As the construction industry advances, its methods change as well. However, fire test standards often lag behind, creating difficulties for stakeholders when it comes to applying tested details to modern applications.
This article explores examples of gaps between testing and reality, and highlights the importance of early engagement and collaboration in achieving ultimate building compliance.
Why Fire Test Standards Are Struggling to Keep Pace
Let’s take a look at some examples
Many fire test standards haven't been updated in a while, and recent updates still miss key areas.
Service penetrations, for example, are tested in accordance with the fire-resistance test standard BS EN 1366-3. At the end of 2021, this test standard was updated, greatly improving on the previous 2009 version; however, even with this update, the standard is still far behind the realities of construction and what is actually being built on-site today.
When it comes to wall or floor types that service penetrations are tested to, the standard focuses heavily on double-skin flexible plasterboard walls, with only a small section on single-skin plasterboard walls, which are proving increasingly popular in modern construction.
Other wall types used in many construction projects, such as cross-laminated timber (CLT), sandwich panels, and shaft walls, have little to no guidance in the test standards at present.
Similarly, for floor construction, the standard covers solid concrete floors, whereas sites are now using profile deck floors, hollow core slabs, and timber floors, like plasterboard ceilings.
Another key example where standards are struggling to keep pace is the use of partial penetrations – areas where services penetrate only one side of the wall or the supporting construction and do not extend completely through, such as radiator pipes.
There is currently no test standard for these types of penetrations, even though they are used frequently on-site. A draft standard, BS EN 1366-14, has been under development for many years, and there is currently no timeline for its release.
So, you might be curious about the delay in updating or creating test standards.
A big factor is that many European countries need to participate and agree on the test standard, which naturally takes time to ensure everyone is aligned, especially since not all countries design and build in the same way.
That’s why early engagement in a building’s passive fire protection design is crucial to guarantee that what you’re planning to build is fully covered and supported by relevant test standards and evidence.
Understanding the Rules of Evidence Transfer – Flexible Walls v Rigid Walls
When it comes to fire testing, despite the challenges with the standards, there are also positives, such as the inclusion of agreed-upon methods that naturally cover other applications within the field of application, meaning not all specific scenarios will need to be physically fire tested.
However, for a field of application to be allowed when the evidence is formally classified or assessed, manufacturers must conduct fire tests on the products or applications against the designated 'worst-case’ scenarios.
For example, testing the fire resistance of service penetration seals through flexible walls, such as plasterboard, is considered more challenging than testing through rigid blockwork walls because flexible walls tend to deflect and move during a fire test, whereas rigid walls do not. Additionally, flexible walls generally cannot withstand fire as long as rigid walls.
Therefore, the test report is sent to an accreditation body to obtain a designated field of application – known as the classification report.
When this flexible wall test data is submitted to an accreditation body for a classification report, the evidence will be extended to include rigid walls that meet criteria such as minimum thickness and density.
Furthermore, because it is impractical to fire test every variation, the interchangeability section, agreed upon by all countries, sets out general rules to follow. For instance, when tested in a specific way, double-skin flexible walls cover not only the wall type they’re tested on but also thicker walls and insulated/uninsulated walls.
This highlights the importance of requesting the correct documentation for passive fire protection, which includes a classification report or a field-of-application assessment.
Other documents you may be provided with, such as ETAs (European Technical Assessments), typically bring together various reports under one banner, including fire resistance performance and acoustic data.
The field of application for fire resistance, as presented in documents such as an ETA, will still come from the initial classification report.
The key is to obtain the correct document that provides the ‘overall designated field-of-application information’ to ensure it covers your scenario.
Where Projects Typically Go Wrong
Passive fire protection can be complex and requires early collaboration with many different parties to ensure the correct products are specified, designed, and installed. 
Projects typically go wrong when the necessary information to create a compliant and buildable passive fire protection design is not understood.
Just for service penetrations alone, there are many factors to consider, such as the types of service, the materials of the floors and walls, and the required fire ratings.
It is common for projects with a 30-minute fire rating to simply opt for one of the many fire-tested single-skin walls on the market; however, because such walls are likely to have penetrations, reestablishing their fire resistance depends heavily on several factors.
It is crucial to consider what will pass through, as not all applications may have been fire tested and your overall design is only going to be as good as your weakest part.
Construction is a team effort that requires input from all those involved to achieve ultimate building compliance. Everyone, from the MEP to the Architect, has an impact on passive fire protection in some form.
Teams can’t work in silos; early engagement at the right stage of design is the only way to ensure plans are practical and achievable for everyone.
Closing the Gaps with Technical Assessments
Correct technical assessments are a fundamental part of construction and will likely always be required for many reasons, some of which stem from test standards not being up to date with all scenarios and applications.
When we discuss technical assessments, we mean official documents prepared by qualified, impartial, and competent third parties, typically in accordance with the PFPF Guidelines. They’ll use agreed-upon methods, scientific knowledge, and sufficient primary fire test evidence.
The PFPF Guidelines provide a framework for this by setting out a clear structure for assessing an individual's competency and for carrying out assessments responsibly.
Technical assessments are particularly useful when no relevant test standard scope exists for systems such as sandwich panel wall systems, or when interactions occur between different test standards, for example, steel beams penetrating a compartmentation wall line.
Without technical assessments, the construction industry risks grinding to a halt as modern forms emerge – still, such assessments must be used correctly and only when required.
While the industry cannot control the gap between evolving construction methods and fire test standards, it can choose to prioritise early engagement and collaboration in building design prior to building.
These steps will help ensure that building designs are based on available tested solutions, eliminating grey areas and ensuring that what works in theory also works on site: protecting people and property.
