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Nullifire FS702 Intumastic Fire Resistant Acrylic Sealant

A water-based acrylic sealant which cures to give a firm but flexible fire seal.

  • Provides up to 4 hours fire resistance
  • Suitable for flexible walls and rigid walls and floors
  • Flexible formulation withstands up to 30% movement
  • Excellent acoustic and air seal
  • Optifire and Optiire+ unique traceability
  • Used for sealing FB750 Intubatt
Delivery options
Next day delivery slots available upon request. Call us on 01483 418418 for details.
Frequently bought together

Total price

£28.15 (Ex VAT)

This item: Nullifire FS702 Intumastic Acrylic Sealant 600ml £2.95 (Ex VAT)



Nullifire FS702 Intumastic Fire Resistant Acrylic Sealant is a water-based acrylic sealant which cures to a firm but flexible fire seal. Suitable for use in various construction joints offering up to 30% movement within the joint whilst providing an excellent acoustic and air seal.

Our excellent formulation also incorporates a unique identification property offering architects, specifiers, main contractors, and applicators guaranteed traceability of product on-site. Optifire technology is activated by exposing the product's surface to a UV light source, which offers easy and instant product identification. Nullifire FS702 Intumastic also features Optifire+ visible with a Nullifire detector offering lifetime identification, even after a fire. 

Recommended areas of use

  • Static and movement linear joints (masonry, flexible wall to masonry, rigid walls or floors and flexible floors)
  • Window and door joints (masonry to timber/steel)
  • Use with FB750 to flexible or rigid walls or rigid floors
  • Cold smoke seal
  • Service penetration sealing: copper and steel pipes, cable bundles or trays and ladders (with and without FL025 Intuflex Insulation Wrap)
  • Suitable for service movement joints – please contact our technical advisors for additional guidance.


  • Up to 4 hours fire resistance – tested to EN 1366-4. EN 1366-3 And bs 476 Pt 20-22
  • Withstands up to 30% movement capability (during fire test)
  • Ideal for sealing FB750
  • Optifire and Optifire+ unique traceability identifiers
  • Excellent acoustic (up to 55dB) and air seal (up to 2,000 Pa)


Properties 600ml


Surface preparation:

All surfaces must be clean and sound, free from dirt, grease, and any other contamination. Wood plaster and brick may be damp but not running wet.

Porous or high gloss surfaces: must be primed before application

If a clean line is required on adjoining substrates, masking tape should be used. Please check the specification is suitable for movement, fire rating and gap size required.


  • Insert required backing material (refer to performance on backing materials), oversized to joint width to ensure stability, to provide correct depth of seal.
  • A light water spray will aid adhesion if a rock mineral fibre backer has been applied.
  • Using a sharp knife, cut the nozzle of the cartridge to bead size and angle required.
  • Gun sealant into gap to required depth by applying an even pressure to the trigger.
  • Work and tool to a smooth finish immediately with a wet profiling tool or spatula.


Safety Data Sheets are provided, please read for pre-application guidance and relevant application detail prior to application. 
Use in well ventilated conditions and ensure all recommended protective equipment is worn during handling and use of this product. For full recommendation, refer to the Safety Data Sheet. 

Important information:

  • Do not use around CPVC pipes – for this specific application, please use FS719 HP Blue.
  • If used around Pegler X-Press Carbon Steel Pipes, the pipe manufacturer should be consulted, and their recommendations followed.
Test results

Test results

Extensive testing is what makes us the most highly qualified paint and repair manufacturer on the market. Our tests cover just about everything you might want to know about a product.

Key tests for Nullifire FS702 Intumastic Fire Resistant Acrylic Sealant:

  • Acoustic rating: Up to 55 dB when tested to BS EN ISO 10140:2-2010
  • Air permeability: Airtight up to 2,000 Pa when tested to BS EN ISO 1023:2

Full test results can be found on the Technical Data Sheet. 

Data sheets

Data sheets

Safety data sheets

Safety Data Sheet

Technical data sheets

Technical Data Sheet

Declaration of performance

Nullifire - FS702
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£2.95 (Ex VAT)

In stock

Delivery options
Next day delivery slots available upon request. Call us on 01483 418418 for details.

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Nullifire FS702 Intumastic Fire Resistant Acrylic Sealant

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