Designing better fire protection

As a trade association, the Association for Specialist Fire Protection (ASFP) has had a long-term policy to work towards third party certification for passive fire protection systems. At the moment our members have this certification on a voluntary basis for products made by manufacturer members, and for the works carried out by contractor members it is a mandatory condition of membership.

These third-party schemes bring forward many different benefits for the ultimate end client, building owners and occupiers. We continue to work with UK government and in other countries to urge for such requirements to be made mandatory.

Third party certification of products ensures that the product testing is clearly presented and well understood, and that the product quality is maintained throughout time, so that the performance of the product leaving the factory gate today is identical to that when that product was initially certificated.

Meanwhile, installer third party certification schemes demonstrate that the installers of passive fire protection carry out their roles in repeatable recorded ways, guaranteeing that they offer the best chance of the project being successfully completed, with the right products being installed correctly.

But what about the obvious gaps in the construction process?

There remains a number of areas of concern related to the specification and design of passive fire protection schemes. This has become a topic of increasing significance as all parties in the supply chain pay more heed to where design liability rests in a post-Grenfell world. However, rather than working towards better design, all too often we see parties working to ensure that their share of any design risk is reduced or even eliminated.

Common specification questions

In my role as ASFP’s Technical Officer, I receive several calls and emails every week from architects and specifiers asking for clarification. There are a few topics that crop up again and again. The ASFP has produced a number of Technical Guidance Documents and Advisory Notes that cover some of the topics mentioned below. They can be downloaded from the ASFP’s website at www.asfp.org.uk.

I am amazed that, even though ASFP has published guidance against the use of single pack polyurethane foams as a way of firestopping, I still get to hear of tales where these foams are incorrectly specified and used. Not all of these foams have fire testing and certification. However, those that do, only tend to have testing and certification to BS EN1366-4, the linear gap test method.

If a can mentions testing for up to 4 hours of fire resistance to BS EN1366-4, this covers linear gaps between walls (likely blockwork, or maybe flexible walls) but not any penetration with a pipe or a cable coming through. Pipe and cable penetrations are tested to BS EN 1366-3. If a foam is wrongly used in this type of application, it will fail for fire integrity within 10 minutes. The ASFP video The correct specification and installation of fire-stopping, clearly demonstrates this in a fire test showing a range of pipe and cable penetrations.

In the area of Reactive Coatings (intumescent coatings), for structural steel, ASFP has published Advisory Note 12, a best practice guide on the specification of intumescent coatings. The guide includes a checklist for specifiers to help avoid some of the common misconceptions.

The ASFP has several active Technical Task Groups, which are all working towards producing new and improved guidance to address the above issues and many of the others that come across our desks regularly. Keep watching the ASFP website for details of any new guidance.

Design and build

The current practice of design and build often gives rise to some of the worst examples of passive fire protection installation because the installations are not designed properly in advance and the fire-stopping contractor has to design something ‘on the hoof’.

Under design and build schemes, a client will offer the basic concept, or a brief, to construction companies who will undertake (with their own design team) to deliver the completed building largely to performance-based requirements. The design and construction becomes the contractor’s responsibility and he will deliver a building to meet the client’s needs.

This often means that the first time a fire-stopping detail is considered is after all the services have been installed, giving the fire-stopping contractor a headache, as they are often confronted with arrangements for which there are no tested and/or certified solutions.

The main challenges here often involve firestops where pipes, cables and ducts/dampers occur in the same penetration. At the moment there are no approvals for these combined penetrations, and pipes and cables should be kept separate from ducts/dampers.

Dampers also often give the fire-stopping contractor a major issue on design and build style contracts, since they are often installed in the wrong place; either not on the proposed compartment line, or not where the compartment line ends up being constructed!

The best solution

In reading all the above, you are probably thinking that it needs many clever people to deal with all these questions; and you would probably be correct. However, the wisest solution is actually to avoid the problems altogether. Considering the design and specification of passive fire protection early in the design process of a building can help avoid many of the pitfalls before they occur.

The ASFP has been working with the Royal Institute of British Architects (RIBA) on creating a Fire Safety Overlay for the RIBA Plan of Works. This provides a detailed specification for fire protection at the design stage and a schedule for fire throughout the construction process. It includes sign offs as construction progresses, with all information reaching the end-user to support adequate fire risk management.

The ASFP is working to increase the quality of installed fire protection within all buildings. While continuing to push for mandatory third party certification of products and installers, we will promote early planning of passive fire protection as best practice and campaign for an end to the design and build culture in construction.