Frequently Asked Questions

There are many claims made about deicing products but separating misinformation from the facts can be difficult. Following are some of the frequently asked questions we receive about ice melting products, and factual answers that help dispel myths and make it easier to make informed choices.* For answers to general questions, see more FAQs on the OxyChem calcium chloride website. 

Will deicing with calcium chloride products damage my concrete?
How does the corrosiveness of calcium chloride compare to that of other deicers?
What are the deicing application guidelines for OxyChem calcium chloride products?
Are calcium chloride-based deicers “pet-friendly”?
Can liquid calcium chloride be used to deice sidewalks and parking lots?
How do I make solutions by mixing solid calcium chloride products with water?
I have used ice melter to remove ice dams on my roof. Are there any concerns about using calcium chloride in this manner?
How can slipperiness be prevented when slush, snow melt and residual deicer are tracked onto hard surfaces of indoor flooring?
What are the recommendations for cleaning carpets that have been tracked with dirt, grime and residual deicer?
Is it okay to use calcium chloride on stone surfaces?
Can damage result from corrosion of rebar when chloride-based deicers are used on concrete structures, such as bridges and parking garages?
Is it okay to use calcium chloride products for deicing wood surfaces?
How should packages of solid calcium chloride be stored?
What materials of construction are recommended for storing liquid calcium chloride solutions?
Can solid calcium chloride that has caked be made usable again?
Is calcium chloride safe for use near grassy areas and other vegetation?

 

Q: Will deicing with calcium chloride products damage my concrete?

A: OxyChem calcium chloride products are recommended for deicing asphalt and concrete surfaces that have been designed and constructed for winter weather conditions and deicer usage. OxyChem calcium chloride products will not chemically attack asphalt or concrete.

Melt water from the deicing process may soak into porous concrete and re-freeze, creating pressure within the concrete structure. Concrete that lacks strength to withstand this pressure may spall or scale. Concrete is resistant to scaling damage if it is air-entrained, mixed, placed and cured according to the recommendations of the American Concrete Institute Committee 201.

OxyChem calcium chloride products are not recommended for deicing concrete that is less than one year old, precast steps, masonry (stone, brick, mortar joints), or existing concrete that has exposed aggregate, is precast, prestressed, chipped, cracked, spalled or weathered.

MgCl2 and Concrete — Don't be Misled

 

Q: How does the corrosiveness of calcium chloride compare to that of other deicers?

A: Because corrosion is a very complex issue, very few simple answers are accurate across all real-world situations. One of the few generalizations that can be made is that common types of bare metal exposed to chloride typically experience an increased rate of corrosion. In general, there is little difference in corrosion performance between the various chloride-based deicers, including rock salt (sodium chloride), magnesium chloride and calcium chloride.

Some vendors may cite a particular lab test to support claims that one chloride-based deicer product is “less corrosive” than another. However, lab tests often fail to accurately represent real-world performance. Good science does not support attempts to differentiate the corrosion performance of one chloride-based deicer versus another.

Non-chloride deicers are less corrosive than chloride-based deicers. However, their deicing performance is relatively weak and there are certain situations where even these expensive products can be associated with corrosion problems.

Deicer Blends and the Environment — Don't be Misled

 

Q: What are the deicing application guidelines for OxyChem calcium chloride products?

A: For best results, plow or shovel snow accumulations prior to spreading calcium chloride. Spread evenly using a cup, scoop or spreader to apply. Since calcium chloride is more effective than other ice melters, use only ¼ to ½ cup per square yard. A 50 lb bag should cover 1,750 to 3,500 square feet. Remove melted ice/snow slush.

Apply shortly after snow begins to facilitate easy removal of snow and prevent ice buildup. Removal of thick ice may require higher application rates to penetrate and undercut the ice layer.

OxyChem calcium chloride products are not recommended for deicing concrete that is less than one year old, precast steps, masonry (stone, brick, mortar joints), or existing concrete that has exposed aggregate, is precast, prestressed, chipped, cracked, spalled or weathered.

Calcium chloride is also not recommended for deicing surfaces composed of wood or metal. Avoid contact with leather products. Use walkout mats to avoid tracking snowmelt, slush, or any residual deicer onto interior floors made of hardwood, tile, stone, linoleum or other hard surfaces as these surfaces may become slippery when wet. Avoid exceeding recommended application rates because interference with traction or footing may result.

For additional information, carefully read the entire product label.

BACK TO TOP

 

Q: Are calcium chloride-based deicers “pet-friendly”?

A: Please review the OxyChem document, Use of Chloride Deicers Around Pets.

 

Q: Can liquid calcium chloride be used to deice sidewalks and parking lots?

