A product datasheet reports how something performed in one test, under one configuration, against one fire. Approving passive fire protection means knowing which fire, which configuration, and which properties the test deliberately left out.
Two Fires, and They Are Not Versions of Each Other
Fire protection for an office block and fire protection for a process module are not the same product rated to different durations. They are answers to different fires, and the difference is in how fast the heat arrives.
A cellulosic fire is what burns in a building: wood, paper, textiles, furnishings. It develops over time, and the standard test curves for it rise correspondingly, which is why building fire ratings are expressed in periods of an hour or two under a gradually climbing temperature.
A hydrocarbon fire does not develop. It arrives. UL 1709, the rapid rise fire test for protection materials for structural steel, subjects the protection to 1093°C within five minutes of the start of the test, and holds it there for the remainder. A product that performs for two hours under a building curve may fail in minutes under that one, because its protective mechanism never gets the time it was designed around.
A two hour rating under a building fire curve and a two hour rating under a hydrocarbon curve are not comparable numbers. They describe survival of two different events.
Then there is jet fire, which is a third case rather than a worse version of the second. A pressurised release burning as a directed flame applies mechanical erosion along with heat, and a material that chars effectively under pool fire conditions can have that char stripped away by the jet. ISO 22899-1, Determination of the resistance to jet fires of passive fire protection materials, Part 1: General requirements, exists precisely because pool fire performance does not predict it.
What the Test Actually Covers
The most useful thing to understand about a PFP certificate is the scope of the test behind it, and ISO 22899-1 is unusually explicit about its own limits.
What it covers: A method for determining the resistance of passive fire protection materials and systems to jet fires, indicating how they behave and providing performance data under the specified conditions. Clause 7 addresses test specimens for systems, including assemblies, cable transit systems and pipe penetration seals.
Explicitly excluded: Weathering. Ageing. Shock and impact resistance. Explosion resistance. Smoke production. None of these is assessed by the test, so a jet fire certificate says nothing whatever about them.
A geometric limit: The standard states that complete I-beams and columns cannot be tested to it, because their presence disrupts the characteristics of the jet. Specimens are therefore not the finished structural member.
The standard’s own caveat: Results do not guarantee safety and should form one input to a fire risk assessment. Specimen dimensions can be smaller than real structures, and the imposed loads do not necessarily coincide with those of an actual jet fire.
Edition matters: The current edition is ISO 22899-1:2021, the second, which replaced the 2007 edition.
Read the exclusions together and the practical consequence becomes clear. A product with excellent jet fire data may have no demonstrated durability at all under tropical ultraviolet exposure, marine salt loading and thermal cycling, because the test that produced the data explicitly set those questions aside. In a Malaysian offshore environment, where the protection will spend a decade or more weathering before it is ever asked to resist a fire, that gap is the whole question.
The certificate says the material resisted a jet fire. It says nothing about whether the material will still be on the steel in eight years, because the standard removed that question from its own scope.
Why the Datasheet Is Not the Approval
The reason specifying PFP from a product datasheet fails is that performance belongs to a tested configuration rather than to a product name.
The standards test materials and systems, and the configuration recorded in a test is the configuration the result describes: the thickness applied, the steel section used, any mesh or reinforcement present, and the condition of the surface it was applied to. Change any of those on site and the result is no longer evidence about what was installed. A thickness that was adequate on one section size is not automatically adequate on another, and the standards have moved toward testing across section sizes precisely because the relationship is not linear.
The layers above and below the PFP belong to the same question. A PFP coating sits on a primer and usually carries a topcoat for weathering and appearance, and those layers affect both adhesion and behaviour in fire. Approving a PFP product without establishing which primer and topcoat the performance was demonstrated with leaves the actual installed build-up unevidenced, whatever the datasheet says about the middle layer.
The correct question to a supplier is therefore not what the product achieves, but what configuration the certificate covers: the test standard and its edition, the fire curve, the substrate and section, the thickness, the reinforcement, and the surrounding layers. Anything applied outside that envelope is an engineering judgement rather than a certified system, and it should be recorded as one.
