Intumescent fire resistive coatings are applied to steel building supports such as beams, channels, pipes and tubular columns to protect their structural integrity in fires. Alpha Fire Protection use calibrated, non-destructive elcometer gauges that are ideal for measuring the dry film thickness of these coatings and for ensuring that they are applied under the correct conditions.
Although steel does not burn, it can be severely weakened when exposed to high temperatures for extended periods, such as in a building fire.
When exposed to fire, an intumescent coating generally expands in thickness by 15 to 30 times in a standard test, forming a thick layer of foam that protects the steel by thermally insulating it from the heat. Some manufacturers report expansions as great as 100 times for unspecified conditions. As part of the expansion process, most coatings generate an outer ash-like char layer. As the fire continues, the ash coating erodes, exposing the remaining intumescent coating to form more char. Depending on the coating thickness, this process repeats itself several times.
Intumescent fire resistive coatings generally require a primer for adherence. A decorative/protective topcoat may also be necessary – especially in humid environments. A reinforcing mesh can be used to better retain the char layer on certain shapes.
Alpha Fire Protection have extensive experience in carrying out DFT testing using the correct equipment and procedures to ensure an accurate and high quality service. We are based in Dublin but provide nationwide coverage.