Intumescent Paint Method Statement for Structural Steel

Q: How is the required intumescent DFT determined?

By manufacturer’s design based on each member’s section factor (Hp/A), fire rating duration, and exposure. Use the approved coating schedule and verify per project specifications.

Q: What environmental limits apply during application?

Typically steel temperature ≥3°C above dew point, RH ≤85%, and substrate/application temperatures within the product’s PDS. Always verify project/manufacturer limits.

Q: Which standards govern thickness measurements?

Use ISO 19840 or SSPC-PA 2/ASTM D7091 for DFT, and ASTM D4414 for WFT. Calibration certificates must be current.

Q: When should stripe coats be applied?

Before full coats on edges, welds, bolt heads, and other sharp details to ensure adequate film build and durability.

Q: Is adhesion testing always required?

Adhesion testing frequency is defined in the ITP or project spec. Typical practice is representative pull-off tests; verify acceptance values with the manufacturer/specifications.

More than a static template

Unlike a downloadable Word or PDF template, this method statement is an AI-assisted editable starting point connected directly to a matching Inspection and Test Plan. Every section is structured, project-adaptable, and ready to export.

AI-assisted drafting — Customize every section with AI for your specific project scope.
Linked ITP — A matching inspection and test plan is generated alongside the method statement.
Multiple export formats — Download as a formatted PDF or editable Excel spreadsheet.
Editable starting point, not a final document — Review, verify, and adjust all content against your project requirements before use.

Static template vs. Quollnet workflow

Feature	Static template	Quollnet
Project-specific content	Manual fill-in required	AI-assisted customization
Linked ITP	Separate document, no link	Matching ITP included
Export formats	Usually PDF only	PDF and Excel
Structured sections	Free-form layout	13 standardized sections
Saved to your account	Local file only	Cloud-saved, reusable
Content accuracy	You verify everything	AI-assisted, you still verify
Cost	Often free but time-intensive	Free to customize and download

What you can customize

When you save this method statement to your account, every section becomes editable. The following 13 sections are included:

Scope — Defines the activity and its boundaries.
References — Standards, specifications, and drawings.
Responsibilities — Roles and accountabilities.
Resources — Labour, plant, and equipment summary.
Materials — Materials and compliance requirements.
Equipment — Tools and equipment details.
Prerequisites — Hold points and pre-conditions.
Method sequence — Step-by-step construction sequence.
Safety controls — HSE risk controls and PPE.
Environmental controls — Environmental mitigation measures.
QA/QC — Quality inspection and test requirements.
ITP — Inspection and Test Plan table (has its own page).
Attachments — Referenced drawings and documentation.

Why this method statement is used

This method statement is used to define and communicate the approved procedure for carrying out method statement – intumescent paint application to structural steelwork on site. It ensures the work is planned in advance, the correct resources and controls are in place, and all personnel understand responsibilities, sequence, quality requirements, and safety controls before work begins. It aligns site execution with the documented scope and acceptance expectations.

Who uses this method statement

This method statement is used by contractors, site supervisors, project engineers, QA/QC engineers, HSE officers, consultants, and client representatives. It serves as a shared reference for planning, execution, supervision, inspection, and approval of the activity on site.

When it is prepared and submitted

The method statement is prepared before the work activity starts and submitted as part of the pre-construction documentation package for review and approval.

Who reviews or approves it

The method statement is usually submitted to the client representative, consultant, resident engineer, or project management consultant for review and approval before the work commences.

Important approval note

This method statement is an AI-assisted editable starting point, not a pre-approved document. Before use on any project, all content must be reviewed and approved by the relevant parties (superintendent, principal contractor, or client representative) in accordance with your contract and project quality plan.

For example: if your specification requires a departure from a referenced standard, that departure must be documented and approved separately — this method statement will not capture that automatically. Always verify against your applicable drawings, specifications, and regulatory requirements.

