Our brand Nullifire is at the forefront of smart passive fire protection. We are specialists, with one focus that has not and will not change - to protect people and buildings from fire.
Nullifire intumescent coatings for structural steel, are the tried and tested way of protecting buildings and ultimately people and lives. Our intumescent coatings have been exhaustively tested both in our own laboratories but also to national and international standards in independent testing houses all over the world.
How Do the Intumescent Coatings Work?
The Basic Principle of Intumescent Coating
Fire protection of structural steel is attained by painting the steel structures with a special protective paint – an intumescent coating. The intumescent coating expands at high temperatures and forms a protective, insulating layer on the surface of the steel. Therefore, in a fire, the steel structure will be protected for a given period of time while the people are safely evacuated and the fire fighters can extinguish the blaze.
Intumescent Coating on steel structure (with steel primer underneath) – Before being exposed to extreme heat.
Intumescent Coating on steel structure – After being exposed to extreme heat.
What is a Critical Temperature?
The high temperatures reached during a building fire trigger significant changes in the structural properties of steel. Already at 300 °C, the strength of the steel begins to decrease. At 400 °C, the structural strength of the steel has been reduced by 60% of its original capability. To put these temperatures in to a context a typical building fire exceeds 1000°C.
Should the steel structure reach it critical failure temperature (typically 550-650°C), the steel would no longer be able to support the load of the building. The steels would then distort and collapse from the weight of the building. The critical temperature is the temperature at which the steel can no longer fully carry a designed load, therefore its load bearing capabilities can no longer be relied upon.
Nullifire Intumescent Coatings extend the time when, exposed to fire conditions, the steel reaches the critical temperature. This extension of time is specified typically by the usage of the building, however maybe up to 120 minutes.
Water-Based Intumescent Coatings
Nullifire pioneered water-based technology, which gives a smooth finish in a faster time than other methods. Given the environmental benefits of water-based coatings then these products are now the preferred choice among specifiers and applicators alike. For 60 minute fire protection Nullifire have now introduced SC802 intumescent coating which gives superior loadings over a wider range of section types, as well as being very easy to spray. For longer time periods up to 120 minutes our water-based SC801 product is recommend, or our high build SC902.
Our water-based systems include:
Solvent-Based Intumescent Coatings
For when environments are semi-exposed then solvent based products still provide an answer in obtaining an excellent finish in a reasonable time frame.
Our solvent-based systems include:
Our rapid-cure systems include:
- SC901 Fast Track, Off-Site Intumescent Steel Coating
- SC902 Fast Track, On-Site Intumescent Steel Coating
For primers that work in harmony with protective intumescent coatings then look no further than these recommended solutions from Nullifire. All of these have been tested to enable them to be specified together with the confidence that they will perform both in application and in the event of fire.
Top Seals are the final element, designed to make the finished steel work look good, but also to protect the intumescent basecoat underneath. Always make sure that the top seal is compatible with the basecoat by selecting from the Nullifire range.