There's a lot that goes into the daily grit, from start to finish - here's a look at the processes, science and tech that drives your winter gritting.
During autumn, planned gritting visits for the forthcoming winter season are programmed for each client and all their sites into our work planning and job control platform, NIMBUS. The parameters include key contract requirements such as access, gritting density, and the designated areas.
Daily road surface temperature (RST) forecasts are provided by MetDesk at mid-day. Visits are triggered when the forecasted RST for that area meets or drops below the agreed value, typically 0 degrees Celsius. Jobs are then dispatched to the operators’ smartphone work tool for each shift, providing service-specific information for the operator to use, as programmed in on NIMBUS. Via their smartphone, operators confirm they are on-route, arrival on-site, and after gaining access, commence their work. All job and travel data is recorded and held on NIMBUS, and provided as a daily post-completion report to our clients the following morning after 6 am.
The daily grit
GRITIT™ always uses the same teams on the same sites to ensure our operators build familiarity with your site. We utilise BOSS salt spreaders directly attached to the vehicle or trailer towed; these spreaders are usually loaded prior to arrival and topped up on-site. Salt stocks are stored on many customer sites. White marine salt is used, conforming to BS 3247:1991 standards and requiring less spread for a highly efficient grit.
For precautionary gritting, we will apply salt evenly at 40 gsm. (grams per square metre). 15-40 gsm of salt is required for efficacy, as well as cost and to minimise any environmental impact. For precautionary gritting to be effective is imperative that this is carried out prior to any ice, snow or frozen conditions. In our experience, when attempting to treat ice after the event we typically use between four and ten times the amount of salt rather than when applied before the event. To achieve optimum efficiency, we:
- Calibrate machinery correctly, checked and tested on a regular basis. We use purpose built spreading equipment, manufactured for spreading salt only. Latest UK guidelines will allow a 1.5% tolerance or deviation on correctly calibrated equipment.
- Ensure driving speeds are correct during spreading. Driving at the wrong speed will impact on spread rates. Our spreaders are controlled by the operator from the cabin with the ability to increase output, (spin and auger) in conjunction with speed. This is controlled from within the vehicle.
- Use the right salt. Any material that does not meet the appropriate British standards will again cause problems. The standard includes: moisture content – acceptable for Marine Salt 1.5 – 4%, for rock salt 2-3%.
- Undertake spreading at the right time. Spreading after the weather will result in unnecessary exposure to risk, but also the need to spread more salt than required. (The chemical reaction for salt to lower the freezing point of water requires some time to activate/ meaning the salt must be applied wherever possible with enough time to ‘dissolve’ into a saline solution to be effective. In an ideal world a 2-hour window is optimum.
- We consider, drain or run off areas, as well as traffic times; these all impact the end result.
Gritting walkways clinically by hand
Walkways are best manually serviced by bucket and scoop or push spreader with deflectors or quad bike with drop spreader, with the salt aimed to be more concentrated to the middle of the walkway and edges with a lesser amount to reduce the risk of salt on the grass. Again, white marine salt, conforming to BS 3247:1991 is used, to minimise residue that comes inside.
Spread rates for treating pedestrian areas are the same as vehicle-delivered mechanical gritting. In our experience it is more efficient, effective and clinical when someone takes care of it by hand using a bucket and scoop. The alternative is a pedestrian spreader which will almost certainly cause damage to planted areas as the spread rate is typically more than 1.2m wide, far more than what we need. Operators always ensure that all walkways are gritted appropriately; this involves getting out of the vehicle and walking every walkway on every site. Doing this operation by hand ensures:
- We inspect all areas of the site and ensure salt is applied correctly to all areas.
- Marine salt as opposed to rock-salt, once ‘dissolved’ leaves minimal residue.
- Spread rates may vary slightly; the important point is we get material to concentrated and critical areas of the site where a pedestrian accident could occur.
The typical daily grit timeline
- 16:35 - Job dispatch list is completed and verified
- 18:00 - Response received for all operators to confirm receipt of nights service list on their smartphone
- 18:05 - Investigate any operators that have failed to respond.
- 18:00 - 06:00 Operators commence service delivery and job completion is monitored on a live basis and service data returned to us in real time as the jobs are completed, with any issues being reported to site on a live basis
- 22:00 - Inspection lists dispatched to assistant regional managers to conduct site checks
- 02:00 - Site checks completed, and data returned to us
- 09:00 - Service reports emailed to client sites
Extra gritting, as and when you want it
Once on-site, operators deliver reactive gritting maintenance using the same procedures as our planned gritting visit. Any clients can contact our UK-based 24/7 help desk to log an additional visit request. They can log a job directly into the website or call us on our 24/7 number. Our call handlers log requests into our contract management system NIMBUS which pushes this directly to our operations teams and the operator’s smartphone. The service is delivered within the service level agreement time agreed.
Snow & ice clearance when it's warranted
Snow & ice clearance operates to the following activation criteria based on either the existing weather conditions or forecast conditions as provided by MetDesk. We undertake snow or ice clearance to pedestrian areas (walkways etc) when ice or 2 cm+ of snow is present at the time of the gritting visit. This applies to key pedestrian walkways, to and from car parks, and fire exits. It is typically undertaken manually using a snowplough. Our operators are highly trained, to:
- Check that the pedestrian snowplough is in good working order before use.
- Assess the site and site plan - ensure all areas in dark blue are cleared of snow and gritted afterwards.
- Take care when using plough near corner and uneven surfaces as the plough may get snagged.
- Always remember to push snow away from doors, fire exits or stairs.
- Always clear a safe path from the main entrance to the car park.
- Ensure that all fire exits are cleared weather they are marked in dark blue on the service plan or not.
- Dress warmly and ensure they wear the correct personal protection equipment (i.e. bright yellow PPE) to be visible to site traffic.
Mechanical snow clearance is delivered by a specialist and separate fleet to that used for gritting. We use a fleet of 4x4 pick-up vehicles or JCB-type vehicle fitted with a bucket or scoop for high volume snow clearance, dependent on the volume of snow fall. Snow clearance is automatically scheduled when snow is forecast to fall between 12:00 noon and 06:00 am the following morning. Snow clearance is scheduled to commence toward the end of a snow event.
Our standard service trigger is 5 cm+ of snow forecast. Our current forecast model includes highly detailed and location-specific weather forecasts bespoke to our service requirements for over 450 individual weather locations. It has been tailored specifically to give a clear indication of snow risk throughout the country considering location, urbanisation, elevation and the constant push and pull of relevant frontal weather systems surrounding the UK.
Contact us for more information
The extremes of recent years have demonstrated the unpredictability of winter weather in the UK. If you're responsible for a portfolio of buildings, facilities, business or retail parks, this can make it challenging to budget for the costs of winter services. At GRITIT™, we offer a breadth of commercial arrangements with the flexibility to meet the needs of your business. Pay for gritting and/or snow clearance only when needed with a cost per visit (CPV) arrangement that ensures you only pay when the weather conditions trigger a visit. For more cost predictability, fixed price deals for the winter are ideal and ensure peace of mind that no matter how harsh the winter, you will only pay the agreed price.
This covers all visits for winter gritting and/or snow clearance when the agreed weather condition trigger is reached. For clients seeking a hybrid model that combines elements of both arrangements we can create a tailored commercial plan. We can also work with you to customize the triggers for visits according to the exact temperature or snow conditions that meet your requirements – and advise on best practice for doing so while keeping your sites safe.