Method statement content

Scope of Works

Overview

This method covers the complete process for application of intumescent paint systems to structural steelwork, including: surface preparation to Sa 2½; verification of surface profile and contamination; compatible primer application; intumescent basecoat application with wet film and dry film thickness (WFT/DFT) control; stripe coats to edges, welds, and bolt arrays; environmental monitoring; curing; adhesion testing; topcoat/sealer application; repair of defects; and QA/QC records.

Included Elements

Primary and secondary structural steel members (beams, columns, braces, trusses, plate girders, connections).
Shop or site application (as specified).
Protection to achieve the fire resistance rating per the Fire Engineering design and manufacturer’s calculations.

Exclusions

Passive fire protection by boards, spray plasters, or cementitious systems.
Structural repairs or alterations to steelwork.

Key Objectives

Achieve the specified fire rating with verified intumescent DFT per member based on section factor (Hp/A) and exposure type.
Deliver a coating system free from runs, sags, pinholes, cracks, and contamination, with documented traceability and inspection records.

References and Standards

Document Type	Reference / Number	Revision	Notes
Standard	ISO 8501-1: Preparation of steel substrates – Visual assessment of surface cleanliness (Sa 2½).
Standard	ISO 8502 (series): Tests for surface cleanliness – including ISO 8502-3 (dust), ISO 8502-4 (dew point), ISO 8502-6/9 (Bresle method for soluble salts).
Standard	ISO 8503 (series): Surface roughness characteristics of blast-cleaned steel substrates.
Standard	ISO 19840 / SSPC-PA 2 / ASTM D7091: Measurement of DFT on ferrous substrates (sampling and acceptance).
Standard	ASTM D4414: Measurement of wet film thickness by notch gauges.
Standard	ASTM D4541 / ISO 4624: Pull-off strength (adhesion) of coatings.
Standard	ISO 12944 (relevant parts): Corrosion protection of steel structures by protective paint systems (edge preparation, durability concepts).
Standard	SSPC-SP 1: Solvent Cleaning.
PDS/SDS	Manufacturer’s Product Data Sheets (PDS) and Safety Data Sheets (SDS) for primer, intumescent basecoat, and topcoat.
Project Document	Project Specifications, Fire Strategy Report, and Intumescent Thickness Calculation Sheets per member (Hp/A, critical DFT).

Responsibilities

Role	Responsibility	Name / Party
Project Manager	Overall delivery, resources, approvals, programme integration, coordination with Fire Engineer and Architect.
Construction/Site Engineer	Setting out, access/containment planning, environmental monitoring, daily interface with inspectors and applicators.
QA/QC Manager	Inspection/Test coordination, ITP implementation, NCR/CAR management, records compilation, final dossier.
Coating Inspector (AMPP/NACE Level 2 or equivalent)	Hold/witness inspections, surface cleanliness/profile checks, WFT/DFT verification, adhesion testing oversight, acceptance sign-off.
Painting Supervisor	Execution planning, crew briefings, method adherence, mixing/application control, recoat/cure management, repairs.
HSE Manager/Officer	Task-specific risk assessments, permits, ventilation, monitoring of VOC/isocyanate exposure [Verify per project HSE plan], emergency preparedness.
Procurement/Materials Controller	Batch traceability, storage per PDS, shelf-life control, delivery of calibrated gauges and test kits.
Third-Party Inspector (if specified)	Independent verification at hold points per ITP and contract.

Resources (Manpower)

Resource Type	Description	Quantity	Remarks
		2–4 [Verify per scope]
		3–6 [Verify]
		2–3
		1
		1
		2–4
		As required

Materials

Material	Specification / Grade	Quantity	Remarks
Degreaser/Solvent (SSPC-SP1 compliant)	Non-residue, compatible with subsequent coating.
Abrasive Media (e.g., Garnet 30/60)	Clean, dry, free from contaminants; profile target 40–75 µm Rz [Verify per PDS].
Compatible Primer (e.g., epoxy zinc phosphate or zinc-rich/epoxy as approved)	Manufacturer-approved for intumescent; typical DFT 50–75 µm [Verify].
Intumescent Basecoat (water-borne/solvent-borne/epoxy intumescent)	Selected to meet required fire rating; supplied with manufacturer’s thickness schedule per Hp/A [Verify].
Stripe Coat Material	Same intumescent basecoat or compatible primer as per manufacturer’s guidance.
Sealer/Topcoat (if specified)	UV/weathering protection; manufacturer-approved and compatible; typical DFT 40–60 µm [Verify].
Thinners/Cleaners	As per PDS; controlled use only.
Masking/Protection	Poly sheeting, tape, tarps for overspray containment.

