Technical Library
Answers to the passive fire questions that actually come up on projects.
Overview
Every question here is one somebody has actually put to us — on site, in a submission, or halfway through a job when the detail stopped matching the building. The answers are written the way we would give them over the phone: what governs the decision, what would change it, and what evidence you need before anyone can call it.
Why the answer is rarely just a number
Passive fire questions rarely have one answer that survives contact with a real building. The substrate, the service, the opening, the age of the building and the project requirement all move it. An answer that gives you a single number without telling you what would change that number has told you very little.
None of this is project-specific advice. It will tell you what governs a decision and what evidence the decision needs. It will not tell you that your installation complies, because that cannot be established from a distance.
By subject
- Fire doors — Doorset identification, tags and labelling, clearances, hardware, inspection frequency, repair versus replacement, asbestos-era doors.
- Penetrations and fire stopping — Substrates, service types, annular space, mixed services, sleeves and insulation, tested-system evidence, common rejection causes.
- Structural fire protection — Sprayed and board systems, intumescent coatings, section factors, damage and repair, and asbestos in older sprayed protection.
- Ducts, dampers and transits — Duct protection, damper types and access, cable transit systems and the boundaries between them.
- Bulkheads and enclosures — Shaft and enclosure construction, board systems, junctions and penetrations through them.
- Inspection and baseline surveys — What an inspection can and cannot establish, baseline data, asset registers, older buildings.
- Rectification — Defect registers, prioritising work in occupied buildings, close-out evidence.
- Records and handover — Registers, labelling, photographic records, what a handover pack should contain.
- Questions that cut across every service — Which NCC edition applies, when a variation needs review, what to do before inspecting an older building, when the installed system cannot be identified, when drawings and site conditions disagree.
Who answers these
Every article in this library is reviewed and signed by Scott Cunningham, our Compliance Manager — a carpenter by trade with a degree in project management and more than twenty-five years in passive fire across the UK and Australia. His name and the date of the last review are printed at the top of each one, along with the date the next review is due.
That is not a formality. An article whose review date has passed does not publish on this site at all — the build refuses it — so a page you can read is a page still in review date.
Where an answer depends on drawings, test evidence or a specific site condition, it goes to a person rather than to a general answer. If a submission needs it, we will tell you who checked it and when.
Cannot find it
Then ask. Send the question with whatever you have — a photograph, a drawing, a defect line — and you will get an answer from someone who has dealt with it before.
Technical library
Every question we have answered.
Can a fire door be repaired?
Sometimes. A repair is only a good answer when the defect is understood and the repair method is supported for the actual doorset and the component involved.
Scott CunninghamCan damaged structural fire protection be repaired?
Often, if the existing system can be identified and its repair instructions or supporting evidence cover the damage. A patch is not automatically valid just because it uses the same-looking material.
Scott CunninghamCan different services share one fire-stopped opening?
Sometimes, but only where the supporting system evidence covers the combined arrangement. A mixed-service opening cannot be justified by placing several unrelated single-service products into the same opening.
Scott CunninghamCan new cables be added to an existing cable transit?
Often, where the specific system, its capacity and the proposed service arrangement support the change. Adding cables beyond what the evidence covers turns a maintainable transit into an undocumented penetration.
Scott CunninghamCan old sprayed fire protection on structural steel contain asbestos?
Yes. Sprayed coatings applied to steel between roughly the 1930s and the 1970s were often asbestos-based, and fire protection of beams and columns was one of their main uses. Appearance alone cannot tell you. Because sprayed coatings are friable, the safest assumption on a building of that era is that the material is asbestos until an assessment says otherwise.
Scott CunninghamCan you install a digital lock or access control on a fire door?
Sometimes, but it depends on the exact doorset, the hardware, how it is fixed, how cables are routed, and how the door is required to close and latch. There is no useful universal yes or no.
Scott CunninghamCan you modify a fire door?
Potentially, but not by assumption. Drilling, cutting, glazing, adding hardware or changing a component can affect the evidence that supports the doorset.
Scott CunninghamDo fire doors need seals?
It depends on the doorset and the project requirement. Different seals do different jobs, and a missing or damaged seal cannot be assessed properly without knowing what the doorset was designed to use.
Scott CunninghamFire-rated duct wrap or board enclosure: what changes the choice?
The choice between wrap and board turns on the duct duty, geometry, space available, supports, access requirements, the surrounding construction and which arrangements the evidence covers.
Scott CunninghamHow do access panels and service penetrations affect a fire-rated enclosure?
