Timber in fire - Revision history

Jan: Remove links to pages that do not exist; retain displayed text (wiki-wide link audit).

2026-11-02T21:35:35Z

Remove links to pages that do not exist; retain displayed text (wiki-wide link audit).

← Older revision		Revision as of 22:35, 2 November 2026
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	The residual section can be warm even where it has not converted to char. Under natural exposure, White notes that heating during the cooling period can affect more than a narrow outer layer. Residual dimensions and temperature consequently describe different aspects of the member. Treating all uncharred wood as unchanged would omit that thermal history.<ref name="W_4-264" />		The residual section can be warm even where it has not converted to char. Under natural exposure, White notes that heating during the cooling period can affect more than a narrow outer layer. Residual dimensions and temperature consequently describe different aspects of the member. Treating all uncharred wood as unchanged would omit that thermal history.<ref name="W_4-264" />

	Member size influences the relationship between those effects. Large solid and glued timber members can retain a substantial interior while their exposed surfaces char. These members connect the subject to [[Mass timber]], although a calculation for one solid or glued member does not establish every assembly's behaviour. White's example methods specify material, dimensional and exposure limits.<ref name="W_4-261_4-264">White (2002), pp. 4-261–4-264.</ref>		Member size influences the relationship between those effects. Large solid and glued timber members can retain a substantial interior while their exposed surfaces char. These members connect the subject to Mass timber, although a calculation for one solid or glued member does not establish every assembly's behaviour. White's example methods specify material, dimensional and exposure limits.<ref name="W_4-261_4-264">White (2002), pp. 4-261–4-264.</ref>

	Loading remains part of the structural problem. White identifies the capacity of the remaining wood as a separate contribution from the membrane and the char depth. A member can lose structural function before all its wood is consumed. Conversely, visible charring does not by itself specify the time at which the applied load can no longer be carried.<ref name="W_4-257" /><ref name="W_4-260" />		Loading remains part of the structural problem. White identifies the capacity of the remaining wood as a separate contribution from the membrane and the char depth. A member can lose structural function before all its wood is consumed. Conversely, visible charring does not by itself specify the time at which the applied load can no longer be carried.<ref name="W_4-257" /><ref name="W_4-260" />

Emma: Revise Basic article against FSE writing guidelines: sourced explanations, examples and references (GPT-6)

2026-11-02T18:41:52Z

Revise Basic article against FSE writing guidelines: sourced explanations, examples and references (GPT-6)

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Emma: Revise Basic article against FSE writing guidelines: sourced explanations, examples and references (GPT-6)

2026-11-02T17:54:15Z

Revise Basic article against FSE writing guidelines: sourced explanations, examples and references (GPT-6)

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Sanne: Add diagrams fse-timber-in-fire-v1.svg, fse-timber-in-fire-v2.svg, fse-timber-in-fire-v3.svg (level-1 visual plan)

2026-11-02T07:07:12Z

Add diagrams fse-timber-in-fire-v1.svg, fse-timber-in-fire-v2.svg, fse-timber-in-fire-v3.svg (level-1 visual plan)

← Older revision		Revision as of 08:07, 2 November 2026
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	White describes normal wood, a pyrolysis zone and an outer char layer. As heating continues, the pyrolysis region advances into the member and the char thickens. Pyrolysis gases leave the surface and can undergo flaming combustion, while glowing combustion and mechanical disintegration gradually erode the outer char.<ref name="White-4-260" />		White describes normal wood, a pyrolysis zone and an outer char layer. As heating continues, the pyrolysis region advances into the member and the char thickens. Pyrolysis gases leave the surface and can undergo flaming combustion, while glowing combustion and mechanical disintegration gradually erode the outer char.<ref name="White-4-260" />
			[[File:fse-timber-in-fire-v1.svg\|thumb\|upright=1.5\|alt=Timber section with uncharred core, pyrolysis zone and char, with combustible gases leaving.\|Timber develops an uncharred core, pyrolysis zone and char. Based on White (2002), p. 4-260, Figure 4-11.2, redraw, do not copy.]]

