Passive Fire Protection: Systems, Ratings and Tests

A wall is only as good as the last hole somebody drilled in it. On paper it holds fire for two hours. On site, a cable tray went through it on a Friday. The gap got filled with whatever was in the van. Nobody wrote it down. That gap is where the plan stops and the guessing starts. This guide is for the people who buy the product, not the people who fit it.

We supply fire protection products to contractors, distributors and developers across Africa, Europe and the United States. Reading certificates is most of our day. This page shows you how to read one properly, and the one thing that decides whether a seal will do what the drawing promised. The range behind this sits on our passive fire protection product pages.

What passive fire protection actually means

The word passive is doing real work. Nothing detects, nothing triggers, nothing needs power or water. The performance is built into the material and the way it was assembled, and it sits there for the life of the building doing nothing at all until the day it matters. That is its strength and its weakness in one. A sprinkler head painted over will usually be spotted. A missing collar behind a plasterboard patch will not, because there is nothing to inspect unless somebody opens it up. Under Regulation (EU) No 305/2011, the Construction Products Regulation, safety in case of fire is one of the basic requirements construction works must satisfy, covering both the stability of the structure during a fire and the limitation of fire spread. Every product family below exists to serve one of those two aims.

Active vs passive fire protection, and why a building needs both

The honest way to think about it is timing. Active measures buy the first minutes by raising the alarm and slowing growth. Built-in protection buys the hour after that, by keeping the fire in one compartment while people walk out and the fire service walks in. The two are designed together, which is why substituting one for the other mid-project is a design decision and not a purchasing one. BS 7974:2019, the code of practice for applying fire safety engineering principles to the design of buildings, sets out the framework used when a project is designed on performance rather than on prescriptive guidance, and it covers new buildings and existing ones. If a project follows that route, the balance between detection, suppression and compartment integrity has already been calculated. Changing one side of it on site changes the answer.

Compartmentation is the idea everything else serves

In England, Approved Document B is the statutory guidance covering fire safety matters within and around buildings, published in two volumes, one for dwellings and one for buildings other than dwellings, in a 2019 edition carrying later amendments. It is the document that tells a designer how many minutes a given boundary needs to hold. Comparable guidance exists in Ireland, Germany and the Netherlands, and African markets often draw on British or European practice with local amendments, so we treat the destination country as part of a requirement rather than an afterthought. You can see the countries we ship into on our markets page. The number on the drawing is only half the instruction. The other half is which test regime that number was written under, and those two halves must travel together.

Passive fire protection products, and the test each family answers to

The families overlap less than a catalogue makes them look. A sealant that performs beautifully around a copper pipe has no answer for a 110 mm plastic waste stack, because the failure mode is different: the plastic disappears and leaves a chimney, so the product has to expand fast enough to fill the void the pipe used to occupy. A board rated for a riser shaft is likewise not automatically a substrate for anything else. Our SIMFY FIRESYS division handles these as separate technical categories rather than one shelf, because the evidence behind each differs and so do the questions a specifier asks. The table below is the short version we use when a requirement arrives with no product name attached.

How performance is proved

BS EN 1363-1:2020 establishes the general principles for determining the fire resistance of elements of construction under standard fire exposure, and it defines the common procedures, including the temperature and time curve, that the individual test methods sit on top of. The specific method then applies: BS EN 1366-3:2009 covers penetration seals, EN 1366-4 covers linear joint seals, EN 1366-1 covers ventilation ducts, and EN 1634-1 covers door and shutter assemblies. After the furnace, BS EN 13501-2:2016 provides the procedure for classifying construction products and building elements using data from those tests. That classification standard is where E, I and EI come from. E is integrity, meaning flame and hot gas do not pass. I is insulation, meaning the unexposed face stays cool enough not to ignite what is touching it. EI 120 means both, for 120 minutes, in the arrangement that was tested.

Reaction to fire is a separate question with its own document. BS EN 13501-1:2018 classifies construction products using data from reaction to fire tests, describing how much a material itself contributes to a fire rather than how long an assembly holds one back. A board can be strong on one measure and irrelevant on the other, and buyers routinely quote one when the specification asked for the other.

