PAINTING FOR STRUCTURAL STEEL
PART 1 GENERAL
1.1SECTION INCLUDES
A.Prepare and paint all surfaces except where indicated otherwise.
1.2RELATED SECTIONS Not Used
1.3REFERENCES
A.ASTM D 4285: Indicating Oil or Water in Compressed Air
B.ASTM D 4417: Field Measurement of Surface Profile of Blast Cleaned
Steel
C.ASTM E 11: Wire Cloth and Sieves for Testing Purposes
D.American Institute of Steel Construction (AISC)
E.Federal Standards
F.Mine Safety and Health Administration (MSHA) Standards
G.National Institute for Occupational Safety and Health (NIOSH) Standards
H.Northeast Protective Coating Committee (NEPCOAT)
I.The Society for Protective Coatings (SSPC)
1.4DEFINITIONS Not Used
1.5SUBMITTALS
A.Materials
1.Source and gradation of the blast abrasive.
2.Type and source of solvent if required.
3.Manufacturer’s information regarding the specified coating
materials, including:
a.Required wet and dry film thickness
b.Project safety data
Painting For Structural Steel
c.Thinning recommendations
d.Temperature requirements
e.Profile recommendations
f.Mixing and application procedures
g.Required equipment
h.Method of application
4.Test samples. Refer to this Section, article 1.6.
B.Qualifications, methods, and documentation.
1.Certifications before the preconstruction meeting. Refer to this
Section, article 1.7.
2.Detailed plan of protection methods that includes Environmental
Protection for approval.
3.Quality Control Plan that contains at a minimum procedures and
verification of the following:
a.Compression air check
b.Dry film thickness – Refer to SSPC-PA 2
c.Air temperature
d.Humidity and dew point
e.Surface temperature
f.Abrasive cleanliness check – Refer to SSPC-AB 2
g.Degree of cleanliness achieved
h.Surface profile – Refer to ASTM D 4417 method C
i.Batch number and amount of thinner used
j.Batch number of paint used
k.Mixing procedures
l.Paint repair procedures for scratches, gouges, holidays, mud
cracking, runs, and sags
4.Daily reports upon request.
a.Submit no later than 24 hours following the completion of
work.
1.6TEST SAMPLES
A.Department tests paint samples from each batch or lot before use.
1.Submit samples for verification.
2.Paints must match the spectrum samples on file with the
Department
Painting For Structural Steel
1.7PAINTER AND SANDBLASTER QUALIFICATIONS
A.Contractors and subcontractors performing surface preparation or
coatings applications in the field.
1.Must have SSPC-QP 1 certification before the preconstruction
meeting.
2.Remain certified for the duration of the project.
B.Contractors, subcontractors, and fabricators performing shop surface
preparation or coatings applications.
1.AISC-420-10/SSPC-QP 3 enclosed shop certification before the
preconstruction meeting.
2.Remain certified for the duration of the project.
a.Do not perform work if certification has expired.
3.Notify the Department of any change in certification status.
PART 2 PRODUCTS
2.1MATERIALS
A.Select a complete three-part coating system consisting of a zinc primer,
epoxy or urethane intermediate coat, and aliphatic urethane top coat from the NEPCOAT Qualified Products List. Refer to http://www.udot.utah.gov/go/standardsreferences.
B.Use paint color No. 26293 for the first field coat and No. 26306 for the top
coat following Federal Standard 595.
PART 3 EXECUTION
3.1GENERAL
A.Use manufacturer’s information regarding the specified coating materials
including required wet and dry film thickness, project safety data, thinning recommendations, temperature requirements, profile recommendations, mixing and application procedures, and required equipment.
3.2INSPECTION
A.Engineer examines surfaces before surface preparation and before
application of each succeeding coating. Correct any condition that is determined by the Engineer to negatively affect a proper coating application.
Painting For Structural Steel
B.Provide safe access to permit inspection of the steel before and after
painting. Use rubber rollers or other approved protective devices for scaffold fastenings. Do not mar or damage freshly coated surfaces.
3.3PREPARE SURFACES
A.Painted steel – Clean surfaces with clean petroleum solvents and then
blast clean to a near-white condition following SSPC-SP 10. Use clean oil-free air.
1.Grind off all fins, tears, slivers, and burred or sharp edges present
on any steel member or those that result from the blasting operation.
a.Reblast where needed.
b.Remove all mill scale.
c.Do not scar metal.
d.Grind the edges of all flame cut steel until the hardened
edge accepts the blast profile. Refer to ASTM D 4417 method A.
e.Produce a 0.5 - 3 mils uniform profile not to exceed
manufacturer’s recommendation.
2.Remove all abrasive and paint residue using either a commercial
vacuum cleaner or by double blowing.
a.Equip commercial vacuum cleaner with a brush-type
cleaning tool.
b.Double blowing – Vacuum the top surfaces of all structural
steel, including items such as top and bottom flanges, longitudinal stiffeners, splice plates, and hangers after the double-blowing operations are completed.
3.Keep the steel dust free and prime within 8 hours after cleaning.
Reblast to a near-white condition if any rust is visible before priming.
4.Protect freshly coated surfaces from subsequent blast-cleaning
operations.
a.Repair surface if damaged.
b.Mask all areas requiring field welding before shop painting.