Equipment

Equipment	Capacity / Type	Quantity	Inspection Required
Abrasive Blasting Pot & Nozzles	Nozzle size 6–8 mm; moisture separator and air dryer required.
Air Compressor	>= 250 cfm with aftercooler/dryer [Verify].
Dust Extraction/Containment	Vacuum recovery or enclosure with filters to control emissions.
Airless Spray Pump	45:1–68:1 ratio, min 4–6 L/min; tip 0.027–0.035 in for intumescent [Verify per PDS].
Mixers (Paddle/High-torque)	For uniform dispersion; timer for mixing duration per PDS.
Hygrometer/Dew Point Meter	Measures air temp, RH, dew point; with calibration certificate.
Infrared Thermometer/Contact Thermometer	Substrate temperature readings.
WFT Gauges (ASTM D4414)	Notched comb type; suitable for high-build coatings.
DFT Gauge (ISO 19840/ASTM D7091)	Magnetic induction/eddy current; current calibration certificate.
Bresle Kits & Conductivity Meter	ISO 8502-6/9 soluble salt testing.
Dust Tape Test Kit	ISO 8502-3 assessment cards.
Surface Profile Replica Tape/Profilometer	ISO 8503 measurement.
Access Equipment	Certified scaffolding, MEWPs with fall protection.
Ventilation/Extraction Fans	Maintain safe solvent vapor levels and drying conditions.
Lighting	500–1000 lux in containment areas for inspection.
PPE & Safety Gear	Air-fed respirators (as needed), gloves, coveralls, eye and hearing protection.

Prerequisites

Approvals and Submittals

Approved Method Statement, ITP, Risk Assessment/Method Statement (RAMS).
Manufacturer approvals: primer, intumescent, topcoat compatibility letters.
Fire design calculations: Hp/A, target DFT per member and fire rating, coating schedule.
Calibration certificates for all gauges and meters (within validity).

Site Readiness

Access and containment installed; ventilation plan verified.
Ambient condition control feasible (heating/dehumidification if required).
Substrate free from fabrication oils; welds inspected and accepted.
Edges prepared to a minimum 2 mm radius where practicable to improve coating retention [Verify per project specs/ISO 12944 guidance].
Protection to adjacent finishes and equipment installed.

Training & Trials

Toolbox talk for spraying hazards, injection injury, confined spaces, isocyanates (if applicable).
Mock-up/panel trial to confirm finish and achievable WFT/DFT (if specified).

Hold/Witness Points

Pre-blast inspection; post-blast before priming; pre-intumescent; post-DFT each coat; adhesion test; final acceptance.

