Fire Resistance Testing: Are Manufacturers Maximising the Value of Their Evidence?
Fire resistance testing represents a significant investment for doorset manufacturers. However, the commercial value of a successful test extends beyond the performance of the individual specimen.
By considering the direct and extended application of test results during product development, manufacturers can establish the evidence required to support a wider range of product configurations, potentially reducing additional testing costs and improving their ability to respond to customer requirements.
Understanding The Limitations of a Fire Resistance Test
BS EN 1634-1 specifies the method for determining the fire resistance of door and shutter assemblies and openable windows.
The test establishes the performance of a particular assembly under standard test conditions. For doorsets, this includes the interaction between the door leaf, frame, glazing, hardware, seals, supporting construction (the wall) and installation details.
Changes to these components can influence fire resistance performance. For example, increasing door leaf dimensions, modifying glazing arrangements or substituting hardware may affect the behaviour of the assembly during a fire.
Consequently, a successful test does not automatically establish equivalent performance across every configuration within a manufacturer's product range.
The extent to which test results can be applied to alternative configurations is determined through the applicable classification and field of application rules.
Direct Field of Application
BS EN 1634-1 includes a direct field of application that defines permitted variations to a tested construction, subject to specified conditions.
The application of these provisions requires competent technical evaluation of the test evidence and the relevant classification requirements.
This is documented through a classification report prepared in accordance with BS EN 13501-2. The report establishes the applicable fire resistance classification and identifies the field of application, including permitted variations from what was tested.
Where variations are supported by the direct field of application, they can be included within the classification without additional testing, provided all relevant conditions are satisfied.
However, these provisions are specific. They do not permit unrestricted changes to dimensions, materials, components or installation arrangements.
Manufacturers should therefore ensure that proposed product configurations fall within the documented field of application before making fire resistance performance claims.
Extended Field of Application
Where a proposed variation falls outside the direct field of application, extended application (EXAP) may provide a means of establishing a wider field of application using existing and, where necessary, additional fire resistance test evidence.
BS EN 15269-1 establishes the general requirements for extended application of test results for doorsets, shutters and openable window assemblies. The other parts of the BS EN 15269 series provide specific rules for different product types and constructions.
For hinged and pivoted timber doorsets, BS EN 15269-3:2022 provides rules for extending the application of fire resistance test results obtained in accordance with EN 1634-1.
Annex A of BS EN 15269-3:2022 defines the construction parameter variations that may be considered. These are organised into six sections:
Section A – Door leaf (Table A.2): Variations relating to the door leaf, including dimensions, construction, materials, seals and finishes.
Section B – Door frame (Table A.3): Variations relating to door frame construction and its constituent materials and dimensions.
Section C – Items of building hardware (Table A.4): Variations involving hinges, locks, latches, closing devices and other building hardware.
Section D – Side, transom and over panels (Table A.5): Variations involving the configuration and construction of associated panels.
Section E – Glazing (Table A.6): Variations involving glazing and its associated construction details.
Section F – Supporting construction and attachment of door frame or side/over panels (Table A.7): Variations involving supporting constructions and attachment arrangements.
Each construction parameter variation is subject to specific rules that determine whether an extension is possible using the available evidence or whether additional testing is required.
The process requires evaluation by a person competent in fire resistance testing and extended application, in accordance with BS EN 15269-1 and the relevant product-specific part of the series.
Not every variation will be permissible, and additional testing may be necessary.
An extended application report is prepared in accordance with BS EN 15725 and the requirements of BS EN 15269-1. The results are then used to prepare a classification report in accordance with BS EN 13501-2, establishing the supported fire resistance classification and field of application.
The Commercial Importance of Test Programme Design
The potential benefits of extended application are greatest when manufacturers consider their intended product range before commissioning testing.
A test programme developed around a single configuration may provide limited support for subsequent product variations. Where those variations fall outside the available field of application, further testing or technical evaluation may be required.
Conversely, identifying the intended range of sizes, glazing arrangements, hardware and supporting constructions at the outset allows the testing strategy to be developed around those requirements.
This can help manufacturers:
Reduce unnecessary testing: Identify where existing evidence and applicable extended application rules can support proposed configurations.
Improve market responsiveness: Establish supported product variations before they are requested by customers.
Support product development: Identify the technical limitations that may influence future design decisions.
Control compliance risks: Ensure declared fire resistance performance is supported by evidence applicable to the product supplied.
Provide investment clarity: Establish a defined testing roadmap, allowing business leaders to understand the intended product range, anticipated expenditure and expected commercial outcomes before committing to the programme.
· Improve return on investment: Direct expenditure towards commercially important product configurations rather than commissioning individual tests and only subsequently establishing their potential extended application.
This approach also provides a basis for measuring the outcome of the programme against its original objectives. Once testing and classification are complete, manufacturers can establish which planned configurations are supported, identify any outstanding evidence requirements and assess the commercial value delivered by their investment.
Maintaining Control of the Supported Product Range
Developing appropriate evidence is only one part of demonstrating product performance. Equally important is ensuring that the evidence can be understood and applied consistently across the business.
A clearly structured suite of extended application and classification reports should define the supported product configurations, permissible construction parameter variations and any applicable restrictions in a manner that is accessible to product development, sales, manufacturing and technical compliance teams.
This makes it easier for commercial teams to identify and sell configurations supported by appropriate evidence, while making it more difficult for unsupported variations to be offered or manufactured without further technical review.
The reports can also form the basis for product specifications, configuration controls and approval processes that prevent unauthorised substitutions or modifications.
For business owners and shareholders, this provides an important additional benefit. By reducing ambiguity and strengthening control over the products being supplied, manufacturers can better manage their exposure to compliance failures, contractual disputes, remedial costs and reputational damage.
Ultimately, well-defined and accessible technical evidence helps manufacturers maintain control over their product offering and reduces the risk of products being placed on the market with fire resistance claims that the available evidence does not support.
Making Testing Investment Work Harder
Fire resistance testing should be considered as part of a manufacturer's wider product development and evidence strategy.
A successful test establishes valuable performance information. Competent evaluation, classification and the application of direct or extended application rules determine how that evidence can support other product configurations.
Considering these requirements early can help manufacturers make more informed decisions about testing expenditure, product development and market opportunities.
At UKTC, our Technical Services team support manufacturers in developing test programmes and evaluating the field of application of their fire resistance evidence.
By establishing the intended product range and evidence requirements at the outset, manufacturers can make better use of their testing investment while maintaining confidence in the performance claims associated with their products.
Developing a new doorset range or reviewing existing fire resistance evidence?
Contact UKTC to discuss your testing, classification and extended application requirements.
About the Author
Andrew Hutchison, Operations Director
Andrew Hutchison is Operations Director at UKTC, bringing extensive experience in fire testing, product certification and regulatory compliance. Holding a Master’s degree in Engineering from the University of Glasgow, Andrew has played a key role in developing UKTC’s testing capabilities and achieving UKAS accreditation.
With a strong focus on improving industry standards, Andrew shares his technical knowledge and insights to help manufacturers navigate evolving regulations, demonstrate product performance and contribute to a safer built environment.
