid the salt being washed away). Sometimes temperatures may fall by as much as 5°C per hour and the wet roads may well freeze before we have been able to salt them.
'Dawn frost' occurs on dry roads, when early morning dew develops, falls on a cold road, and freezes on impact. It is impossible to forecast with any accuracy where and when this will occur.
Rush hour snowfall. When rain turns to snow coinciding with the rush hour, early salting cannot take place as it would be washed away and gritters cannot make progress due to traffic congestion.
We will, however, always carry out salting to remove ice. This is not ideal and salt takes longer to act once ice has formed.
+ Rocksalt
We use rocksalt and coated rocksalt as our anti-icing materials. Our gritting fleet spreads salt onto the highway at spread rates between 8 and 40gm/square metre depending on road surface conditions. 8 or 10gm/square metre is normally spread when we expect ice, and 40gm/square metre when we are trying to clear a build up of snow and/or ice. We need to spread salt accurately as it comes from a non-renewable source and in high concentrations, is environmentally unfriendly and can damage vegetation.
Salt works by turning the ice or snow surrounding each granule into a saline solution. The action of traffic is essential for salting to be effective by breaking down the salt granules to form a saline solution to either prevent ice from forming or to melt it
+ Why is it better to grit in advance of bad weather rather than after it has happened?
It is extremely important that gritting is used as a preventative method to avoid ice forming as it cannot be used as a reactive solution to icy weather. This is for the following reason: water freezes at 0c; when gritting is carried out the salt molecules connect with the water molecules, which make it more difficult for ice to form. The result of this is that a solution is formed that has a much lower freezing point than water – hence preventing ice forming.
Once ice has already formed, grit simply sits on top of the ice and the salt molecules are not able to connect with the water molecules to form the solution with the lower freezing point.
+ What type of grit / salt is used and why?
we only spread white fine grade salt. This ensures that any salt carried through from the car parks, pathways and public areas does not damage or stain the flooring of internal buildings.
White salt is more expensive than standard brown salt that may be used by other companies, but if you take into account the cost of cleaning and repair to damaged flooring that the use of brown salt may create, white salt is a more cost effective option. Dirty, damaged flooring is also bad for business, creating a poor impression to visitors and clients.
+ How much grit/salt is used?
Grit is used as required. Our highly accurate localised weather forecasts ensure that gritting is only carried out when necessary.
We also use specialist calibrated drop spreaders which make sure the amount of grit sprayed is adequate without being wasteful. This avoids damage to the environment and higher gritting bills
+ What happens when there are multiple days of bad weather?
Each and every day during the winter months, we receive highly localised weather forecasts for each site location that has an Ice Watch contract. This is then analysed by the Operations Manager who makes an informed decision based on the ground temperature and moisture levels. This is assessed on a daily basis to ensure that each car park, pathway and public space is gritted as necessary each day.
Our expert services mean that even when there are multiple days of bad weather, ice is prevented from forming.
+ Once gritting has been carried out, is the ground fully safe to walk on?
Whilst our services do enhance the safety of the car parks, pathways and public areas it is also the responsibility of the individual to ensure that they take care in icy conditions
+ Can the weather always be predicted accurately?
There are occasions when the temperature and ground moisture are borderline and we cannot be certain of ground frost or ice. On these occasions we send our operators out to do free on site inspections to ascertain the need for gritting. They will then use their expert knowledge to make the decision as to whether gritting is necessary
+ What equipment is used for car park gritting?
We use specialist calibrated spreaders that precisely determine the amount of grit that is required. This avoids waste, unnecessary costs and damage to the local environment