The part most pages leave out: the rating belongs to a system

This is the single most consequential thing a buyer can understand, and it is the thing catalogues are quietest about. ASTM E814 is titled Standard Test Method for Fire Tests of Penetration Firestop Systems. The word in the title is systems. UL 1479, Fire Tests of Penetration Firestops, evaluates firestops used in openings within fire-resistive wall, floor and floor-ceiling assemblies, and assigns an F rating for the time before flame appears on the unexposed surface, a T rating that adds a temperature rise criterion, an L rating for air leakage, and a W rating for resistance to water passage. Read those descriptions closely and the same logic appears: what is being rated is an opening in a defined assembly with a defined thing going through it, not a tube of mastic.

So a certificate reading EI 120 is shorthand for something much longer. It means a seal of this product, at this depth, in a dense blockwork wall of a stated thickness, around a plastic pipe of a stated diameter, in an aperture of a stated size, achieved integrity and insulation for 120 minutes. Fit the same product around a steel pipe, or in a plasterboard partition, or in a bigger hole, and the certificate describes a test that was never run. Nothing on site looks different. The paperwork simply stops matching reality, and stays that way until an inspection or a fire finds it.

Two consequences follow. A substitution is a technical change, not a commercial one, and needs evidence of its own. And the field of application matters as much as the rating: a serious report states the range of substrates, aperture sizes and service diameters the result may be applied to. Passive fire protection systems are classified as assemblies, never as tubes and boxes. So we ask which build-up a seal is going into before we ask how many units, which is the method behind how we work.

What a certificate covers, and what it does not

Regulation (EU) No 305/2011 requires manufacturers to draw up a declaration of performance for a product covered by a harmonised specification, and to apply the relevant marking. That document is genuine and useful, and also narrow. It states what the manufacturer declares about the product. It cannot tell you the detail on your drawing was ever tested, because the manufacturer did not draw your building. The classification report ties a number to a configuration, and is the one worth asking for by name.

Regulation has moved the same way in several markets. The Building Safety Act 2022 in the United Kingdom established a building safety regulator, placed duties on accountable persons for higher-risk buildings, and included provisions on construction products liability, reaching manufacturer accountability and cost contribution orders where products proved defective. The practical message is plain: the evidence chain behind a fire-rated product is expected to be traceable, and whoever bought it is part of that chain. We keep that trail deliberately boring, which is what our approach to trust and quality is for.

Older and newer test regimes still sit side by side

BS 476-20:1987 sets out the method for determining the fire resistance of elements of construction and the general principles behind that older family of tests. Recent amendments to the English statutory guidance have moved away from those national classes towards BS EN 13501 for a number of applications, which is why refurbishment work in particular throws up specifications written to one regime and products certified to another. Neither situation is wrong on its own. The mistake is assuming an equivalence that nobody has demonstrated. When a requirement reaches us naming a BS 476 rating, we say so and ask which evidence route the approving authority will accept, rather than quietly supplying the nearest European equivalent and letting the difference surface later.

Buying across markets without losing the classification

An F rating and an EI classification are not translations of each other. They come from different methods with different criteria, and an approving authority in Nairobi, Berlin or Dublin will have its own view of which evidence it accepts. Several African markets recognise British or European practice, sometimes alongside product listings issued elsewhere, and the answer varies by project and by client. That is solvable, but only early, because a container of correctly made product carrying the wrong evidence is still the wrong delivery. So the first question on any enquiry is where the goods are going and who signs the job off, before anything about quantity or product name.

Where we fit, and where we do not

Our part happens before anyone is on site. We take a requirement, identify products whose manufacturers hold the test evidence the specification calls for, verify the supplier, and can arrange factory audit and pre-shipment inspection so what leaves the factory matches what was quoted. We hold no third-party certification ourselves and claim none. The certificates belong to the manufacturers whose product we supply, which is a different statement and an honest one.

We are a poor fit for three situations. A single item at short notice is better served by a local distributor. A fire strategy or a detail design is a fire engineer’s work, not ours. And if the paperwork needs to be flexible, the answer will be no. If none of those apply, send us the requirement with substrate, aperture and service details, and you will get a specific answer rather than a catalogue.