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Determining Fire Doorset Resistance

When it comes to fire doorset resistance, it is expressed in terms of time. The doorset is exposed to a ‘standard’ fully developed fire in a test furnace until failure occurs, according to a certain criterion.

This performance testing is to evaluate integrity and insulation in accordance with either BS 476 or BS EN 1634.

Typically, a fire-rated doorset should:

-Be capable of meeting the performance in accordance with its specification or design.

-Be assessed from test evidence against appropriate standards, as meeting that performance.

Read on to find out more…

Why Whole Door Assembly Testing is Crucial When Measuring Resistance of a Fire Doorset

A fire doorset should be tested for fire doorset resistance by an independent body and must be carried out on an entire doorset, rather than just individual components.


Because the test is meant to assess how an actual fire doorset combination performs under fire conditions and not just a single door component.

In other words, the door leaf must be tested alongside the other elements that make up the whole doorset – such as the door frame, the hardware and the intumescent protection. Take a look at last week’s blog to find out the essentials of a fire doorset.

Fire Door guide CTA

What About Small Changes in Detail?

Any change, however small, may still impact the performance of fire doorsets, which may lead to catastrophic consequences.

For example, when a fire doorset is manufactured, the intumescent recipe has also been manufactured to the doorset’ s unique specification. Using incorrect intumescent materials will almost always invalidate certification.

We understand that, as a specifier, there’s a need (and even pressure) to make cost-savings wherever possible, so it’s likely that you’ve considered purchasing component parts. But when it comes to fire doorset specification, you simply can’t take that gamble. Take a look at the following blog posts to find out more:

The Impact Of Value Engineering In Fire Doorset Specification

Fire Doorset Procurement: An Argument for Buying Component Parts

What Does The Fire Doorsets Test Procedure Look Like?

The test centre simulates a real, on-site scenario whereby the entire doorset is fixed in a wall.

Sensors are attached to the face of the door and the duration of the test is the number of minutes for which the doorset is to be classified. The doors will receive a rating, such as:

-FD30 – 30 minutes

-FD60 – 60 minutes

-FD90 – 90 minutes

-FD120 – 120 minutes

Door manufacturers are often challenged over whether fire doors should be tested from both sides.

The convention to test timber doorsets in one exposure direction with the door leaf, or leaves for double doors, opening into the test furnace has long been established as a practical rule. This is supported by Standards BS 476:1987 (Parts 22 and 20) and BS EN 1634-1:2014

During testing, the doorset is observed for stability and integrity and a combustible fibrous pad is placed on the unexposed side of the door to see when it ignites.

Here’s a video of a fire doorset being tested:

Conclusion: Consider Third-Party Certification for the fire doorset resistance

Third-party certification is highly recommended. It verifies the doorset’s design, performance, manufacturing process and quality assurance.

BM Trada’s Q-Mark fire door manufacture scheme, for example, was established to provide reassurance to purchasers and specifiers that products meet regulations and are manufactured to consistent quality. Other schemes include BWF-Certifire.

Such doorsets will be marked with the appropriate certification badge.

If you have an upcoming project and are in need of a bespoke, certified, fire-rated doorset, get in touch with an expert today.

Fire Door guide CTA 





Trusted and Accredited Manufacturers

  • CHAS Accredited Contractor
  • BM Trada Q Mark Certification
  • Constructionline Gold Member 2018
  • BWF Membership Certificate 2020

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