What is Interchar 404 and why choose it
Interchar 404 from International Marina is a one-component, solvent-based, high-solids acrylic intumescent coating designed to deliver fire protection for structural steel. Independently tested in accredited laboratories in accordance with EN 13381-8 and CE marked with European Technical Approval ETA-09/0259, it offers up to 2 hours of fire protection on a wide range of steel sections. Its fast drying and rapid recoatability make it suitable for application in steel fabrication shops over approved priming systems for both interior and exterior use.
Main features
- High-performance intumescent protection: Provides up to 2 hours fire protection on I-section beams, columns and hollow sections.
- One-component, high-solids system: Solvent-borne acrylic intumescent with 75% ± 2% volume solids, simplifying mixing and reducing applied coats compared to low-solids products.
- Fast drying and rapid recoatability: Typical touch-dry time from 20 to 60 minutes depending on temperature, with short minimum overcoating intervals to accelerate fabrication schedules.
- Certified performance:
- Tested in accordance with EN 13381-8 for structural steel fire protection.
- CE marked with European Technical Approval ETA-09/0259.
- Versatile application: Designed for airless spray application, with brush use recommended for small areas and repairs.
- Wide primer and topcoat compatibility: Approved over multiple anti-corrosive primers and with several finishing coats for complete coating systems.
- Interior and certain exterior exposure: Can be used internally and externally when correctly sealed; a more water-resistant variant is available for limited unsealed exterior exposure (ISO 12944 C2, up to 6 months, without pooling water or frequent high humidity).
- Available colours and finish: Supplied in white and grey, with a matt appearance.
Key technical characteristics
Coating data
- Chemistry: Acrylic intumescent, solvent-borne, one component.
- Colour: White, Grey.
- Gloss level: Matt.
- Volume solids: 75% ± 2%.
- Recommended dry film thickness (per coat): 200–1000 microns (8–40 mils) dry, equivalent to 267–1333 microns (10.7–53.3 mils) wet.
- Theoretical coverage:
- 1 m²/litre at 750 microns DFT with stated volume solids.
- 40 sq.ft/US gallon at 30 mils DFT with stated volume solids.
- Practical coverage: Allow appropriate loss factors.
Drying and overcoating times (typical at 750 microns DFT)
- 10°C (50°F): Touch dry 60 minutes; hard dry 24 hours; minimum overcoating with self 9 hours; maximum overcoating extended.
- 15°C (59°F): Touch dry 60 minutes; hard dry 22 hours; minimum overcoating 7 hours; maximum overcoating extended.
- 25°C (77°F): Touch dry 40 minutes; hard dry 18 hours; minimum overcoating 5 hours; maximum overcoating extended.
- 40°C (104°F): Touch dry 20 minutes; hard dry 8 hours; minimum overcoating 3 hours; maximum overcoating extended.
The sealer coat should be applied as soon as possible after completion of the final Interchar 404 coat (minimum 2–4 hours for Intersheen 579, 24 hours for Interthane or Interfine sealers). The applied dry film thickness must be checked to confirm that the specified thickness has been achieved before sealing.
Regulatory and physical data
- Flash point (typical): 5°C (41°F).
- Product weight / density: 1.37 kg/l (approx. 1.365 g/cm³).
- VOC content: 237 g/kg (EU Solvent Emissions Directive 2010/75/EU).
- Boiling point: 111°C (231.8°F).
- Viscosity: Kinematic 2371 mm²/s at room temperature; 3236 mm²/s at 40°C (DIN EN ISO 3219).
- Water solubility: Not soluble in cold water (OECD TG 105).
- Shelf life: Minimum 12 months at 25°C (77°F), subject to re-inspection thereafter; store in dry, shaded conditions away from sources of heat and ignition.
- Pack size: 20 litre units (typical shipping weight 27.4 kg per 20 L pack).
Application guidelines (summary)
- Surface preparation:
- All surfaces must be clean, dry and free from contamination.
- Assess and prepare surfaces in accordance with ISO 8504.
- Remove oil and grease in accordance with SSPC-SP1 solvent cleaning.
- Apply Interchar 404 only over recommended anti-corrosive primer schemes; primer must be dry, of normal appearance and within its overcoating interval.
