Passive Fire Protection
Intumescent Mastic
Safire Intumescent and Acoustic Mastic is a flexible, waterbased, cartridge applied acrylic intumescent sealant.
- Flexible water based intumescent acrylic sealant
- Tested to BS476 Part 20/22
- Up to 4 hours fire resistant
- Long term flexibility
- Excellent adhesion

WHERE...
- Expansion/contraction joints, cartridge applied in gaps up to 35mm
- Irregular or uneven gaps around door casings and window sills
- Irregular or uneven gaps around service penetrations
- Sealing fire protection boards and partitioning
WHY SAFIRE...
Flexibility - Safire Intumescent and Acoustic Mastic is non-hardening, so will allow a degree of substrate movement. Resistant to cracking and splitting.
Excellent Adhesion - Safire Mastic is is formulated to give excellent adhesion to most building substrates including brick, concrete, steel and plaster without the use of costly primers.
Water Based - Safire Mastic is virtually odourless, and tools and equipment are easily cleaned without the use of solvents.
Environmentally Friendly - Safire Mastic is Halogen free and contains no fibres, so can be used with confidence.
Smooth Finish - Safire Mastic can be easily tooled to a smooth finish using a wet spatular if required.
INSTALLATION...
Safire Mastic is extruded from a cartridge loaded into a standard skeleton cartridge gun.
- Ensure all surfaces are sound, clean, dry and free from dust or grease.
- Use the appropriate backing material to set the depth of the seal. Joint width or depth should be not less than 6mm so that there is sufficient material to give the movement required.
- Gun in the sealant, taking care to avoid entrapping air or leaving gaps, and ensure there is a complete contact between sealant and substrate.
- Tool down using a wetted spatular. Store in cool dry conditions.
SPECIFICATION COMPLIANCE
- International 4hrs tested to ISO834
- UK 4hrs tested to BS476 pt22
- Netherlands 4hrs tested to NEN3884/nen6069
- Belgium 4hrs tested to NBN713.020
- France 6hrs tested to CSTB91.3222
- Germany 4hrs tested to DIN4102 part 1 (PA-111 2.2.2022)
- USA 2hrs tested to ASTME 119
TECHNICAL SPECIFICATION
PHYSICAL FORM
Thixotropic paste
COLOUR
White, other colours available to special order
WORKING TIME
25 minutes
SKINOVER TIME
20 minutes
CURE RATE
3mm per day
MOVEMENT
+/- 10%
APPLICATION TEMPS LIMITS
0ºC to 70ºC
SLUMP
Nil under 30mm joints
SURFACE TEMPS LIMITS
0ºC to 100ºC
PACKAGING
310ml cartridge, 25 per box
SHELF LIFE
9 months if stored at 5ºC to 30ºC