How one product can hold several different classifications
Your product has a classification of B-s1,d0. Would it still achieve that same classification when it's installed on site?
Most people read a classification report the same way. Find the class, check it matches the specification, and move on. That's not the full picture, a classification only tells part of the story. Until you know how the product was tested, it may not reflect how the product is actually being used on site and that could mean a very different performance in the event of a fire. A classification has to be used alongside the field of application to identify how a product has been tested and how it can be installed and used on site.
What is the Field of Application?
This section of a classification report sets out exactly what your classification covers: the substrate the product was fixed to, how it was fixed, whether there was a cavity behind it, where the joints sit, and which adhesive was used, and how much.
Fire tests are carried out on products as they're intended to be installed, not as they're sold. A lining fixed tight to masonry can behave very differently to the same lining on battens with a ventilated cavity behind it.
That's why one product can hold several classifications. For example, a product with the classification of B-s1,d0 fixed directly to a non-combustible substrate may only achieve C-s2,d0 over a cavity. Same product, same factory, same day - a different result, because the installation has changed.
When the evidence stops applying
Nothing about the product itself has to change for a classification to change - the installation can change instead. If someone value-engineers the backing board or swaps in a different adhesive, the product on site can look identical to the one that was tested, while the evidence no longer covers it.
Five questions worth asking about every classification report you rely on:
What substrate was it tested on, and is that what your customers actually build on?
Was there a cavity in the test? Is there one on site?
Does the report name a specific adhesive, or a generic type?
What thickness range does it cover, and are you selling outside it?
If the product can be fitted either way round, were both faces tested?
Scrutiny of fire test evidence has moved a long way in recent years. A classification that doesn't match the installation isn't a technicality - it's a gap in the evidence chain.
Not sure your classification still matches how your product is used? Contact our Reaction to Fire Test Experts.
United Kingdom Testing & Certification, A SOCOTEC company, are a UKAS accredited laboratory for reaction to fire and fire resistance testing. Its reaction to fire test suite allows manufacturers to test and prove performance with a BS EN 13501-1 classification. On average, the UKTC team issue test and classification reports within two weeks of the test.