Method Sequence

Step	Activity	Description	Responsibility	Inspection / Hold Point
1	Receipt, Storage, and Batch Control	Receive materials with COAs/SDS. Store between manufacturer’s min/max temperatures (e.g., 5–30°C) and off the floor; rotate stock FIFO. Record batch/expiry on Material Control Log.	Materials Controller / QA/QC	Visual; temperature log
2	Surface Degreasing	Remove oil/grease per SSPC-SP1 using approved degreaser; rinse/wipe dry. Verify no residues.	Painting Supervisor	Random wipe test/visual
3	Abrasive Blasting to Sa 2½	Blast clean to ISO 8501-1 Sa 2½ with angular profile 40–75 µm Rz [Verify per PDS]. Maintain clean, dry compressed air. Contain and collect abrasive.	Blasting Supervisor	Visual comparator vs ISO 8501-1; profile measurement ISO 8503
4	Surface Cleanliness Testing	Check dust (ISO 8502-3, max Class 2 quantity/size [Verify]); soluble salts via Bresle (ISO 8502-6/9, ≤20 mg/m² chloride as NaCl [Verify]).	Coating Inspector	Dust tape test; conductivity conversion to mg/m²
5	Environmental Check (Pre-Prime)	Record air temp, RH, dew point, steel temp. Ensure steel temp ≥ 3°C above dew point; RH ≤ 85% [Verify].	Coating Inspector	Hygrometer/dew point meter
6	Primer Application	Apply compatible primer to target DFT 50–75 µm [Verify] within allowable window post-blast (typically ≤4 hours or before visible rusting).	Painting Supervisor	WFT checks ASTM D4414; DFT checks per ISO 19840/ASTM D7091
7	Primer Cure & Recoat Window	Allow to cure per PDS (time/temp/RH). If exceeded recoat window, abrade/clean as per PDS before intumescent.	Painting Supervisor	Time/ambient log; surface cleanliness
8	Stripe Coats to Details	Brush-apply stripe coats to edges, welds, bolt heads, stiffeners using same intumescent basecoat or as specified by manufacturer.	Painting Supervisor	Visual coverage; WFT spot checks
9	Intumescent Basecoat – First Pass	Confirm target total DFT per member from approved schedule (often 1.0–3.5 mm for 60–120 min ratings) [Verify]. Apply by airless spray in multiple passes; do not exceed per-coat WFT per PDS (typ. 800–1500 µm). Avoid runs/sags.	Painting Supervisor	WFT checks; visual for defects; ambient log
10	Curing Between Coats	Allow each coat to reach minimum recoat condition per PDS (time/temp/RH/ventilation). Confirm surface is firm, non-tacky, and supports subsequent coats without damage.	Painting Supervisor	Touch/visual; time/ambient records
11	Subsequent Intumescent Coats	Repeat application/inspection cycles until scheduled total DFT achieved for each member. Maintain identification and mapping of readings per member/face.	Painting Supervisor / Coating Inspector	DFT per ISO 19840 sampling; map and record
12	Adhesion Testing (Representative Areas)	Perform pull-off adhesion tests (ASTM D4541 or ISO 4624) at agreed frequency (e.g., 1 test per 500 m² or per 50 members, min 3 tests) [Verify]. Repair dollies locations after test.	Coating Inspector	Pull-off tester; record MPa and failure mode
13	Repairs and Touch-ups	Address low DFT by additional coats. For runs/sags/mud cracking: sand back or remove to sound layer and reapply per PDS. Feather edges; re-measure DFT.	Painting Supervisor	DFT re-check; visual finish
14	Topcoat/Sealer (If Specified)	Apply compatible sealer/topcoat within recoat window after basecoat fully cured. Typical DFT 40–60 µm [Verify]. Confirm gloss/colour if architectural.	Painting Supervisor	WFT/DFT; compatibility confirmation
15	Final Inspection and Handover	Comprehensive DFT mapping, adhesion results, environmental logs, batch traceability, NCR close-outs, manufacturer’s compliance letter (if required). Protect finished works.	QA/QC Manager / Coating Inspector	Document review; visual walkthrough

