Nullifire SC804 On-Site Water-Based Intumescent Basecoat is a water-based, white, thin film intumescent coating for the protection of internal structural steelwork, developed to give optimised loadings for up to 90 minutes, and up to 120 minutes fire resistance.
SC804 is a water based intumescent coating used for internal structural steel to C1 and C2 environments; the coating can then be top coated with a suitable topcoat for decorative and durability purposes. If SC804 is to be used on exterior exposed steelwork, it must be top coated prior to exposure, and care taken that no standing or pooling water is allowed to accumulate.
SC804 can be applied to a smooth matt finish. A compatible top seal can be applied if a decorative finish is required.
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Features & Benefits
- Anti-fire coating for use on internal structural steelwork
- Intumescent fire protection
- Developed to give optimised loadings for up to 90 minutes
- Up to 120 minutes fire resistance
- Used in C1 and C2 environments
- Water based
- Can be top coated with a suitable topcoat for decorative and durability purposes
- If used on exterior exposed steelwork, it must be top coated prior to exposure
- No standing or pooling water is allowed to accumulate.
- Supplied ready to use - no need for mechanical agitation and must not be thinned
- Apply by spray, brush or roller
- Ultra Low VOC
- Competitive loadings
- Compatible with a wide range of primers and topcoats
- Excellent aesthetics
- Loading Tables available to download
Usage Guidelines
Use in well ventilated conditions and ensure all recommended protective equipment is worn during handling & use of this product. For full recommendation, refer to the safety data sheet.
Substrate Preparation
- SC804 should be applied onto a clean, undamaged and dry primed surface
- Nullifire recommended primers are listed on the ETA and Nullifire’s website.
- Nullifire have carried out compatibility testing on a wide range of primers and topcoats and can be contacted on 0203 917177 for confirmation of compatibility with SC804 - or contact our Technical team on 0113 2455450 (option 2) or send a message to [email protected].
- The primer must be applied in accordance with the manufacturer’s instructions.
Application Conditions
- SC804 is recommended for application and use on dry protected structural steel only.
- If the basecoat is allowed to get wet, it is likely to be damaged – blistering and wrinkling may occur.
- SC804 should only be applied when the air and steel temperatures are above 5°C. Relative humidity should be below 80% for successful application. Steel surface temperature should be a minimum of 3°C above the dew point.
- Ensure the steel is dry and free from contact with rain or condensation during the application and drying of SC804.
Application Equipment
Airless spray equipment is recommended and should match these guidelines:
- Operating Pressure: 2500 - 3000 psi (175 210 kg/cm²)
- Tip Size: 17 – 21 thou
- Fan Angle: 20° – 40°
- Hose Diameter: 10 mm (3/8”) (internal diameter)
- Hose Length: Max. 60 metres, in-line filters should not normally be used.
Mixing
SC804 is supplied ready for use and must not be thinned prior to use. Mechanical agitation is not necessary prior to use.
Application
Loading Tables are available (click to download).
Airless Spraying
- SC804 may be applied up to a maximum wet film thickness (WFT) of 1.0 mm in a single spray coat comprising of several quick passes. Achieving maximum loadings will depend on site conditions.
- The vast majority of 60 minute loadings can be applied in single coat.
Brush/Roller Application
- For brush application use a “laying on” technique to avoid heavy brush marking.
- Maximum wet film per coat when applied using a brush or roller is 0.6 mm. A short piled roller will produce a light textured finish.
- During application, measure the wet film thickness frequently with a WFT gauge to ensure the correct thickness is being applied.
- To use the gauge, insert the teeth into the wet basecoat. The last tooth to be coated indicates the wet film thickness achieved.
- In the event of over or under applications, adjustments to the loading rates of subsequent coats will be required.
Drying Times
|
Temperature |
| WFT |
10°C |
20°C |
30°C |
| 0.2mm |
3h |
2h |
1h |
| 0.5mm |
4h |
3h |
2h |
| 1.0mm |
6h |
4h |
3h |
These are times for a typical mid-range humidity and good air flow. Higher humidity, poor airflow or overnight condensation will all lengthen these times. Recommended overcoat time is 16 hours. Do not over coat if the surface is not touch dry. Check web-flange joints.
Application Advice
The following instructions are for on-site application only. For off-site application, refer to Nullifire/Rawlins Technical. Ensure that:
- The primer is compatible with SC804 and has been applied correctly.