5.Have the surfaces inspected and approved by Engineer or
Construction and Materials Division representative of Department before applying shop coat.
6.Apply the shop coat at the fabrication site. Apply coatings at the
fabrication site in an enclosure with a controlled environment to match optimum conditions for application and curing as stated in the manufacturer’s product data sheet.
7.Apply mist coat to the top flange.
Painting For Structural Steel
B.Field Painting
1.Repair all damage to shop coat that occurs during shipping,
handling, and erection.
2.Power wash steel without the field coat to remove contaminants or
other foreign matter from the primed surface.
3.Blast clean bolt heads, fasteners, and any rusted areas to a near-
white finish. Thoroughly clean the coating surrounding the blasted area and re-prime the same day using organic zinc from the same paint manufacturer and the same dry film thickness specified for the shop coat. Follow SSPC-SP 10.
4.Remove all concrete drippings, abrasive, and paint residue.
Vacuum items such as the top and bottom flanges, splice plates, longitudinal stiffeners, and hangers after completing double-blowing operations.
5.Allow the touch-up coat to dry according to manufacturer’s
recommendation as listed on the product data sheet.
3.4PREPARE PAINT MATERIALS
A.Mix and thin paint materials according to manufacturer’s product data
sheets for both shop and field painting.
B.Mix the paint to a lump-free consistency with a high shear mixer such as a
Jiffy mixer according to the manufacturer’s directions.
1.Do not use paddle mixers or paint shakers.
2.Keep paint in the original containers.
3.Mix until all the metallic powder or pigment is suspended and until
all paint solids that may have settled to the bottom of the container are thoroughly dispersed.
C.Strain the paint through a screen having openings no larger than those
specified for a No. 50 sieve according to the material standard. Refer to ASTM E 11.
D.Strain and continuously agitate the mixed material up to and during
application.
3.5APPLY PAINT
A.Apply field coats at the construction site after steel erection work is
completed.
1.Do not apply field coats until Engineer verifies the surface.
2.Dry film thickness of the first field coat must be greater than 4 mils.
3.Keep the dry-film thickness of the top coat greater than 2 mils.
Painting For Structural Steel
B.Use wet and dry film thickness gauges for testing the coating thickness
during and after application.
C.Apply each coat at required consistency and thickness according to the
manufacturer’s recommendations including field coating. Use pressures recommended by the manufacturer of the coating system when using spray nozzles.
D.Produce a uniform, even coating that bonds to the underlying surface.
Refer to SSPC-PA 1.
E.Weather
1.Follow the manufacturer’s recommendations if weather conditions
require paint thinning.
2.Temperature of the air and the steel must be above 40 degrees F,
but not so hot as to cause the paint to blister.
3.Relative humidity must be less than 85 percent or the combination
of temperature and humidity conditions must inhibit surface condensation.
4.Test humidity by applying a thin film of water to a small area.
Surface may be painted if the film evaporates within 15 minutes.
5.The steel temperature must be a minimum of 5 degrees F above
the dew point.
F.Use necessary equipment for the proper application of the specified
coating. Observe safety practices found in SSPC-PA Guide 10, “Guide to Safety and Health Requirements.”
G.Blast clean any shop coat that shows any indication of “mud-cracking” or
adds more than 7 mils to a soundly bonded coating or bare steel. Refer to SSPC-SP 10.
H.Thoroughly clean areas that have deficient primer thickness to remove all
dirt.
I.Apply an intermediate and top coat to any surface at the fabrication site
that will be inaccessible for painting after field erection.
J.Do not load structural steel for shipment until shop paint is dry to the
touch.
K.Protect all paint systems. Place softeners between plates of cross frames
and diaphragms.
Painting For Structural Steel
3.6PROTECTION
A.Stop work if protection is unsatisfactory.
B.Protect pedestrian and vehicular traffic.
C.Protect all portions of the structures that are not to be painted from
splatter, splashes, and overspray including superstructure, substructure, slope, and highway appurtenances. Protect areas during painting and blast cleaning operations where other damage can occur.
D.Use barriers during any blast-cleaning operations to protect pedestrians
and vehicles and to prevent spreading or falling of abrasive materials and debris on the traveled portions of the pavement. Remove any abrasive materials and debris on pavement, shoulders, or slope paving before reopening work areas to traffic.
E.Provide employees performing the blast-cleaning operations air-supplied
blasting hoods approved by the Mine Safety and Health Administration and the National Institute for Occupational Safety and Health.
F.Minimum requirements for the air supply system:
1.Airline filter, pressure-reducing valve with gauge and pressure
release valve.
2.Do not allow the air supply to be contaminated with harmful
materials or elements. Refer to ASTM D 4285.
3.7QUALITY ASSURANCE
A.Minimum Coating Thickness – Apply two or more coats if the required film
thickness cannot be obtained by one coat without producing runs, bubbles, or sags.
B.Refer to SSPC PA 2.
END OF SECTION
Painting For Structural Steel
Utah revises spec sections through supplementals and new editions. We check this one every week and email you the day it changes. Free, no account.
Source: Utah Standard Specifications for Road and Bridge Construction, 2026 Edition. Pages 1189–1195 of 1,331.
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