As snow and ice professionals prepare for the upcoming winter, thoughts of the last season of snow and ice won’t be far from mind. With heavy snow accumulations across the North and frigid temperatures that plunged into the Deep South, last winter taught us that preparing for all conditions is the best way to ensure your snow and ice control measures will be equal to the task this season.
Pre-season equipment inspection and maintenance, crew training, and a comprehensive plan for proper response to storm events are all essentials. But just as important are selection of a deicer capable of quickly and reliably melting ice under the wide variety of conditions you are likely to face, and ensuring that the material will be available when you need it throughout the winter.
What to look for in an ice melter
With a range of products to choose from, and often misleading product labeling to contend with, choosing the most effective ice melter can appear complicated. It really isn’t when you remember a few basics.
Although several performance characteristics can guide selection of a deicer, two are particularly important:
- How reliably will the material perform across all winter conditions, so you can confidently use one product regardless of how unpredictable the weather becomes?
- How quickly will the material melt ice, so you can minimize pedestrian exposure to dangerous conditions and save crew time and expense?
To evaluate the performance of deicers against these two parameters it helps to understand that, for ice to melt, solid ice melter must dissolve in water to lower its freeze point and create brine. Even though it may not be visible, molecular water is always present on the surface of ice. The amount of water is higher when temperatures are warmer and is reduced at colder temperatures. That’s why melting is slow when some solid deicers are applied to ice at colder temperatures.
For greatest effectiveness throughout the full range of winter conditions you need a deicer that dissolves quickly, even at colder temperatures when conditions are driest.
Effective deicers share two properties:
- They attract water. Because the surface of ice isn’t very wet, a deicer should take maximum advantage of all the moisture it can. Materials that attract water are called “hygroscopic”. They attract any available moisture from the surface of ice and the surrounding air so they can begin to dissolve under any temperature conditions.
- They release heat. To further speed ice melting, ice melters should release significant heat as they dissolve. Materials that release heat are called “exothermic” and melt ice more quickly and reliably across a wider temperature range than “endothermic” ice melters, which depend on heat from their surroundings to create moisture necessary for them to dissolve. Among common deicers, calcium chloride is a highly exothermic material – it can raise the temperature of a gallon of water by over 30°F (17°C)!
These two properties account for the difference in the ice melting ranges of common deicers, which are shown in the accompanying chart. Note that calcium chloride, a highly hygroscopic and exothermic ice melter, will melt ice under a far broader range of winter conditions than other ice melters, making it a highly reliable deicer under the most unpredictable winter conditions.
Examine the content of blended deicers carefully
The melting ranges shown here are for full-strength deicers and not blended products. Despite what the packaging claims may suggest, almost all blends consist predominantly of rock salt or other relatively low cost material with only a small amount of a high performance deicer. These products won’t perform better than the base material alone. For example, a blend should contain at least 20 percent calcium chloride to offer a noticeable improvement in melting temperature range and melting speed greater than the base material. Even at a level of 20 percent calcium chloride, the material won’t match the melting range and speed of full-strength commercial products, such as OxyChem products containing from 83 percent to 90 percent calcium chloride.
Make sure your supplier can deliver
Understanding which deicer will work most effectively is important, but equally important is knowing that the deicer you need will be available to you all winter long. Snow and ice professionals can protect themselves from potential product shortages by doing some homework in the off-season. Start by assessing the performance of distributors who supplied ice melter in the past.
Ask the right questions
Do they offer the right deicer? As we’ve described, ice melter performance can vary significantly, which can have a direct impact on how well you can control ice. Your distributor should offer a deicer product capable of melting ice efficiently, effectively and reliably under the full range of conditions you will face. Make sure product contents are clearly stated on the product label and be wary of products that don’t provide a detailed list of ingredients including the percentage of total content of each ingredient. Supporting product documentation should always be made available to you. Also confirm that the product you need is available in the right packaging.
Do they maintain adequate inventories? Ask what they do to anticipate needs in the local market. How do they plan initial orders from the manufacturer? How much inventory do they maintain nearby? What lead time do they build into their reorder process during the course of the winter? Some distributors may allow supplies to become depleted in the late winter to avoid carrying product over the summer, but that won’t help you in the event winter conditions persist into early spring. Ask if they maintain late winter inventory levels to ensure ice melter is available if your area is hit by late season storms. You can do your part to help your distributor plan inventories by discussing your anticipated needs in advance and monitoring your own inventory throughout the winter, allowing adequate lead time when reordering.
What is the manufacturers’ track record? Your distributor’s ability to fulfill its promises depends heavily on the performance and commitment of the ice melter manufacturer. Snow and ice professionals should discuss manufacturer capabilities openly with distributors. Is their partnership strong, or untested? Are you and your distributor likely to be at the mercy of an unreliable manufacturer when the going gets tough? Your reputation for reliability with your own customers is at stake, so it makes sense to research the capabilities of manufacturers independently as well. Look for evidence that manufacturers have made significant investments in pre-season inventory and have proven their ability to deliver in-season, when reliability and service matter most.
Where does the raw material originate? A manufacturer’s access to raw materials can make the difference between reliable winter-long supply and a shortage when you can least afford it. During a harsh winter when demand is high, domestic producers with integrated raw material capabilities – and shorter supply chains – are better equipped to supply your needs than those who rely on bulk shipments of raw materials from offshore suppliers. A manufacturer that combines large-scale domestic production capacity with multiple ship points will be better equipped to meet your needs no matter what winter brings.
Can they help improve how you melt ice? Knowledgeable distributors are a source of valuable information that can help you better protect your customers from the risk of costly slip and fall accidents while also improving how you melt snow and ice. Ask distributors to share ice melting best practices that can help you save time and money. Also ask how you can use deicer products more responsibly, to reduce impact on property and the environment without sacrificing performance. You can take matters into your own hands by independently visiting www.IceFreeSidewalks.com, a website developed by OxyChem to help snow and ice professionals, facility managers and others improve ice melting practices.
The winter of 2013-14 reminded everyone how harsh and uncertain winter conditions can be. To prepare for the 2014-15 winter season, start by choosing a reliable, high performance ice melter, then make certain the material will be available to you all winter long. By paying close attention to these basics, you’ll be confident you have the right deicer and the right supply partner to take on whatever winter may bring.
About the Author
Greg MacDonnell is general manager with Occidental Chemical Corporation (OxyChem). He is responsible for calcium chloride sales, marketing and business management. His 25 year career in the chemical industry includes 15 years specializing in calcium chloride.