- The overcoating period for the primer has not been exceeded.
- The correct primer is used for galvanised steel.
- All damage to the primer has been repaired & re-primed.
- Site and weather conditions are within specification.
- SC804 has been stored correctly.
- Surface is clean, dry and free from contamination.
- Correct spray equipment is available, if appropriate.
- Application instructions have been read prior to commencement of work.
- Ensure different basecoats are not applied on the same section of steel.
- Equipment should be clean and free from contaminants or dried material.
- Wet film gauges are available for use.
Cleaning
Fresh paint can be removed using water. Dried on paint may be removed using a paint scraper. Spray equipment must only be cleaned using water.
Technical Data
| Property |
Result |
| Composition |
An ultra low VOC, water-based formulation |
| Certification |
BS476 Pt 20/21 |
| ETAG 018 - up to Y exposure without topcoat (for other certification requirements, contact Technical) |
| Building Classification |
C1 and C2 environments |
| If SC804 is to be used on exterior exposed steelwork during the construction phase, it must be top coated prior to exposure, and care taken that no standing or pooling water is allowed to accumulate. For full details, please consult Nullifire Specification Guidelines |
| Properties (Typical Values) |
| Specific Gravity |
1.38 ±0.02 |
| Volume Solids |
69% ±3% |
| VOC |
0.5 g/l |
| Theoretical Coverage |
1,000 g/m² based on an applied 0.5 mm dry film thickness |
| Application Temperature |
5°C and 40°C |
| Storage |
Store in secure, dry warehouse conditions between 5°C and 35°C |
| Shelf Life |
6 months when stored as recommended in original unopened container |
Top Seal Requirements
Once DFT’s have been achieved as specified, a Nullifire top seal can be applied: TS134 (acrylic polymer), TS815 (modified acrylic) or TS816 (water-based acrylic), can be applied. Ensure the SC804 is completely dry before applying top seal.
Maintenance & Repair
Damaged areas should be abraded back to a sound surface. The surface should then be clean and dry before re-applying. FC101 Filler may be used for repairing scratches and chips. Once repaired topseal should be re-applied. Refer to Nullifire Maintenance Instructions.
Specification & Technical Service
Please contact our Technical team on 0113 2455450 (option 2) or send a message to [email protected].
Optifire+: Reliable and traceable fire protection
Optifire+ is a unique addition to Nullifire intumescent steel coatings that provides full transparency for:
- Applicators – Ability to ensure product installed on site is correct and to standards
- Main Contractors - Ability to ensure that specifications are been adhered to
- Architects and Specifiers - Ensuring your design projects comply to the latest building regulations and fire protection that is identifiable in future years
What is Optifire+ and how does it work?
Optifire+ is a unique and impossible to manipulate pigment. With Optifire+ we can be sure, at any time after the project is completed, that the product specified is the product applied – confidence that the materials submitted through the approval processes are installed to protect customer's assets.
Optifire+ is invisible to the naked eye and is added to Nullifire intumescent steel coatings. It can be identified with the traceability tool.
Why it’s important
As a product identifier, Optifire+ doesn’t change the way intumescent coatings work. But it does stimulate that they are used and are applied correctly. Nullifire intumescent steel coatings can’t be altered without it being visible and application can be checked afterwards.
With Optifire+, Nullifire goes beyond what’s expected and further endeavors to keep residents and emergency services safe, and protect the buildings that they rely on.
Optifire+ is manufactured within the UK. These locally produced products are independently tested and certified according to the highest standard in the industry.
Legal
Building owners are now more than ever been urged to act and put the safety of residents first. There’s an increased focus and scrutiny on the effectiveness of fire protection strategies in commercial and residential buildings. Negligence or simply being unable to prove that the proper precautions have been taken means risking legal action.
IMPORTANT FIRE PRODUCTS NOTICE: The information displayed on this website should be used as a guide ONLY and our Technical Department should be contacted to obtain a tailored specification and any advice necessary before you place an order for fire protection products. Fire protection products are non-returnable except in accordance with Condition 8 of the Terms and Conditions and should be applied only by an individual with the necessary expertise and experience. We will not be held liable for any resulting damage to property, human life or monetary costs incurred due to the incorrect specification you have prepared or use of fire protection products caused by your negligence, including your failure to have contacted us to obtain the relevant advice/specification.
