Nullifire Advice with Integrity – Clusters of pipes

Patrícia Gabriel / 15 January 2024

Is it possible to test the below configuration of pipes to EN1366-3?

In just a few words, the answer is YES!

The EN1366-3 standard does not consider the release of smoke or hot gases. So, while the seal can pass the relevant test with ease, there will be a period of time that smoke and hot gases can pass through the area shown which cannot be sealed.

For combustible pipes, the closer device should be around each individual pipe and as a result, this will close the gap left after the combustible pipe has melted. This will allow the closure device to expand and fill all voids.

With non-combustible pipes, the release of hot smoke and gases is unavoidable and will be continuous for the duration of the fire test. There will be no failure recorded in the test as no gap gauge is possible, and fire cannot seek a pathway along the non-combustible element.

If you understand the regulations and requirements for compliance, you will insist on being permitted to create a smoke seal when fire stopping, ensuring, of course, that it has also passed the relevant test to EN1366-3, sometimes this does unfortunately result in the pipes being required to be relocated. Naturally, if the pipes are fitted individually as they are fire sealed (Retro Fit), the potential issue is resolved. If a fire is tested as a retrofit system, and all is correctly sealed, that is the only condition the tested data is relevant.

Knowledge is a Nullifire essential,

Knowledge leads to compliance,

Always look beyond the obvious.

For further details on tested service Integrity and Insulation requirements or results. Please contact our Technical team via or on 01942 251 400. They will always give you Answers with Integrity.