A: Yes. However, liquid deicers have significantly less melt capacity than solid deicers because the liquids are already diluted with water. This makes liquids best suited for use in anti-icing or pre-wetting applications, but they can be used for deicing thin layers of snow or ice as well.

The most common liquid calcium chloride concentration used in winter applications is 32%. Solutions this strength can be purchased direct from a LIQUIDOW™ distributor or by dissolving solid calcium chloride products in water. Instructions for preparing solutions of calcium chloride using solid products are provided below.

The most appropriate liquid application rate depends on a variety of situation-specific factors, including weather conditions, surface type, amount of snow/ice present, etc. Over-application or application onto a contaminated surface may result in slickness. If a liquid deicer is applied to a surface under humid conditions prior to a winter storm event, it may absorb enough moisture from the air to dilute to a concentration that will freeze as the temperature drops, possibly resulting in slickness. Because conditions that affect application rate vary significantly from situation to situation, it is the responsibility of each end user to determine the liquid application rate best suited for the particular situation.

 

Q: How do I make solutions by mixing solid calcium chloride products with water?

A: Use cool water when creating solutions. Significant heat is released when dissolving solid calcium chloride. Add solid calcium chloride slowly while continuously mixing. If solids are allowed to sit motionless while in contact with water, a hard cake will form that will be slow to dissolve.

When solid calcium chloride is dissolved, a temperature increase will occur and will vary depending on the conditions associated with each specific application. For example, when dissolving DOWFLAKE™ Xtra 83-87% Calcium Chloride Flakes, assume a temperature increase of 2.8°F per percentage increase in concentration. When making up a 30% solution, the temperature can be expected to increase approximately 84°F (30 x 2.8°F = 84°F).

Use our helpful Making Solutions Calculator tool to determine the amount of dry calcium chloride to mix with water to achieve solutions of various concentrations.

BACK TO TOP

 

Q: I have used ice melter to remove ice dams on my roof. Are there any concerns about using calcium chloride in this manner?

A: First, let’s define an ice dam. An ice dam is a ridge of ice that forms at the edge of a roof and prevents water produced by melting snow from draining off the roof. With nowhere to go, the water backs up behind the dam and could potentially leak into a home and cause damage to walls, ceilings, insulation and other areas.

Preventing potentially serious and costly damage due to ice dams that have already formed on a roof requires two actions: (1) Reduce the amount of snow on the roof, because the snow provides the source of moisture and also insulates the ice dams from melting. (2) Make channels through the ice dams to allow any water behind the dam to effectively drain off the roof.

OxyChem recommends that you hire a trained professional to treat ice dam-related problems and investigate insulation and attic ventilation best practices that may prevent ice dams.

There are ice melt products on the market designed to be thrown onto the roof where ice dams have built-up to create channels that allow melting snow to drain off the roof. Most common ice melt products contain chlorides, including hygroscopic (moisture attracting) products like calcium chloride and magnesium chloride. While very effective in melting ice, hygroscopic ice melt products may cause water to evaporate at a slower rate and remain damp longer than naturally melting water.

If you use ice melt products on your roof, be aware of the risks involved and take precautions to maintain proper drainage. Water from melting ice can corrode roofing nails and steel gutters, and could get under shingles, potentially damaging wood products. You should also prevent the water from draining directly onto vegetation, including shrubs, bushes and evergreens.

 

Q: How can slipperiness be prevented when slush, snow melt and residual deicer are tracked onto hard surfaces of indoor flooring?

A: Always follow the directions on the product label for proper deicer use. Do not over-apply deicer, especially near entryways. Use effective entrance mats that absorb and trap snowmelt, slush or residual deicer. If residual deicer is tracked onto hard floors, it should be cleaned up with warm, fresh water as soon as possible. For example, soak a mop or towel in fresh water, wipe the surface and dry thoroughly. If a bucket is used for rinsing the mop or towel, the water in the bucket should be changed out frequently for best results.

For additional information, see Deicer Tracking and the Indoor Slipperiness Issue.

 

Q: What are the recommendations for cleaning carpets that have been tracked with dirt, grime and residual deicer?

A: Proper procedures for the clean-up of deicers that have been tracked onto carpets include a multi-step process that removes both the deicer and any dirt or oils that have also been tracked in and deposited on the carpet. The majority of experts recommend a cleaning procedure that includes a pH neutral detergent wash followed by hot water extraction.

For additional information, see: Carpet Care and Use of Deicers.

BACK TO TOP

 

Q: Is it okay to use calcium chloride on stone surfaces?

A: Calcium chloride is not known to chemically attack stone under typical application conditions. However, if the stone is porous, melt water created during deicing may soak into pores or cracks, subjecting the stone to possible freeze-thaw damage. This type of damage is possible under certain conditions because melt water trapped in pores or cracks may re-freeze, creating a large amount of pressure beneath the surface of the stone. If the structure of the stone is not strong enough to withstand this pressure, the stone will flake or powder. This type of damage depends on the porosity and strength of the stone, not on the type of deicer used to melt snow and ice.

