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The Bridge Technical Community of Interest is a group of professionals (both AMPP members and nonmembers) that will include, owners, manufacturers, consultants, contractors and others who have come together to share and discuss issues affecting the bridge industry and new and emerging technology. Through the shared knowledge of this diverse group, both geographically and from varying viewpoints, information can be discussed about current issues for both the design phase and construction phase. This can include the selection of containment to surface preparation and materials, abrasives, coatings, solvents, etc. during the design phase and issues during the actual construction phase with the contractor’s submittals, means and methods. The sharing of knowledge on how to deal with structural issues that could be detrimental to the life of the newly applied system can be discussed along with new and emerging technologies and how they can be incorporated into bridge coatings to streamline those processes and possibly lower the overall costs.
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Abrasive Blast Cleaning Inspection & Surface Profile Measurement Method

  • 1.  Abrasive Blast Cleaning Inspection & Surface Profile Measurement Method

    Posted 05-16-2023 10:12 AM

    Abrasive blast cleaning inspection requires the inspector to understand the customer specifications and the approved equipment required for the inspection. For example, if the customer specs call for ASTM D4417 Method B or Method C for profile measurements and SSPC-VIS 1 for verifying cleanliness to SSPC-SP 5.

    Also, acceptable variations in appearance that do not affect cleanliness as defined in the SSPC-SP 5 standard, such as original surface condition, fabrication mark, etc., need to be reviewed and agreed upon at the pre-job conference. The QA inspector must ensure that blast equipment such as Elcometer 224 digital surface profile gage is calibrated on glass and verified to a known surface profile shim approx. 5 miles. See the images below.


    Flashlight angles are also critical during the inspection due to the incident/refractive rays of light. It would help if you didn't use a flashlight at 90 degrees angle to the steel substrate. Manufacturer calibration and verification by the project inspector is very critical for the owner on the way go before any spray application final decision. If profile measurements are low, this could lead to mechanic adhesion failure & if peaks are too high, it could create rash rust, esp. if it's a single-coat system.

    ~Shared by RCSI AMPP Senior Certified Coatings Inspector.

    Elcometer 224 Digital Surface Profile Gauge

    Bridge Blast Cleaning Assessment


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    Olumide Aluko
    Coating Engineer
    Arcosa USA
    McKinney TX
    +12818577607
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