Frequently Asked Questions
Below are frequently asked questions that OxyChem typically receives. Click on each question to reveal the answer.
General Calcium Chloride FAQs
Chemistry, Properties and Specifications
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.
Q: How can I dilute a liquid calcium chloride solution to hit a lower concentration target?
A: There are three different dilution options: (1) dilute with water; (2) dilute with lower concentration calcium chloride solution; or (3) dilute with both water and lower concentration calcium chloride solution. All three of these scenarios are covered in our easy-to-use Diluting Solutions Calculator tool.
Q: What is the pH of an OxyChem calcium chloride solution?
A: Accurate and consistent pH measurement in concentrated salt solutions is quite challenging. Results will vary significantly depending on the type of pH probe used and to what degree (if any) the solution is diluted prior to measurement. OxyChem calcium chloride products are somewhat alkaline due to the presence of a small amount of calcium hydroxide impurity. The pH reading for an undiluted sample of 35% solution should be approximately 9.
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 purchased 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 the eyes. Caked product that cannot be broken up into usable form may be disposed of according to the guidance on the product label.
Q: How can I obtain sales specifications for OxyChem calcium chloride products?
Storage and Handling
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: What is the shelf life of OxyChem's calcium chloride packaged product?
A: When properly stored to protect from moisture contact, the expected shelf life of all OxyChem calcium chloride packaged products is 36 (thirty-six) months.
Regulatory
Q: What are the HMIS and NFPA ratings for OxyChem calcium chloride products?
Q: Does OxyChem have a calcium chloride product approved by the EPA as an inert ingredient for pesticide formulations?
A: Yes. DOWFLAKE™ Xtra 83-87% Calcium Chloride Flake is approved by the EPA as an inert ingredient for pesticide formulations (Reference: 40CFR 180). Approved uses include:
• Stabilizer in pesticide formulations applied to growing crops or to raw agricultural commodities after harvest
• Stabilizer in pesticide formulations applied to animals
• Non-food use pesticide product formulations
• Antimicrobial pesticide formulations applied to dairy processing equipment and food processing equipment and utensils
• Pesticide formulations for food processing equipment and utensils when the end-use concentration of the trade name product does not exceed 19.5 ppm
Q: Do OxyChem calcium chloride products meet the REACH (Registration, Evaluation and Authorization of Chemicals) requirements set forth by the European Union?
A: OxyChem is committed to comply with REACH, the EU regulatory system for chemicals management to protect the environment and preserve the future of the chemicals industry in Europe. OxyChem successfully registered calcium chloride under REACH. OxyChem’s European Safety Data Sheets will reflect the registration numbers and exposure data required by REACH.
Please Contact Us for additional information.
Sidewalk Ice Melting
Application Guidelines
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.
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.
Usage on Specific Surfaces or Areas
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: 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.
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: 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: Are calcium chloride-based deicers “pet-friendly”?
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
Considerations
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.
Road Improvement
Application Guidelines
Q: What are the application guidelines for using calcium chloride to control dust on gravel surfaces?
A: Various forms of calcium chloride have been used to control dust on gravel roadways for over 100 years, improving safety and comfort for travelers while reducing maintenance costs for road managers.
The most desirable product for any given situation is a matter of personal choice. Solid calcium chloride products may be spread directly, or dissolved in water and spread as a liquid. In the U.S., the most common liquid concentration used for dust control is 38%. In Canada, the most common concentration is 35%. Liquid concentrations higher than 38% may be used; however, higher concentrations are more likely to crystallize as the solution cools. Learn More.
Considerations
Q: Is calcium chloride used for dust control corrosive to vehicles?
A: Noticeable vehicle corrosion is not likely to be associated with dust control applications of calcium chloride. First, the application rate is relatively low, so there is not much calcium chloride available to come into contact with passing vehicles. Second, the calcium chloride tends to remain in the road bed. If it didn't, it wouldn't control dust very well because it would disappear from the road after a short while. If it is suspected that a vehicle has come into contact with calcium chloride, a basic wash of the vehicle will remove this highly soluble salt.
Q: Is calcium chloride safe for use around grassy areas and other vegetation?
A: Under typical application conditions, calcium chloride will not damage grass or vegetation adjacent to a road surface where dust control is applied. As with fertilizer and any other road dust control chemical, it is possible for grass to be damaged if the calcium chloride is over-applied or large quantities are directly applied to grass or vegetation.
Q: Is liquid magnesium chloride lower in chloride and safer for the environment than calcium chloride?
A: No. The chloride content of liquid material is determined by the concentration of the solution, and the molecular weight of the salt. For example, a 30% solution of magnesium chloride would have about the same chloride content as a 35% calcium chloride solution. A 2008 study by researchers at Colorado State University1 and a report by the U.S. Department of Agriculture Forest Service2 concluded that the impact of magnesium chloride is no less than other chlorides. Equally important in determining environmental impact is the application rate of the product. A more concentrated product can achieve the same results at lower application rates. While magnesium chloride is commercially available in 30% solutions, LIQUIDOW™ is typically applied at concentrations of 35% or 38% for dust control and road base stabilization applications, which means less calcium chloride may be required to achieve the same result. This is supported by best practices published by Environment Canada recommending an application rate of 1.4 to 2.3 l/m2 of magnesium chloride to achieve the same dust suppression capability as calcium chloride applied at a rate of 0.9 to 1.6 l/m2.3 The USDA Forest Service found that a magnesium chloride application rate of 0.30 to 0.50 gal/yd2 was necessary to achieve the same dust suppression performance as 0.20 to 0.35 gal/yd2 of calcium chloride.2
1Condition of Soils and Vegetation Along Roads Treated with Magnesium Chloride for Dust Suppression, B.A. Goodrich, R.D Koski, and W.R. Jacobi, March, 2008.