	Kodur and Harmathy place the charring temperature for wood in the range 280 to 300 °C in their review. This is a material-specific range rather than a universal ignition threshold for every timber product and exposure. Pilot arrangement, heat flux and heat loss still influence actual ignition.<ref name="Kodur-Harmathy-1-164" /><ref name="Kanury-2-231">Kanury (2002), pp. 2-231–2-232.</ref>		Kodur and Harmathy place the charring temperature for wood in the range 280 to 300 °C in their review. This is a material-specific range rather than a universal ignition threshold for every timber product and exposure. Pilot arrangement, heat flux and heat loss still influence actual ignition.<ref name="Kodur-Harmathy-1-164" /><ref name="Kanury-2-231">Kanury (2002), pp. 2-231–2-232.</ref>
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	The standard average transverse-to-grain rate is approximately 0.6 mm/min in the sources. The rate parallel to grain is approximately twice that transverse rate. These conventions are widely used for standard fire exposure but do not represent every species, moisture condition and fire curve.<ref name="Kodur-Harmathy-1-164" /><ref name="White-4-261" />		The standard average transverse-to-grain rate is approximately 0.6 mm/min in the sources. The rate parallel to grain is approximately twice that transverse rate. These conventions are widely used for standard fire exposure but do not represent every species, moisture condition and fire curve.<ref name="Kodur-Harmathy-1-164" /><ref name="White-4-261" />
			[[File:fse-timber-in-fire-v2.svg\|thumb\|upright=1.5\|alt=Transverse charring 0.6 mm/min and parallel charring about 1.2 mm/min.\|Standard charring-rate convention by grain direction. Based on Kodur and Harmathy (2002), p. 1-164 and White (2002), p. 4-261.]]

	Reported study rates range from 0.137 to 0.85 mm/min, showing variation across specimens and test arrangements. Density and moisture content influence the rate, with the cited Douglas fir relationship showing decreases as density and moisture increase. The values used in a project should match the timber and exposure.<ref name="Kodur-Harmathy-1-164" /><ref name="White-4-261" />		Reported study rates range from 0.137 to 0.85 mm/min, showing variation across specimens and test arrangements. Density and moisture content influence the rate, with the cited Douglas fir relationship showing decreases as density and moisture increase. The values used in a project should match the timber and exposure.<ref name="Kodur-Harmathy-1-164" /><ref name="White-4-261" />
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	White reports that 13 mm gypsum board on wood beams reduced char depth by approximately 40% in two-hour tests, with only part of that benefit credited to the initial delay in char formation. This demonstrates protection through both delayed onset and reduced subsequent rate. The result belongs to the tested assembly.<ref name="White-4-260" />		White reports that 13 mm gypsum board on wood beams reduced char depth by approximately 40% in two-hour tests, with only part of that benefit credited to the initial delay in char formation. This demonstrates protection through both delayed onset and reduced subsequent rate. The result belongs to the tested assembly.<ref name="White-4-260" />
			[[File:fse-timber-in-fire-v3.svg\|thumb\|upright=1.5\|alt=Study range 0.137 to 0.85 mm/min with the standard average 0.6 marked.\|Reported charring rates vary around a standard average. Based on Kodur and Harmathy (2002), p. 1-164.]]

	Component-additive methods assign fire-resistance contributions to membranes and framing from test evidence. Fastener type and spacing can be critical, and codes limit how the method is applied. Adding insulation can improve a wall rating, while the position and attachment of insulation in floor or roof assemblies can change the result.<ref name="White-4-259">White (2002), pp. 4-259–4-260.</ref>		Component-additive methods assign fire-resistance contributions to membranes and framing from test evidence. Fastener type and spacing can be critical, and codes limit how the method is applied. Adding insulation can improve a wall rating, while the position and attachment of insulation in floor or roof assemblies can change the result.<ref name="White-4-259">White (2002), pp. 4-259–4-260.</ref>

Jan: New FSE wiki article: Timber in fire (written by Kimi Code CLI)

2026-11-02T00:36:34Z

New FSE wiki article: Timber in fire (written by Kimi Code CLI)

New page

'''Timber in fire''' describes the decomposition, charring and loss of structural capacity of wood exposed to heat. Timber is a combustible, char-forming material whose pyrolysis gases can feed flames while the remaining section loses density and strength. Fire resistance depends on species, moisture, section geometry, protection and the actual fire exposure.<ref name="White-4-260">White (2002), p. 4-260.</ref><ref name="Kodur-Harmathy-1-164">Kodur and Harmathy (2002), pp. 1-164–1-165.</ref>

Heating produces a char layer and volatile gases rather than a uniformly weakened version of the original timber. The char has virtually no load-bearing strength, so the uncharred core becomes the relevant structural section. Charring rate and residual cross-section are therefore central to assessment.<ref name="White-4-260" /><ref name="Kodur-Harmathy-1-164" />

Timber can also contribute to fire growth through its energy content and combustion products. Its behaviour in a small test and in a developed compartment fire can differ, making the actual exposure and installation essential to interpretation.<ref name="VR-4.4">Van Rossum (2027), §4.4.</ref><ref name="White-4-261">White (2002), pp. 4-260–4-261.</ref>

