This IM provides the instructions on how to become approved as an epoxy coater.  Approved sources of epoxy coated reinforcement can be found in the Materials Approved Products Listing Enterprise (MAPLE).



Prior to furnishing reinforcing steel or wire mesh reinforcement on a certification basis, the following documents shall be submitted:

1.     A request shall be submitted to Central Construction and Materials Office in Ames, Iowa detailing the location of the manufacturing plant and any distribution center(s).


2.     Epoxy Coating Plants shall be certified by the Concrete Reinforcing Steel Institute (CRSI) for Fusion-Bonded Epoxy Coating Application.


3.     Sources of steel that would be handled by the company and supplied to Iowa DOT projects.


4.     Quality control procedures, meeting the minimum requirements outlined below, the company has established to ensure material identity (as to heat numbers and inventory control) from the time the material arrives from the mill or a source, through the coating and fabricating process, shipment and record retention to satisfy IM 107 Buy America.


5.     Coating quality procedures to ensure the coated steel complies with Iowa DOT Specification.  This shall include the following:


a.     Names of quality control personnel.

b.     Quality control testing conducted during the bar cleaning operation.

c.      Quality control testing conducted on the epoxy coating after coating.


6.     Sample three epoxy coated bars of every size that the coater plans to coat.  The bars shall be approximately 6 ft. in length.  Samples are to be secured by the District Materials Engineer for the source approval.


7.     An example of certification documents that the company will furnish the Iowa DOT projects meeting the requirements in IM 451.03B.


8.     Copies of the last three CRSI inspection reports must be submitted for review and evaluation.


Upon satisfactory review of this application, satisfactory test results and satisfactory inspection of the facilities for compliance with quality control procedures, the company will be placed on the approved list.


Once approved, the coater shall forward a copy of their latest CRSI inspection report on a yearly basis for continual approval.



The coating plant shall maintain an updated Quality Control Manual.  The coating plant shall also have a trained designated Quality Control Inspector, as well as trained personnel to perform QC functions for every production shift.  Inspection and testing shall be performed in a timely manner during each production shift.

The Plant is responsible to maintain a record of Quality Control monitoring and testing, and document Quality Control meetings and training with personnel.



The abrasive blasting media shall be inspected for contamination every production shift and a sieve analysis shall be performed at a minimum of twice per week.





·        A single recorded epoxy coating thickness measurement shall be the average of three individual gage readings obtained between four consecutive deformations. A minimum of five recorded measurements shall be taken approximately evenly spaced along each side of the test bar (a minimum of 10 measurements per bar).


·        Note: All individual gage readings shall be reported along with the averages.


·        Note: The upper thickness limit shall not apply to repaired areas of damaged coating.


·        Test for coating thickness shall be made on a minimum of two bars every two production hours or whenever bar size changes.



Coating continuity shall be monitored by:

·        An In-Line Holiday detector


·        A Hand-held Holiday detector (wet sponge type)


Hand-held Holiday detection checks shall be performed at a minimum rate of once per shift. The accuracy of the In-Line System shall be compared to the accuracy of the Hand-held detector at all times. There should be fairly close correlation between the Hand-held and In-Line Holiday counts. Only 1 Holiday per 1.0 linear foot shall be allowed over the length of the coated bar.



A bend test shall be performed to evaluate the flexibility of the coating. Coated bars shall be tested at a uniform rate, a minimum of one bar of each size every four production hours around a mandrel of a specified size within a maximum specified time period. (See Table 1, ASTM A775/AA775M.)  No cracking or disbonding of the coating shall be visible on the outside radius of the bent bar. Evidence of cracking or disbonding of the coating shall be considered a cause for rejection. The test bars shall be between 68˚F and 86˚F when tested.



Epoxy Powder shall be stored in a suitable temperature and humidity controlled environment within the epoxy powder manufacturer’s specified limit.  The powder storage area shall be equipped with a recording gauge and an alarm system.


The powder shall be kept dry at all time. The Epoxy powder shall be used within the manufacturer’s recommended shelf life. Epoxy powder that has exceeded the manufacturer’s “Use-By” date shall not be used.



All systems for handling epoxy coated steel bars shall be padded.  All bundling bands shall be suitable banding to prevent damage to coating.  All bundles of epoxy coated steel bars shall be carefully lifted to prevent bar-to-bar abrasion, sagging of bars, and/or damage to coating. 


If coated bars have been stored outside at the coater for a period of six months or longer from the date of coating, the coater shall inspect, sample, and retest the bars prior to shipment to a warehouse or project site.  If coated bars have been stored indoors at the coater for a period of one year or longer from the date of coating, the coater shall inspect, sample and retest the bars prior to shipment to a warehouse or project site.  Bars shall be retested for coating thickness and flexibility (bend test).  A copy of the test results shall be attached to original coating report.




·        Sheared ends and / or saw cut ends of coated reinforcing bars shall have adequate coating, have no signs of surface rust or damage, and shall be coated and or repaired with approved patch / repair material listed in IM 451.03B Appendix B.


·        Repaired / Patched areas shall be allowed to cure (dry to touch) before concrete placement over the coated bars.


·        Surface preparation, repair, and patching application procedures shall be in accordance with the powder manufacturer’s recommendations.



Rejected bars shall be marked with contrasting color paint or other suitable identification and stored separately.



The producer of the epoxy coated bar reinforcements shall furnish on each shipment day a certified bill of materials or invoice, which identifies the county, project number, contractor’s name and the size of the epoxy coated bars. The certification of compliance shall be signed by a designated or responsible company representative and shall be stated as follows:


The materials itemized in this shipment are certified to be in compliance with the applicable ASTM Standards and the Iowa Department of Transportation Standard Specifications, IMs and meet the Buy America requirements as described in IM 107 for all steel, iron products and coatings.




Authorized Signature & Date