2Dust Palliative Selection and Application Guide, USDA Forest Service, P. Bolander and A. Yamada, November, 1999.
3Best Practices for the Use and Storage of Chloride-based Dust Suppressants, Environment Canada, February, 2007.
Highway Ice Melting
Considerations
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.
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.
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 calcium chloride safe for use near grassy areas and other vegetation?
A: Under typical application 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. Roadside damage to conifers caused by contact with chloride-containing mist from high-speed tire action is a potential issue with highway applications of any chloride-based deicer.
For additional information, see: A Review of Deicers and their Effect on Vegetation
Other Applications
Food and Beverage
Q: How can I get a copy of the kosher certificate for food-grade calcium chloride products?
A: A copy of the current kosher certificate for all OxyChem food grade calcium chloride products can be obtained here.
Q: Are allergen, GMO and other certification statements available for food grade calcium chloride products?
Q: Are OxyChem’s food grade calcium chloride product facilities audited?
A: Yes. Located in Ludington, Michigan, the facilities associated with the manufacture and packaging of OxyChem's food grade calcium chloride products undergo an annual audit of Good Manufacturing Practices and Food Safety Systems conducted by a reputable, independent auditor.
Please Contact Us for additional information.
Q: Is nutritional information available for food grade calcium chloride products?
Q: Are OxyChem calcium chloride products NSF-certified for treatment of drinking water?
A: No. OxyChem calcium chloride products are not certified per NSF/ANSI 60, Drinking Water Treatment Chemicals; or NSF/ANSI 61, Drinking Water System Components.
Q: Does OxyChem have a calcium chloride product recommended for use in drinking water applications?
A: No. OxyChem recommends against using our calcium chloride in drinking water applications due to the presence of impurity bromide. Bromide can react with oxidizers used for water sterilization to form bromate. In many countries, drinking water standards restrict bromate to very low levels. These standards may not be met if drinking water is treated with our calcium chloride and sterilized with oxidizing chemicals, such as ozone.
Concrete
Q: What are the recommendations for addition of calcium chloride to concrete when used as an accelerating admixture?
A: The amount of calcium chloride used should not exceed 2% and application rates should vary with temperature. Addition rate specific recommendations may be found in the document referenced below. Calcium chloride should preferably be added in solution form to aggregates in the mixer drum or as a portion of the mixing water. Add calcium chloride at the ready mix plant if the concrete will be discharged within one hour of the start of mixing. Otherwise, add it at the job site, mixing for at least three minutes or 30 revolutions of the mixer, whichever is longer. If dry calcium chloride is used, it should be free of lumps and added to aggregates in the mixer drum before mixing, or to the mixed concrete just before discharge. Please refer to the publication Calcium Chloride in Portland Cement Concrete for more complete information about the use of calcium chloride as an accelerating admixture.
Q: Are there applications where calcium chloride should not be used as a concrete accelerating admixture due to potential corrosion issues with reinforcing steel?
A: Consult the most recent reports from the following American Concrete Institute (ACI) committees for information about the amounts of calcium chloride that are allowed in concrete under various exposure conditions, and conditions in which calcium chloride should not be used. Relevant reports include:
ACI 201 Durability of Concrete
ACI 212 Admixtures for Concrete
ACI 222 Corrosion of Metals in Concrete
ACI 306 Cold Weather Concreting
ACI 318 Standard Building Code for Reinforced Concrete
Pool and Spa
Q: Can OxyChem calcium chloride products be used to adjust the calcium hardness in pool and spa water?
A: Yes. However, because solid calcium chloride currently manufactured by OxyChem contains approximately 6000 - 8500 ppm bromide, users should be aware of potential interactions with other pool chemicals. While the presence of bromide in pool and spa water is not uncommon – it is often present in disinfectants – it can react with other chemicals to form unwanted disinfection by-products. Please refer to the publication Pool and Spa Water Treatment Applications for information about the use of calcium chloride to adjust the calcium hardness in pool and spa water.
Freeze-Proofing
Q: What are the recommendations for use of calcium chloride to freeze-proof water-filled containers?
A: Technical grades of solid and liquid calcium chloride may be used to freeze-proof water-filled containers, such as traffic barriers. The target concentration depends primarily on the level of freeze protection desired. See below for the freeze points of typical concentrations. 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.
Wt% |
Sp. Gr. |
lbs/gal |
Freeze Pt. |
16% |
1.149 |
9.55 |
+8°F |
20%; |
1.189 |
9.88 |
-4°F |
24% |
1.228 |
10.20 |
-20°F |
28% |
1.275 |
10.60 |
-46°F |
32% |
1.322 |
10.99 |
17°F |
*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.