ANTI-ICING
Anti-icing is the practice of applying ice melting chemicals before or at the start of freezing precipitation to prevent the formation of ice-to-pavement bonds. Compared to deicing after weather events, anti-icing requires considerably smaller amounts of ice melter material, reducing material and application costs, as well as potential runoff to the environment.
LIQUIDOW™ Calcium Chloride Solution alone or in enhanced liquid blends, or salt prewetted with LIQUIDOWTM, may be used for anti-icing. The decision to use one of these approaches depends on many factors, including available equipment, pavement temperatures, and current and expected weather conditions. For guidance in implementing chemical anti-icing applications, Report 577 of The Transportation Research Board, National Cooperative Highway Research Program (NCHRP) cites two sets of recommendations as detailed below.1 These rates are based on the equivelant amount of dry solids applied at temperatures from 15°F to 32°F (-10°C to 0°C).
Typical Chemical Application Rates for Anti-icing Activities at 15°F to 32°F (-10°C to 0°C)
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Dry Chemical spread rate, kg/lane-km (lb/lane-mi)
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Reference
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Light icing
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Light snow
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Heavy snow
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Freezing rain
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“Manual of Practice for Effective Anti-Icing Program”FHWA/CRREL
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7-36
(25-130) |
28-55
(100-200) |
28-55
(100-200) |
21-110
(75-400) |
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“Manual of Practice for Anti-Icing of Local Roads” New Hampshire T2
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18-36
(65-130) |
28-55
(100-200) |
28-55
(100-500) |
21-110
(75-400) |
1 Transportation Research Board, National Cooperative Highway Research Program (NCHRP), Report 577, 2007