Access panels and penetrations are common ways an enclosure stops matching its evidence. Both have to be part of the supported arrangement rather than cut in afterwards.
Scott CunninghamHow do plastic pipe penetrations differ from metal pipe penetrations?
Plastic and metal pipes behave differently in a fire, so penetration systems are selected differently. The pipe material, diameter, wall thickness, orientation and the fire-stopping components used with it are all part of the tested configuration.
Scott CunninghamHow do you identify a suspect asbestos fire door?
Age, construction and records can raise suspicion, but appearance alone cannot establish that a door is asbestos-free or asbestos-containing. Do not disturb a suspect leaf to find out.
Scott CunninghamHow do you manage passive fire defects in an occupied building?
Build the programme around the building's operation as well as the technical repair. Group the work by location and access, identify shutdowns and permits early, protect occupied areas, and keep open defects visible until they are closed out.
Scott CunninghamHow do you turn a passive fire defect register into a rectification scope?
Preserve the client's original asset IDs and wording, then group the items by system, observable condition, likely repair pathway, access and evidence quality. A register becomes a workable scope at the point where the repeatable repairs separate from the exceptions.
Scott CunninghamHow does pipe insulation affect a fire-stopping detail?
Pipe insulation can materially change a penetration detail. Its material, thickness, continuity through the opening, and how the fire-stopping system interfaces with it can all affect which tested or assessed configuration applies.
Scott CunninghamHow does structural steel fire protection work?
Steel loses strength as it heats. Protection systems slow that heating so the member holds its required performance for the required period. The system is selected against the member, the design requirement and the supporting evidence — not against a general idea of thickness.
Scott CunninghamHow is the required thickness of steel fire protection determined?
Required thickness comes from the system's test or assessment evidence read against the member and the design requirement. There is no universal table, and any figure published without its system and conditions is misleading.
Scott CunninghamHow should inaccessible passive fire items be reported?
Record the access limitation and the area it affects, as a finding in its own right. Do not turn "not inspected" into "acceptable" because the asset could not be reached.
Scott CunninghamHow should passive fire before-and-after photographs be taken?
Take two photographs, not one: a wider shot showing where the item sits, then the technical close-up. A close-up of sealant, a door edge or a coating with no location context is weak evidence, because nobody can tell afterwards where it was taken.
Scott CunninghamSprayed protection, intumescent coating or board encasement: what is the difference?
Sprayed, intumescent and board systems solve the same problem differently, and differ in cost, appearance, application conditions, environmental tolerance, programme and the evidence behind them. The choice is a design decision, not a finish preference.
Scott CunninghamWhat do gaps around a fire door mean?
Clearances matter, but the correct limit is not a number to guess from a photograph. The acceptable condition depends on the applicable doorset evidence, the location around the leaf, and the project requirements.
Scott CunninghamWhat do labels and asset IDs prove — and what do they not prove?
A label proves that someone created an identification record, and possibly that there is a link to a schedule or a system reference. It does not prove that the current installation matches that evidence, or that it has not been altered since.
Scott CunninghamWhat do opening size and annular space change?
Opening dimensions, and the space between the service and the edge of the opening, can change which fire-stopping configuration is supported. A product can be suitable in one geometry and unsupported in another.
Scott CunninghamWhat does a fire door tag tell you?
A tag can help identify a fire doorset and connect it to records, but a tag on its own does not prove the current installation is acceptable. The door may have been altered after it was tagged.
Scott CunninghamWhat does AS 1905.1 mean for fire doors?
AS 1530.4 is the fire test. AS 1905.1 is the standard that governs the doorset itself — how a fire-resistant doorset is constructed, identified and installed into the surrounding construction. Once the building is in service, routine inspection and maintenance of fire and smoke doors is AS 1851. The door is not the leaf. It is the leaf, the frame, the hardware, the seals, any glazing and the fixing into the wall, tested together and relied on together.
Scott CunninghamWhat does AS 4072.1 mean for service penetrations?
AS 1530.4 is the fire test. AS 4072.1 is the standard that governs how a test result is applied — the materials, components and methods used to protect service penetrations and control joints in elements required to have an FRL, and the conditions under which a tested prototype can be relied on for the thing actually built. It is the link between a test report in a folder and a hole in a wall.
Scott CunninghamWhat evidence is useful for closing a passive fire defect?
Evidence closes a defect when it connects the original finding to the completed work and to the technical basis relied on. In practice that means the defect reference and its location, photographs before and after, the system used and the evidence behind it, who carried out the repair and when, and any variation from the original method. The exact set varies by system and by contract.
