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High volumes of salt are often applied because contractors, property managers, and parking lot users feel that the more salt there is, the safer the surface is to walk or drive on. However, a surface that has been treated at an appropriate rate, (which is slightly wet with a small amount of salt residue) has a much higher friction value (μ); with the level of service achieved far more efficiently, than when compared to the same surface where rock salt has been heavily applied (over salted).
High volumes of salt are often applied because contractors, property managers, and parking lot users feel that the more salt there is, the safer the surface is to walk or drive on. However, a surface that has been treated at an appropriate rate, (which is slightly wet with a small amount of salt residue) has a much higher friction value (μ); with the level of service achieved far more efficiently, than when compared to the same surface where rock salt has been heavily applied (over salted).
[[File:(3)Measuring friction LSRCA office.png|thumb|500px|The picture above shows the same walkway where more than 10 times the generally recommended amount of salt was applied in the photo on the left, and only shoveling was done in the photo on the right, and both µ values were in the low 0.20s.]]
[[File:(3)Measuring friction LSRCA office.png|thumb|500px|The picture above shows the same walkway where more than 10 times the generally recommended amount of salt was applied in the photo on the left, and only shoveling was done in the photo on the right, and both µ values were in the low 0.20s.]]
Through this work, as referenced above - LSRCA staff documented higher friction values on untreated surfaces than on surfaces with large volumes of product; the µ value of a surface may remain low if it has only been shoveled or plowed. While shoveling is an important part of the winter maintenance process, practitioners need to consider the site and predicted conditions on a day-to-day basis to determine how to attain the safest surface for vehicle and foot traffic. In many cases the sun or traffic may melt the residual snow on a shoveled or plowed surface without any further treatment being necessary (saving both time and money); while in other cases, some salt, applied at an appropriate rate, may be necessary.
Through this work, as referenced above - LSRCA staff documented higher friction values on untreated surfaces than on surfaces with large volumes of product; the µ value of a surface may remain low if it has only been shoveled or plowed. While shoveling is an important part of the winter maintenance process, practitioners need to consider the site and predicted conditions on a day-to-day basis to determine how to attain the safest surface for vehicle and foot traffic. In many cases the sun or traffic may melt the residual snow on a shoveled or plowed surface without any further treatment being necessary (saving both time and money); while in other cases, some salt, applied at an appropriate rate, may be necessary.
====Higher Costs, Little Benefit====
Friction testing has demonstrated that bare pavement is safest, as it has the highest friction value, and that the over-application of salt does not always translate to safer conditions. Simply put, applying salt at the prescribed rate for the conditions and shoveling or plowing where appropriate will attain a higher friction rate than an overapplication of salt.
''What is a reasonable amount of time to achieve the desired level of service?'':
*Depending on the operating hours of the property being maintained, it may be possible to reduce the salt application rate without sacrificing the desired level of service.
**For example, many commercial properties keep hours between 9:00 am and 9:00 pm, which would mean that the lot does not need to be clear until shortly before 9:00 am. The table below demonstrates the time it would take to reach bare pavement at typical industry-recommended application rates, in a situation where the temperature is between -7 and -9 °C, with between 0.5 and 1.5 cm of snow on the ground. The rate may need to be increased or decreased slightly to achieve the desired level of service depending on varying factors related to traffic, sunlight, type of snow, and/or pavement type.
==External links==
==External links==
*[http://www.smartaboutsalt.com/ Smart about Salt]
*[http://www.smartaboutsalt.com/ Smart about Salt]
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