Fire performance is a key consideration when specifying flooring and access systems in industrial and commercial environments. GRP grating is fire resistant, but it’s important to understand exactly what that means, how it’s tested, and how standards such as BS476 apply.
This guide explains how GRP grating performs in a fire and what BS476 compliance actually tells you.
Is GRP Grating Fire Resistant?
GRP grating is manufactured using fire-retardant resin systems, which significantly reduce flame spread and heat release compared to untreated plastics. While GRP is not completely fireproof, it is designed to resist ignition and limit the spread of flame.
In most industrial and access applications, GRP grating offers a safe and compliant solution when the correct resin system is specified.
What Does BS476 Mean?
BS476 is a British Standard that assesses the reaction of materials to fire, rather than their structural performance during a fire.
For GRP grating, the most relevant section is:
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BS476 Part 7 – Surface Spread of Flame
This test measures how quickly flame spreads across the surface of a material.
BS476 Part 7 – Class 1 Explained
GRP grating manufactured with fire-retardant resins commonly achieves Class 1 to BS476 Part 7, which means:
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Very limited flame spread
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Reduced contribution to fire growth
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Suitable for use in many industrial and commercial environments
A Class 1 rating is often specified for walkways, platforms, stairs and access routes where fire performance is required but full fireproof construction is not necessary.
How Fire Resistance Is Achieved in GRP Grating
Fire resistance in GRP grating is achieved through the resin system used during manufacture.
Most industrial GRP grating uses:
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ISO or isophthalic polyester resins
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Integrated fire-retardant additives
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A surface veil to improve durability and flame performance
These components work together to slow ignition, reduce flame spread and minimise smoke generation.
GRP Grating vs Steel in a Fire
Steel does not burn, but it loses strength rapidly at high temperatures, which can lead to structural failure during a fire.
GRP grating:
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Does not conduct heat as quickly
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Maintains integrity longer in lower-temperature fire scenarios
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Produces less radiant heat
For pedestrian access systems, GRP grating often provides a more predictable performance in early-stage fire conditions.
Where Fire-Retardant GRP Grating Is Commonly Used
Fire-rated GRP grating is widely used in:
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Industrial walkways and platforms
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Water treatment facilities
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Manufacturing plants
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Chemical and processing environments
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External access routes
It is particularly suitable where slip resistance, corrosion resistance and fire performance are all required.
What GRP Grating Is Not Suitable For
GRP grating may not be suitable where:
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Very high fire resistance periods are required
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Extreme temperatures are expected
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Fire performance must meet structural fire resistance standards rather than surface spread tests
In these cases, alternative materials or additional fire protection measures may be required.
Choosing the Right GRP Grating
When fire performance is important, always confirm:
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The resin system used
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Compliance with BS476 Part 7
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The required class rating
Selecting the correct specification ensures compliance, safety and long-term performance.