Health & Safety Controls

Task-Specific Hazards and Controls

Hazard: Abrasive blasting dust and rebound.
Consequence: Respiratory injury, eye injury, silicosis (if improper media), skin lacerations.
Engineering/Procedural Control: Use low-dust garnet; enclosed/curtained blasting with dust extraction; deadman controls; trained operators; exclusion zones.
PPE: Blast hood with Grade D breathing air; gloves; cut-resistant coveralls; hearing protection; safety boots.
Collective Measure: Negative-pressure containment with filtration; debris netting.
Inspection/Permit/Supervision: Containment integrity checks; compressor moisture traps inspected daily; HSE supervision.
Hazard: Solvent/flammable vapors from coatings and thinners.
Consequence: Fire/explosion, toxic exposure.
Engineering/Procedural Control: Use intrinsically safe lighting/ventilation; eliminate ignition sources; decant in ventilated areas; bonding/earthing of containers; hot-work exclusion.
PPE: Chemical-resistant gloves; goggles/face shield; organic vapor respirators or air-fed respirators as required by SDS.
Collective Measure: Mechanical ventilation achieving target air changes; LEL monitoring where warranted.
Inspection/Permit/Supervision: Flammable liquids storage per approved cabinets; daily LEL/ventilation checks; permit-to-work for confined/controlled areas [Verify per project HSE plan and local regulations].
Hazard: Isocyanate exposure (certain polyurethane topcoats).
Consequence: Sensitization, asthma.
Engineering/Procedural Control: Substitute non-isocyanate where possible; otherwise, closed spray systems, ventilation, restricted access.
PPE: Air-fed respirator; chemical coveralls; nitrile gloves.
Collective Measure: Health surveillance/fit testing.
Inspection/Permit/Supervision: SDS review; exposure monitoring as required by law [Verify].
Hazard: High-pressure airless spray injection injury.
Consequence: Tissue necrosis/amputation.
Engineering/Procedural Control: Tip guards, trigger locks, safe distance, do not wipe tips under pressure; emergency response plan with immediate hospital referral.
PPE: Gloves, goggles/face shield, coveralls.
Collective Measure: Exclusion zones; equipment lockout/tagout for maintenance.
Inspection/Permit/Supervision: Daily equipment inspection; operator training records; supervisor sign-off.
Hazard: Working at height on steel frames.
Consequence: Falls leading to serious injury/fatality.
Engineering/Procedural Control: Certified scaffolds/MEWPs; double lanyard fall arrest; edge protection; tethered tools.
PPE: Full-body harness with shock-absorbing lanyard; helmet with chinstrap.
Collective Measure: Guardrails and toe boards; rescue plan.
Inspection/Permit/Supervision: Pre-use checks; statutory scaffold inspections; MEWP operator certification.
Hazard: Noise and vibration from blasting/compressors.
Consequence: Hearing loss, HAVS.
Engineering/Procedural Control: Selection of quieter plant; isolation; exposure time management.
PPE: Hearing protection (SNR per noise map).
Collective Measure: Acoustic screens where feasible.
Inspection/Permit/Supervision: Noise surveys; health surveillance per regulations.
Hazard: Confined/poorly ventilated spaces (enclosures).
Consequence: Asphyxiation, solvent overexposure.
Engineering/Procedural Control: Confined space assessment; forced ventilation; gas monitoring; standby attendant.
PPE: Respiratory protection per monitoring results.
Collective Measure: Permit-to-work with rescue plan.
Inspection/Permit/Supervision: Confined Space Permit; continuous monitoring.
Hazard: Manual handling of drums and equipment.
Consequence: Musculoskeletal injuries.
Engineering/Procedural Control: Use drum trolleys/hoists; team lifts; decant to smaller containers.
PPE: Gloves, safety footwear.
Collective Measure: Mechanical aids.
Inspection/Permit/Supervision: Supervisor to enforce lift plans.
Hazard: Electrical equipment in damp/paint environments.
Consequence: Electric shock.
Engineering/Procedural Control: 110V center-tapped transformers or RCDs; IP-rated equipment; cable management.
PPE: Dielectric gloves as needed; dry gloves.
Collective Measure: PAT testing.
Inspection/Permit/Supervision: Daily visual checks; formal inspections per schedule.

Environmental Controls

Controls for Environmental Impact

Dust and Abrasive Containment: Fully enclose blasting zones with sheeting; use vacuum recovery. Daily cleanup; prevent migration to drains.
Waste Management: Segregate spent abrasive and paint debris as potentially hazardous waste; test and dispose per licensed facility requirements. Maintain waste transfer notes.
VOC and Odor Management: Choose low-VOC options where feasible; mechanical ventilation to maintain concentrations below occupational limits; schedule high-VOC works off-peak.
Overspray and Drift: Use shrouds, windscreens, and correct tip/pressure; halt spraying above safe wind thresholds [Verify per site limit].
Noise: Fit silencers; schedule noisy tasks during permitted hours; provide acoustic barriers as needed.
Water Protection: Block stormwater inlets near work; deploy spill kits; prohibit washing tools into drains.
Energy Efficiency: Use properly sized compressors with dryers; shut down idling equipment.
Material Efficiency: Mix only required quantities; track pot life to reduce waste.