Scott CunninghamWhat happens when cables are added to an existing penetration?
Adding cables can change the configuration the original penetration system was tested or assessed for. The new cable loading, bundle size, spacing and any disturbance to the existing seal all need checking against the system evidence.
Scott CunninghamWhat if the installed passive fire system cannot be identified?
Treat a missing identity as an evidence problem rather than a workmanship one. Collect labels, product markings, drawings, schedules, photographs and the geometry of the opening. If the system still cannot be established, do not close the issue by naming the most likely product.
Scott CunninghamWhat information do you need to select a fire-stopping system?
The minimum useful information is what the separating element is, what service passes through it, the size and shape of the opening, the required fire resistance, and any insulation, sleeve or support condition that changes the tested configuration.
Scott CunninghamWhat is a cable-transit system?
A cable-transit system is a framed arrangement that lets cables pass through a fire-resisting element and be changed later without rebuilding the seal, within what the tested system permits.
Scott CunninghamWhat is a fire door and what is a doorset?
A fire door is not only the door leaf. The performance of the opening depends on the complete doorset and on how it is installed in the surrounding construction.
Scott CunninghamWhat is a fire-rated bulkhead or enclosure?
A fire-rated bulkhead or enclosure is a documented fire-resisting construction built around services, structure or geometry. The construction, not the board, is what carries the performance.
Scott CunninghamWhat is a passive fire baseline survey?
A baseline survey creates a usable starting record for an existing building or portfolio: what assets and conditions can be located, what records exist, what can be observed, and what is missing before a maintenance or rectification programme is built on top of it.
Scott CunninghamWhat is a service penetration fire-stopping system?
A service penetration fire-stopping system is the complete arrangement used where a service passes through a fire-resisting wall or floor. It includes the service, the opening, the separating element, the fire-stopping materials and the installation geometry supported by test or assessment evidence.
Scott CunninghamWhat is a steel section factor and why does it matter?
A section factor expresses how much heated surface a steel member has relative to how much steel there is to absorb the heat — in Australian practice the exposed surface area divided by the mass of the member, expressed in square metres per tonne. European and ISO documents use a surface-area-to-volume form instead, so a figure taken from an overseas source is not directly comparable with the tables in an Australian assessment. A high section factor means a member heats quickly for its size and needs more protection; a low one means the opposite. It is one of the inputs that determines the protection thickness required, alongside the design requirement and the tested system. Who establishes it on a given project is a responsibility question rather than a technical one, and it is worth settling early.
Scott CunninghamWhat is the difference between a fire damper and a smoke damper?
A fire damper is intended to restrict the spread of fire where a duct or opening passes through a fire-resisting barrier, and typically closes in response to heat. A smoke damper is intended to control the movement of smoke, and is generally operated by a detection or control system rather than by heat alone. Combination fire and smoke dampers perform both functions. Which one an opening requires depends on the building design, the system duty and the evidence supporting the installed assembly — and a damper being present in an opening does not tell you which requirement it was installed to meet.
Scott CunninghamWhat is the difference between a tested system and a product?
A fire-stopping product is a material or component. A tested or assessed system is the complete configuration in which that product is supported to perform. Buying the right brand does not prove the installation matches the system evidence.
Scott CunninghamWhat is the difference between an observation and a compliance conclusion?
An observation is what the inspector can see, measure or confirm from records. A compliance conclusion compares the actual condition against the applicable requirement and the evidence behind it, and may need information a visual inspection cannot supply. Reporting the second as though it were the first is how a register becomes unsafe to rely on.
Scott CunninghamWhat makes a fire-resisting duct system different from ordinary ductwork?
A fire-resisting duct system is a tested or assessed construction in which duct, protection, joints, supports, access and penetrations work together. Adding insulation to ordinary ductwork does not create that system.
Scott CunninghamWhat records should exist for a fire door?
Good records let the next person identify the asset, understand what was installed or repaired, and see the evidence behind that work. The exact handover package depends on the project and the contract.
Scott CunninghamWhat records should exist for a fire-stopped penetration?
Useful records let the next person identify the penetration, understand what services and system were installed, and connect the physical opening back to the supporting evidence. The exact record set depends on the project and the contract.
Scott CunninghamWhat records should exist for structural, duct, damper, transit and enclosure work?
Records should let the next person identify the member or asset, understand what was installed, and see the evidence relied on. Exact fields depend on system and contract.
