Bond to the steel: investigate sprayed fireproofing adhesion concerns
Fireproofing has come away from several lower beam flanges at a food-processing plant. The steel beneath looks shiny, but nobody has confirmed what is on it. Before the crew patches the same area again, you need a record that supports an investigation rather than a confident guess.
Record the affected locations and compare substrate, coating and application evidence with the actual product requirements before deciding a correction. Surface contaminants can impair adhesion, as the opened Canadian replacement-product instructions explain. A loose sheet or crumbling edge does not by itself prove that primer, oil, mixing or one operator caused the problem.
Investigate before repeating the patch
- Record the condition without disturbing it. Identify member marks, level, grids, observed damage and when it was reported. Use permitted photographs and the project's access arrangements. Keep people clear of the affected condition as directed by responsible site personnel; do not pull more material away to create an informal diagnosis.
- Compare the affected locations. Check the delivery and coating records, approved substrate decisions and any preparation evidence. Identify similarities and differences across affected and apparently unaffected members. Record missing information as missing rather than treating a shiny surface as proof of a release oil or an unfamiliar coating as the proven cause.
- Bring application evidence into the review. Link the locations with product lots, batch records, equipment changes and conditions recorded during work. Have the qualified installer compare those records with the selected instructions. Preserve the evidence before altering the process; another spray pass can otherwise obscure what happened in the first application.
- Agree the technical investigation. Ask the manufacturer, consultant and agency for the required checks and their scope. ASTM E736/E736M's public scope concerns tensile cohesion/adhesion testing; it does not provide a visual diagnosis or a universal passing value. Do not substitute hand-pulling, one sample or an informal trial for the agreed investigation.
- Record the directed correction. Identify preparation, coating decisions, application changes or repairs required by the responsible review. State the affected scope and the evidence needed afterwards. A bonding agent is an option only where the actual system and decision permit it, not a routine answer to every concern.
- Check the next area deliberately. Brief the crew on the resolved method and keep changed deliveries or conditions visible. Review the required evidence before closing the original item. Use recurring locations to improve the investigation record, without promising that one correction eliminates every future adhesion problem.
Common mistakes
- Naming a cause before obtaining the coating or preparation evidence.
- Replacing the formal investigation with hand-pulling.
- Patching the appearance while leaving the original decision unresolved.
Action list
Keep an adhesion investigation file
- Condition and member locations.
- Coating and preparation evidence.
- Linked application and conditions records.
- Directed checks and governing criteria.
- Correction scope and required follow-up.
- Documented closure or remaining question.
Check your understanding
The exposed steel looks oily. Can you instruct a bonding agent as the final remedy?
Show the answer
Confirm the surface condition and obtain the system-specific correction first. Appearance does not establish the cause, and a bonding agent cannot replace the required compatibility and acceptance decisions.