QA/QC Requirements

Inspection and Testing

Implement ITP with defined hold/witness points.
Calibration: DFT/WFT gauges, hygrometers, conductivity meters, and pull-off testers with valid certificates.
Sampling Frequency (typical) [Verify per ITP/spec]:
DFT: per ISO 19840/SSPC-PA 2 – e.g., min 5 measurement areas per 10 m² or per member flange/web; each area = ≥3 gauge readings.
Salts: at least 1 Bresle test per 50 m² per shift per substrate condition change.
Dust: at least 1 test per 50 m².
Adhesion: 1 set per 500 m² or per 50 members, min 3 pulls.

Acceptance Criteria (typical – verify project/manufacturer)

Cleanliness: ISO 8501-1 Sa 2½, free from visible dust/oil/grease.
Salts: ≤20 mg/m² chloride as NaCl (Bresle) [Verify].
Dust: ISO 8502-3 max Class 2 (quantity/size) [Verify].
Profile: 40–75 µm Rz [Verify].
Primer DFT: 50–75 µm, uniform; within manufacturer’s limits for overcoating.
Environmental: Steel temp ≥3°C above dew point; RH ≤85%; substrate/application temperatures within PDS.
Intumescent DFT: Per approved schedule; acceptance per ISO 19840/SSPC-PA 2 – mean ≥ NDFT; no individual reading <80% NDFT unless otherwise permitted by standard/manufacturer [Verify].
Adhesion: ≥1.5 MPa average; no individual <1.0 MPa; predominantly cohesive failure in coating or adhesive acceptable [Verify/manufacturer].

Documentation and Traceability

Coating Inspection Reports (CIRs), DFT maps per member, WFT logs, environmental logs, salt/dust/profile records, adhesion test reports.
Batch records (primer/intumescent/topcoat), COAs/SDS, equipment calibration.
NCR/CARs and corrective actions; final MDR/hand-over dossier with manufacturer’s compliance letter (if required).

Attachments

Approved product data sheets and SDS for primer/intumescent/topcoat.
Coating schedule by member (Hp/A, required DFT and fire rating).
DFT maps and WFT logs.
Environmental monitoring logs.
Bresle salt test and dust test records.
Surface profile measurement records.
Adhesion test reports with locations and photos.
Equipment calibration certificates.
Material batch and storage logs.
NCR/CAR register and close-out evidence.
Manufacturer’s compatibility/approval letters and any site visit reports.

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ITP preview

The first inspection activities from the linked ITP for Method Statement – Intumescent Paint Application to Structural Steelwork:

Activity	Inspection / Test	Acceptance Criteria	Responsibility	Record
Material receipt and storage	Verify PDS/SDS, batch numbers, shelf-life, storage temperatures	Conforms to approved submittals; storage within PDS limits; no damaged containers	QA/QC + Materials Controller	Material Receipt & Storage Log
Surface degreasing (pre-blast)	Visual and wipe test per SSPC-SP1	No oil/grease residues; clean, dry surface	Coating Inspector	Pre-blast Inspection Report
Abrasive blasting	Visual vs ISO 8501-1; profile ISO 8503	Sa 2½; profile 40–75 µm Rz [Verify]	Coating Inspector	Post-blast Report; Profile Measurements

Showing 3 of 15 inspection activities. View full ITP →

Related Inspection and Test Plan

An Inspection and Test Plan (ITP) is available for Method Statement – Intumescent Paint Application to Structural Steelwork. The ITP defines the inspection activities, acceptance criteria, hold and witness points, responsible parties, and records required to verify the work described in this method statement.

View the Method Statement – Intumescent Paint Application to Structural Steelwork ITP →

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