- Areas of breakdown or damage: prepare to Sa2½ (ISO 8501-1:2007) or SSPC SP6 abrasive blast, or SSPC SP11 power tool cleaning, then patch-prime before applying Interchar 404.
- On metallic zinc primers: ensure surface is clean, dry and free from zinc salts; primers must be fully cured. A tie coat (typically Intergard 269 or Intergard 276) is recommended to prevent zinc salt accumulation.
- Mixing: One-component product; mix thoroughly using a power agitator before application.
- Recommended application methods:
- Airless spray: Recommended for achieving maximum film build in a single coat.
- Tip size range: 0.48–0.59 mm (19–23 thou).
- Minimum fluid pressure at tip: 246 kg/cm² (3498 psi).
- Recommended hose: 9.0 mm (3/8") bore with 6.5 mm (1/4") whip end.
- Brush: Suitable for small areas and repairs; multiple coats may be needed to reach specified dry film thickness.
- Conventional air spray (pressure pot): Not recommended.
- Roller: Not recommended.
- Thinning: Thinner normally not required.
- Cleaning solvent: International GTA007 for flushing and cleaning all equipment.
- Application conditions:
- Surface temperature must be at least 3°C above dew point.
- Ensure adequate ventilation, especially in confined spaces.
- Avoid mixing application methods on the same surface where possible, as this affects the final appearance.
- Over-application increases minimum overcoating intervals and handling times.
- Water exposure:
- Interchar 404, sealed or unsealed, must be protected from pooling or running water.
- Not designed for frequent water immersion or soaking.
- A higher water-resistance version is available to allow unsealed exterior exposure up to 6 months in ISO 12944 C2 environments, provided there is no pooled or heavy running water or frequent high humidity.
System compatibility
Interchar 404 has been tested as part of fire protection coating systems over a broad range of approved primers and topcoats.
Approved primers for use with Interchar 404
- Intercure 200
- Intercure 200HS
- Intergard 251
- Intergard 251HS (where specified)
- Intergard 269
- Intergard 2509
- Interplate 398
- Interprime 306
- Interseal 670HS
- Interseal 1052
- Interzinc 42
- Interzinc 52
Approved topcoats for use over Interchar 404
- Intersheen 579
- Interthane 870
- Interthane 990
- Interthane 990SG
When used in accordance with the European Technical Approval, the surface preparation, primer and topcoat must follow the specification defined in the approval and be approved by International Protective Coatings. Where a polysiloxane topcoat is envisaged, a tie coat must be applied over Interchar 404 following the applicable application guidelines.
Typical applications and use cases
- Structural steel fire protection: Up to 2 hours fire resistance on I-section beams, columns and hollow sections used in buildings and industrial structures.
- Steel fabrication shops: Fast drying and rapid overcoating enable efficient application during fabrication before erection.
- Projects requiring certified systems: Applications where EN 13381-8 tested performance and CE marking with ETA-09/0259 are specified.
- Interior and selected exterior environments: When combined with approved primers and topcoats, suitable for interior and, when correctly sealed or using the water-resistant variant, for defined exterior conditions (ISO 12944 C2, limited exposure).
FAQ – Interchar 404
-
What type of fire protection does Interchar 404 provide?
Interchar 404 is an intumescent coating that expands under fire exposure to insulate structural steel, providing up to 2 hours of fire protection on I-section beams, columns and hollow sections when applied to the specified thickness.
-
Can Interchar 404 be applied directly to bare steel?
No. It should always be applied over a recommended anti-corrosive primer scheme. Bare steel must be prepared to the specified standard, primed, and then overcoated with Interchar 404 within the primer’s overcoating interval.
-
Which application method is preferred?
Airless spray is recommended to achieve maximum film build in a single coat and obtain the best finish on visible areas. Brush application is suitable only for small areas and repairs.
-
Is Interchar 404 suitable for exterior use?
Interchar 404 can be used externally when correctly sealed within an approved system. A higher water-resistance version is available for unsealed exterior exposure up to 6 months in ISO 12944 C2 environments with no pooled water or frequent high humidity.
-
How soon can I apply a sealer or topcoat?
For Intersheen 579 sealer, wait a minimum of 2–4 hours after the final Interchar 404 coat. For Interthane or Interfine sealers, wait at least 24 hours. Always verify that the specified dry film thickness of Interchar 404 has been achieved before sealing.