Scott CunninghamWhat should a fire door inspection report contain?
A useful report identifies the asset, records what was observed, distinguishes fact from assumption, shows supporting photographs, and gives a next action another person can act on.
Scott CunninghamWhat should a passive fire asset register contain?
Enough for another person to find the item, understand what it is, see its status and connect it to the relevant evidence. In practice: a unique asset ID, the location described well enough to walk to, the item type, the system installed and the evidence reference behind it, the installer and date, the current condition or status, and photographs. A register that cannot be searched and reused is a list, not a register.
Scott CunninghamWhat should a passive fire inspection record?
For each item: the asset or location, what was observed, the relevant evidence or the gap in it, and a next action. "Pass" or "fail" without the reason is rarely enough for whoever has to price or rectify it afterwards.
Scott CunninghamWhat should a penetration defect report contain?
A useful penetration defect report identifies the opening, records the actual condition, separates observation from assumption, shows the evidence gap, and gives a next action another person can price or investigate.
Scott CunninghamWhat should be checked around a fire damper installation?
The damper, the opening, the installation method, the connection or breakaway detail, access provision, orientation, and — where applicable — the control and commissioning arrangement. A label on the damper says nothing about the installation around it.
Scott CunninghamWhat should be included in a passive fire handover pack?
A location and asset schedule, the installed or rectified condition of each item, the supporting system information, photographs, and any outstanding exceptions. It should be searchable and reusable, not a folder of product brochures.
Scott CunninghamWhat should you check when a fire door will not close or latch?
Start with what is physically stopping the door. A door that does not reach the closed and latched position needs the cause identified — not the closer simply wound up until it slams.
Scott CunninghamWhat should you do before inspecting passive fire in an older building?
Establish the building's era and check the asbestos register before anyone inspects anything. Two separate dates matter here and they are easily confused. In Western Australia a workplace building constructed on or before 31 December 2003 requires an asbestos register — that is the date that triggers the obligation, not the 1980s or 1990s. The exemption runs the other way: a workplace built after that date can go without a register only where no asbestos has been identified and none is likely to be present. Separately, sprayed protection applied to structural steel from roughly the 1930s into the 1970s is friable, so it is treated as the highest priority on site — friable material releases fibres when disturbed rather than only when cut, and era alone makes it suspect rather than proven. The material question comes first; the fire-protection question waits behind it.
Scott CunninghamWhat should you do when drawings, schedules and site conditions disagree?
Do not quietly choose the document that makes the work easiest. Record the conflict, identify which document creates the project requirement, and send the actual site condition into the agreed resolution process before anything is installed.
Scott CunninghamWhen can passive fire defects be grouped as repeatable conditions?
Group them only where the assets, the construction and the supported repair condition are genuinely the same. Similar-looking photographs are not enough.
Scott CunninghamWhen does a passive fire site condition need technical review?
Escalate when the site condition does not fit the available evidence, or when a proposed change affects the configuration that evidence covers. The test is not how unusual the condition looks, it is whether anything on file supports it.
Scott CunninghamWhen does a passive fire variation need technical or engineering review?
A variation needs technical review the moment it changes the tested configuration — a different substrate, a different service, a bigger opening, a substituted component, a detail altered to suit what is actually buildable. Three outcomes are possible: the existing evidence already covers it, the system manufacturer can support it by assessment, or it needs a fire engineer. Which one applies is a technical question, and it has to be settled before the variation is priced rather than after it is installed.
Scott CunninghamWhen should a fire door be replaced?
Replacement becomes the cleaner option when the existing doorset is too damaged, too altered, or too poorly documented for a supported repair to make technical or commercial sense.
Scott CunninghamWhich NCC edition applies to my project?
In Western Australia, that depends on when the building permit application was made. NCC 2025 took effect in WA on 1 May 2026, and during the transition most permit applications may be assessed against either NCC 2025 or NCC 2022 Amendment 2. Amendment 2 is the operative form of the 2022 edition — it commenced 29 July 2025 and superseded the earlier 2022 versions, so "NCC 2022" on its own is no longer precise enough to write on a permit. NCC 2025 becomes mandatory for applications from 1 May 2027.
Scott CunninghamWhy do wall and floor penetrations need different details?
Wall and floor penetrations are different orientations with different construction, support and installation conditions. A detail tested in one orientation is not automatically transferable to the other.
Scott Cunningham
Drawings, photos or a defect report in front of you?
Send what you already have. We will tell you what else is needed before the work can be reviewed, priced or booked for site inspection.