Oil, grease, dirt, dust, salts and residues can interfere with primer or coating application. Cleaning and degreasing are selected around the contaminant, substrate and system requirements; corrosion, mill scale or failed coatings may require further preparation.
This short video introduces abrasive blast-cleaning, dry-ice cleaning, mechanical preparation and cleaning and degreasing, explaining the conditions each method may be used to address before coating application.
Watch the Surface-Preparation Guide
When Cleaning May Be Suitable
Preparing Suitable Surfaces Without Unnecessary Removal
Where steel or an existing compatible coating is stable and free from significant corrosion, targeted cleaning may be appropriate. The existing system, required finish and overcoating compatibility should still be confirmed before application.
Cleaning may be used before further preparation, before primer application or as a final cleanliness stage, depending on the accepted work sequence.
Common Surface Contaminants
Oil, Grease, Dust, Salts and Residues
Industrial and construction environments can leave oil, grease, dust, salts and other residues on structural steel. These contaminants may interfere with subsequent preparation, primer application or overcoating.
The cleaning method and acceptance criteria are agreed from the contaminant, selected product documentation and project specification. Further preparation remains necessary where cleaning does not produce the required surface condition.
Cleaning Methods
Selecting a Suitable Cleaning Technique
The technique is selected from the contaminant, substrate, existing coating, access and subsequent product requirements. A small trial may be appropriate where compatibility or effectiveness is uncertain.
Approved Solvent Cleaning
A compatible cleaner may be used for light oil, grease or residue on steel or an accepted existing coating. The wiping method should remove contamination rather than spread it, with SDS and COSHH controls followed.
Water and Pressure Cleaning
Water cleaning can remove loose dirt, dust and some soluble contamination where the substrate and site allow it. Pressure, water quality, runoff, drying and flash-rust risk must be considered before coating.
Detergent Cleaning
A compatible detergent may be used for stubborn oil, grease or atmospheric deposits. Product concentration, rinsing, waste handling and complete drying are managed in accordance with the accepted method.
Where Cleaning Is Not Sufficient
When Further Preparation Is Required
Cleaning alone is not suitable where coatings are loose, chalking, delaminated, unknown or incompatible, or where corrosion and mill scale remain. The affected areas require further investigation or an accepted mechanical or abrasive preparation method.
Clean Surfaces Support Subsequent Coating Work
Primers and intumescent coatings require a surface condition compatible with the selected system. Remaining contamination or weak coatings may interfere with adhesion and subsequent application.
Cleaning records provide a defined starting point for further preparation or coating. WFT control, drying conditions and final DFT inspection remain separate stages of the application process.
Product and Project Requirements
Cleanliness Requirements Must Be Confirmed
The accepted specification and selected primer or coating documentation define the required surface condition before application. Warranty, classification and formal approval depend on the complete system and project evidence — not cleaning alone.
Remove oil, grease, dirt, dust and specified salts
Allow the surface to dry within the selected product limits
Complete and record any required cleanliness checks
Myles Howson
Managing Director
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Other Surface Preparation Methods
Different substrate conditions require different preparation techniques. We assess corrosion levels, existing coatings and site constraints to specify the most appropriate method for compliance and long-term performance.
“After a decade in the protective coatings industry, I built FireCoatings to deliver fire protection without unnecessary noise — just clear documentation, a controlled application process, and professional site practice.”
Myles Howson
Managing Director
Client Feedback
"Thank you Myles and team for all your hard work on this one. It wasn't easy working around the schedule but you got it done without causing any further issues. It was a pleasure to work with you."
Chris
Project Manager, Millcroft Services
Client Feedback
"NuColour worked efficiently around our programme and delivered on time at late notice. The team were organised, flexible, and professional throughout the works."
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