Because there are many different kinds and grades of stone, OxyChem cannot predict where damage may or may not occur. Therefore, OxyChem calcium chloride deicers are generally not recommended for applications on masonry (stone, brick and mortar joints).

 

Q: Can damage result from corrosion of rebar when chloride-based deicers are used on concrete structures, such as bridges and parking garages?

A: Chloride ions from deicing salts can permeate porous concrete. When chloride, oxygen and moisture come together on the surface of unprotected steel reinforcement (rebar) embedded in concrete, corrosion will result. Rust formation on rebar places pressure on the concrete that can result in cracking, spalling and delamination. The loss of bond between concrete and reinforcing steel and the loss of rebar cross-sectional area both have the potential to result in serious structural problems.

Companies and trade organizations with expertise in concrete construction technology are familiar with options available for corrosion protection in new or rehabilitated structures. With support from these experts, each end user should determine whether or not application of chloride-based deicers is appropriate for their given situation.

 

Q: Is it okay to use calcium chloride products for deicing wood surfaces?

A: The variety of wood treatments that could be used on exterior wood surfaces makes it difficult to predict the effect of calcium chloride deicers on those surfaces. Therefore, deicing wood surfaces with calcium chloride products is not recommended. Calcium chloride could potentially soak into untreated and some treated wood surfaces, resulting in damp spots that may be difficult to remove.

 

BACK TO TOP

Q: How should packages of solid calcium chloride be stored?

A: Solid calcium chloride is both hygroscopic and deliquescent. This means that the product can absorb moisture from the air, even to the point of converting to liquid brine. For this reason, protecting solid calcium chloride from excessive moisture exposure is the primary requirement to maintain product quality while in storage.

Packaged calcium chloride should be stored in a dry place. Avoid storing in areas where product leakage could cause damage. Some types of bags (i.e. valve closure bags) do not seal well if stored standing on end and should be stored lying flat. Opened packages should be tightly resealed after each use to prevent caking and liquid brine formation that may result from exposure to humid air.

Palletized product covered by an intact plastic shroud may be stored outdoors on a well-drained asphalt or concrete surface. If the shroud is torn, pierced or removed, the palletized product should be stored indoors or under a waterproof covering. Products packaged in drums or FIBCs (aka. Super Sacks or Big Bags) are typically not shrouded. Therefore, these packages should be stored indoors or under a waterproof covering.

Solid calcium chloride is temperature-stable under all ambient storage conditions.

For additional information, see Calcium Chloride: A Guide to Handling and Storage.

 

Q: What materials of construction are recommended for storing liquid calcium chloride solutions?

A: The preferred material of construction for large liquid storage tanks is carbon steel with an epoxy-based interior coating and a durable, high-quality coating on the exterior. Non-metallic materials, such as fiberglass or plastic, work well for smaller tanks storing product at ambient temperature; however, these materials are not as durable as carbon steel and they lose strength at high temperature.

For additional information refer to the publication, Calcium Chloride: A Guide to Handling and Storage.

 

Q: Can solid calcium chloride that has caked be made usable again?

A: When calcium chloride is stored in a manner that allows contact with humid air, the product is likely to become caked. If lightly caked, the product may be broken up into usable form by knocking the closed package against a hard surface, similar to breaking up a bag of ice from a convenience store. In other cases, the caked product may be too hard for this approach to be effective. Use of forceful hammering is not likely to be effective and is not recommended, as flying chips of product could be a hazard, particularly to eyes. Caked product that cannot be broken up into usable form may be disposed of according to guidance on the product label.

 

Q: Is calcium chloride safe for use near grassy areas and other vegetation?

A: Under typical applications conditions, calcium chloride will not damage grass or vegetation adjacent to a surface being deiced. As with fertilizer and any other deicer, it is possible for grass to be damaged if the chloride-based deicer is over-applied or large quantities are directly applied to the grass or vegetation. For additional information, see A Review of Deicers and their Effect on Vegetation.

MgCl2 and Vegetation — Don't be Misled

Deicer Blends and the Environment — Don't be Misled

*This information is not intended to be all-inclusive as to the manner and conditions of use, handling, storage, disposal and other factors that may involve other or additional legal, environmental, safety or performance considerations, and OxyChem assumes no liability whatsoever for the use of or reliance upon this information. While our technical personnel will be happy to respond to questions, safe handling and use of the product remains the responsibility of the customer. No suggestions for use are intended as, and nothing herein shall be construed as, a recommendation to infringe any existing patents or to violate any Federal, State, local or foreign laws.