-
Do I need to thin Interchar 404?
Thinner is not normally required. If cleaning is needed, use International GTA007 for equipment flushing and clean-up.
-
What is the recommended storage condition and shelf life?
Store unopened containers in a dry, cool, well-ventilated place, away from heat, ignition sources and oxidizing materials. At 25°C (77°F) the shelf life is at least 12 months, subject to re-inspection thereafter.
-
Can Interchar 404 be immersed in water or used in permanently wet conditions?
No. Interchar 404 is not designed for frequent water immersion or soaking, and the coating (sealed or unsealed) must be protected from pooling or running water.
-
What cleaning procedure is recommended for equipment?
Thoroughly flush all application equipment with International GTA007 after use. During the working day, periodically flush spray equipment depending on volume sprayed, temperature and any delays.
-
Who should apply Interchar 404?
The product is intended for use only by professional applicators in industrial situations, following the Safety Data Sheet, technical data sheet and relevant regulations.
Section 14 – Transport information
- UN number / ID number: UN1263.
- UN proper shipping name: PAINT.
- Transport hazard class: Class 3 (flammable liquid).
- Packing group: II.
- Environmental hazards: Not classified as environmentally hazardous for transport (ADR/RID, IMDG, IATA: No).
- ADR/RID special provisions: Special provisions 640 (C); Tunnel code (D/E).
- IMDG emergency schedules: EmS F-E, S-E.
- Special precautions for user: Within user’s premises, transport only in closed containers kept upright and secure. Ensure personnel involved in transport know the actions to take in case of accident or spillage.
- Transport in bulk according to IMO instruments: Not applicable.
Section 8 – Personal protection measures
The following measures are derived from the Safety Data Sheet and apply to professional and industrial use. A task-specific risk assessment must always be carried out before work.
Exposure controls
- Engineering controls:
- Use only with adequate ventilation.
- Apply local exhaust ventilation, process enclosures or other engineering controls to keep airborne concentrations below statutory limits and below lower explosive limits.
- Use explosion-proof ventilation equipment.
- Hygiene measures:
- Prohibit eating, drinking and smoking in areas where the product is handled or stored.
- Wash hands, forearms and face thoroughly after handling and before eating, smoking or using the lavatory.
- Remove contaminated clothing and protective equipment before entering eating areas; wash contaminated clothing before reuse.
- Ensure eyewash stations and safety showers are available near work areas.
Individual personal protective equipment (PPE)
- Eye and face protection:
- Wear chemical splash goggles complying with an approved standard whenever there is a risk of liquid splashes, mists, gases or dusts.
- Hand protection:
- Use chemical-resistant, impervious gloves meeting EN374 or equivalent when handling the product.
- For prolonged or frequently repeated contact, use gloves with protection class 6 (breakthrough time > 480 minutes according to EN374). Recommended: Viton or nitrile, thickness ≥ 0.38 mm.
- For brief contact, use gloves with protection class ≥ 2 (breakthrough time > 30 minutes according to EN374). Recommended: nitrile, thickness ≥ 0.12 mm.
- Replace gloves regularly and immediately if damaged. Performance can be reduced by physical or chemical damage or poor maintenance.
- Body protection:
- Select protective clothing based on the tasks and associated risks, and have it approved by a specialist.
- Where there is risk of ignition from static electricity, wear anti-static protective clothing. For maximum protection, use anti-static overalls, boots and gloves (see EN 1149 for requirements and test methods).
- Other skin protection:
- Use appropriate footwear and additional skin protection measures based on task-specific risks and specialist advice.
- Respiratory protection:
- Where ventilation is insufficient, wear a respirator conforming to EN140 with type A/P2 filter or better, selected as part of a formal respiratory protection programme.
- Dry sanding, flame cutting or welding of the dry paint film produces hazardous dusts and fumes; use wet methods where possible and, if exposure cannot be avoided, wear suitable respiratory protection.
Environmental exposure controls
- Check emissions from ventilation and process equipment to ensure compliance with environmental legislation.
- Where necessary, use fume scrubbers, filters or engineering modifications to reduce emissions to acceptable levels.
*Contenido generado por IA