Verification On Site
PFP is the one coating where the thickness argument is a life safety argument, and it has to be settled while the work is accessible.
The fourth and fifth items cause most of the trouble. Reinforcement becomes invisible the moment the next pass is applied, so an unrecorded mesh is an unverifiable mesh. And terminations at connections and penetrations are fiddly, time-consuming and routinely rushed at the end of a programme, which places the weakest protection at the points where structural members meet.
In-Service, Which Is Where the Exclusions Bite
Because the fire tests exclude weathering and ageing, the durability case has to be made separately, and it has to be maintained.
PFP that has cracked, disbonded or lost its topcoat has an unknown remaining performance. It has not necessarily failed, but nobody can say it has not, because the evidence base was a sound system in a test rig. Water ingress behind PFP is worse still, since it corrodes the steel the protection was applied to defend and the damage is concealed by the protection itself, which is the same blind spot that a disbonded coating creates for cathodic protection.
That argues for treating PFP as inspectable rather than permanent: condition surveys on a defined cycle, repair procedures agreed with the system supplier in advance rather than improvised at a shutdown, and records that tie each repair back to the qualified configuration. Our industrial painting and coating service handles PFP on that basis, and the systems supplied under it carry fire test certification appropriate to the exposure they are specified for.
None of this makes PFP difficult. It makes it a system rather than a product, which is a different purchasing decision and a different acceptance regime, and the distinction is worth settling before the steel is in place rather than after a fire has asked the question.
Frequently Asked Questions
What is the difference between cellulosic and hydrocarbon fire ratings?
The rate at which heat arrives. A cellulosic fire, burning building materials, develops over time and the test curves rise gradually. A hydrocarbon fire reaches extreme temperature almost immediately, and UL 1709 reflects this by subjecting protection to 1093°C within five minutes of the test starting and holding it there. A product rated for hours under a building curve may fail in minutes under the hydrocarbon curve.
Is jet fire the same as a hydrocarbon pool fire?
No. A jet fire is a pressurised release burning as a directed flame, which applies mechanical erosion along with heat and can strip away char that would survive pool fire conditions. ISO 22899-1, now in its 2021 second edition replacing the 2007 edition, exists specifically because pool fire performance does not predict jet fire resistance.
Does a fire test certificate cover durability?
No, and ISO 22899-1 is explicit about it. The standard excludes weathering, ageing, shock and impact resistance, explosion resistance and smoke production from its scope. It also states that results do not guarantee safety and should be one input to a fire risk assessment. Durability in a tropical marine environment has to be established separately from the fire performance data.
Why can PFP not be approved from a product datasheet?
Because the standards test materials and systems, and the result describes the configuration that was tested: thickness, steel section, reinforcement, substrate condition and the surrounding layers. The right question to a supplier is which configuration the certification covers, including the test standard and edition, the fire curve, the section size and the primer and topcoat the performance was demonstrated with. Anything installed outside that envelope is engineering judgement rather than certified performance.
Sources: ISO 22899-1:2021, Determination of the resistance to jet fires of passive fire protection materials, Part 1: General requirements, second edition June 2021 superseding ISO 22899-1:2007, including the scope covering materials and systems, the exclusions of weathering, ageing, shock and impact, explosion resistance and smoke production, the Clause 7 treatment of system test specimens, the statement that complete I-beams and columns cannot be tested due to disruption of the jet, and the introduction’s caveat that results do not guarantee safety · UL 1709, Rapid Rise Fire Tests of Protection Materials for Structural Steel, including the 1093°C within five minutes exposure, full-scale and small-scale column testing, and optional jet fire and multi-temperature analysis provisions
MarineCraft Journal
Get the next briefing in your inbox
Safety protocols, offshore training, regulation and market analysis, written for Malaysia’s maritime and offshore industry. No sales pitches.
We use your address only to send MarineCraft Journal. Unsubscribe any time. See our Privacy Policy.