During my time at MDOT, we wanted a simple guide to Anti-Icing with a Chloride based Agricultural By-Product. I put together this simple to follow guideline as a starting point for our drivers to understand how these products work. Applications rates can be varied depending on your experience and knowledge grows with the deicer/anti-icers you are using. I have also included with this a guide for field testing liquids as you take delivery. I hope you find this helpful.
Anti Icing Guidelines
Guidelines for use with Calcium or Mag Chloride & Agricultural By-Product.
Anti-icing operations should not begin until after the first snow event that requires snow removal operations to be performed. This will provide a “scrubbing” of the road surface allowing oils and other contaminants to be cleaned from the roadway.
Anti-Icing may be done at any time prior to a predicted winter storm event. The products tested and used have remained effective for up to one week. It is not recommended that this or any Mag Chloride (MgCl2) or Calcium Chloride (CaCl2) / Agricultural By-Product be used in a scheduled anti-icing mode. For example, salt brine used for anti-icing bridges and trouble areas have been applied twice weekly in some States. When this is done with MgCl2 or CaCl2, it can accumulate and if no frost or snow events occur, cause an over application situation.
Application Rate – 20 – 30 gallons per lane mile. you may want to start @ 25 g.p.m. to see how it works for you. Do Not go above 30 g.p.m. More in this case is not better.
Bridges for frost application rate 10 -15 g.p.m.
Ramps or stops at intersections. 10 to 15 g.p.m. more may make it slippery. When Anti-Icing off ramps and on ramps, shut off application at the halfway point of ramp. This will not allow equipment to “drizzle” @ stops or double applications on freeways which cause an over application.
DO NOT overlap routes when anti icing. This is done during snow removal operations and can increase your application rate and may cause slippery conditions when anti-icing. Material can track for up to a mile, depending on conditions and pavement type.
DO NOT apply when road surface temps are at 35 degrees and rising. If during an application the surface temps are rising, the operation should stop and then resume when temperatures are below the 35 degree mark. Applications with surface temperatures over 35 degrees may cause slippery conditions.
Take the wind forecast into account when deciding to apply. If it’s supposed to be windy with drifting, don’t apply. Just like salt it will cause the road become wet.
Application: Spray bars should use ¼” streamer nozzles with a 10” spacing. It is recommended that drop tubes be used for application speeds over 20 mph.
1. Document and maintain records on all deliveries, including those that are rejected.
2. Check to assure that the product is being delivered according to the terms of the contract. This includes but is not limited to the following:
a. Date of the order.
b. Date and time of delivery.
c. Verification of advance delivery notification.
d. Delivered within allowable times.
e. Name of delivery company and license plate numbers.
f. Is any price adjustment assessments required?
g. Is the product being delivered what you ordered?
h. Document all procedures prior to unloading of product.
i. Verify that all papers required of a delivery are present, complete, and legible.
3. Legible and current MSDS sheet. Optional if
4. Certified weight slip.
5. Accurate, complete, and legible bill of lading and/or invoice with the information as required.
SAMPLING AND TESTING
1. One sample of all products will be taken from each load of product being delivered at the time of delivery. Clearly label samples for identification. If testing is desired, send the sample directly to a qualified contract Laboratory. Samples sent to the Laboratory will be tested for conformance to the specifications to insure product quality. Be sure the chain of custody form is placed in the box and contains at least the following information: Manufacturer or bidders name, name of product, lot number of product, shipping date, date received, name of delivery point, quantity of material delivered, and name and phone number of person who received the load and took the samples. Test results from the Laboratory will be final and in the best interest of MDOT. The supplier will be notified of test results only if a problem is detected.
2. Check and record the specific gravity and pH of the samples if desired.
The product must be completely formulated and mixed at the original manufacturing plant location. Post adding of corrosion inhibitors or any other ingredients (other than anti‑foaming agents) and splash mixing is unacceptable after the product has left the original manufacturing plant.
1. Visually inspect the load to determine if there are any obvious reasons why the load should be rejected.
2. Note the amount of product currently in storage prior to unloading.
3. Visually inspect the delivered product again while unloading. If problems are noted that are a cause for rejection of the load, halt the unloading process. Take photos if applicable and record any pertinent information. Conduct the following procedures if the material is to be rejected:
a. If material fails initial inspection or testing reload the product and reject the load.
b. If reloading can’t be done, (mixed with previous material) note the amount of product (liquid only) pumped into the tank and total product now present in the tank.
c. Circulate the tank and then pull two one‑gallon (4 Liter) samples of the contaminated chemical material now in the tank
d. Check and record the specific gravity of the samples.
e. Take appropriate action as needed to assure the integrity of product on hand if possible. Will all products on hand have to be removed?
f. If testing is desired, send samples directly to a qualified contract Laboratory.
g. Immediately advise the supervisor of any ordering, delivery, storage, or product quality issues.