Section 8: Testing
Anchor: #i1001189Material Specification DMS-6400
TxDOT developed Departmental Material Specification DMS-6400, modeled after the Pacific Northwest States specification, to ensure the quality of anti-icers and de-icers. DMS-6400, De-icer/Anti-icer, describes the requirements, testing methodology and a Quality Monitoring Program (QMP) for magnesium chloride (MgCl) and sodium chloride (NaCl).
Calcium magnesium acetate (CMA) and potassium acetate (KAc) are used in Texas in smaller quantities. These and other materials must be tested prior to use, in accordance with TxDOT standards. Click here for more information.
For producers of MgCl and NaCl products to be considered for inclusion in the Department’s Quality Monitoring Program (QMP), a producer must contact the Materials and Pavement Section of the Construction Division (CSTM) and submit a sample for evaluation. The sample must include test results from an independent laboratory indicating compliance with the requirements set forth in DMS-6400. After evaluation and specification compliance, the producer and material will be included on the Material Producer List (MPL).
A district may purchase any anti-icer/de-icer listed on the MPL with only verification sampling advised. Those anti-icers/de-icers not on the list will require full independent lab testing and CSTM verification before application.
The following properties are verified at the CSTM laboratory:
- corrosion
- sulfate
- percent total settleable solids and percent solids
- specific gravity
- pH.
These tests were developed to ensure an environmentally sound material. Results from chemical properties are to be submitted every time material is ordered and delivered.
All material supplied must include the following documentation:
- current, clearly legible Material Safety Data Sheet (MSDS)
- clear documentation of its percentage of concentration of MgCl
- an application rate table that clearly states the manufacturer/vendor/supplier recommended rate for the various conditions of use at the place of delivery
- shelf life of material
- a Friction Analysis Report on all products. Any certified
lab that is set up to run the test as a function of humidity and
for the type of roadway [asphalt or concrete] specified may perform the
test. Required information includes:
- hard data
- graphical analysis
- a write-up about the product typically with comparison information.
- information on how low temperatures will affect storage of liquid material
- clear documentation on proper storage
- certification that any MgCl supplied meets test methods SHRP-H-205.2 for effectiveness (Strategic Highway Research Program Handbook of De-icer Test Methods).
Upon delivery, it is very important that a TxDOT representative visually inspect the load for any obvious reasons for rejection. For example, no precipitates in liquid products are allowed in excess of the specification limits. Material portraying these or other uncharacteristic traits when delivered may be immediately rejected at the option of the engineer or representative at the delivery location.
In addition to verifying that a delivered liquid chemical meets the current specification, two additional tests, viscosity and specific gravity, may be performed at the district level to determine whether the right liquid chemical is delivered.
The viscosity test provides useful information that clearly indicates the chemical concentration of the liquid chemical. Specific Gravity is a quick and simple verification acceptance test.
The two tests provide a simple and inexpensive mechanism for a district to ensure that the right chemical is being accepted at delivery. For more information on quality control testing, please contact the Materials and Pavement Section of the Construction Division (CSTM).