== Pyrolysis and degradation zones ==

[[Pyrolysis]] is thermal decomposition that breaks large wood molecules into smaller products, including combustible gases and char. It does not require oxygen at the decomposition site, although those gases can later burn after mixing with air. The original solid and the flame are therefore separate but coupled regions.<ref name="VR-3.1">Van Rossum (2027), §3.1.</ref><ref name="Beyler-Hirschler-1-111">Beyler and Hirschler (2002), p. 1-111.</ref>

White describes normal wood, a pyrolysis zone and an outer char layer. As heating continues, the pyrolysis region advances into the member and the char thickens. Pyrolysis gases leave the surface and can undergo flaming combustion, while glowing combustion and mechanical disintegration gradually erode the outer char.<ref name="White-4-260" />

Kodur and Harmathy place the charring temperature for wood in the range 280 to 300 °C in their review. This is a material-specific range rather than a universal ignition threshold for every timber product and exposure. Pilot arrangement, heat flux and heat loss still influence actual ignition.<ref name="Kodur-Harmathy-1-164" /><ref name="Kanury-2-231">Kanury (2002), pp. 2-231–2-232.</ref>

Moisture desorption occurs before and during decomposition and changes the energy required for heating. Wood density and moisture also affect charring, so a dry, constant-property model can be inadequate. Product form and permeability further influence gas movement and oxidation.<ref name="Beyler-Hirschler-1-112">Beyler and Hirschler (2002), p. 1-112.</ref><ref name="White-4-260" />

== Charring rate ==

[[Charring rate]] is the rate at which timber is converted to char, commonly expressed as depth per unit time. It determines how quickly the uncharred structural section shrinks. A constant rate can be a reasonable approximation for thick members under standard exposure, but actual fires can change it.<ref name="Kodur-Harmathy-1-164" /><ref name="White-4-260" />

The standard average transverse-to-grain rate is approximately 0.6 mm/min in the sources. The rate parallel to grain is approximately twice that transverse rate. These conventions are widely used for standard fire exposure but do not represent every species, moisture condition and fire curve.<ref name="Kodur-Harmathy-1-164" /><ref name="White-4-261" />

Reported study rates range from 0.137 to 0.85 mm/min, showing variation across specimens and test arrangements. Density and moisture content influence the rate, with the cited Douglas fir relationship showing decreases as density and moisture increase. The values used in a project should match the timber and exposure.<ref name="Kodur-Harmathy-1-164" /><ref name="White-4-261" />

Charring also rounds beam and column corners. White describes a common approximation in which the corner radius equals the char depth on the sides. Residual-section calculations should account for this shape loss rather than assuming the original sharp rectangle.<ref name="White-4-261" />

== Mass timber and residual section ==

[[Mass timber]] includes large engineered wood sections whose fire performance depends on the uncharred core and connections. Char has virtually no strength, so the original full section cannot be used in structural calculations once charring has developed. Residual geometry and material properties at temperature become decisive.<ref name="White-4-260" /><ref name="White-4-261" />

The [[Reduced cross-section method]] evaluates structural performance using the section remaining after subtracting charred material. Charring depth, corner rounding and the required load-bearing function determine that remainder. Protection that delays char onset or slows its advance increases the residual section at a given time.<ref name="White-4-260" /><ref name="White-4-261" />

Connections and adjacent elements can govern system performance even when the core retains capacity. Heat and deformation can weaken fasteners and change load paths, while different parts char at different rates. A structural assessment should include those details rather than treating the member as isolated material.<ref name="Fleischmann-Buchanan-4-242">Fleischmann and Buchanan (2002), p. 4-242.</ref><ref name="White-4-260" />

The remaining core can also be affected by temperature before charring reaches it. Mechanical properties at elevated temperature and internal moisture movement can change response. Zero-strength char and changing uncharred properties are separate considerations.<ref name="Rockett-Milke-1-29">Rockett and Milke (2002), p. 1-29.</ref><ref name="White-4-260" />

== Smouldering and char oxidation ==

[[Smouldering]] is flameless surface oxidation that can persist in porous char and timber after flaming declines. It produces heat and toxic products and can provide a later path back to flaming. Apparent extinction of open flame therefore does not prove that timber has stopped reacting.<ref name="Ohlemiller-2-200">Ohlemiller (2002), p. 2-200.</ref><ref name="Ohlemiller-2-208">Ohlemiller (2002), p. 2-208.</ref>

Char is carbon-rich and porous, making it susceptible to oxygen attack. Its oxidation supplies heat for continued smoulder propagation and can erode the protective layer. Char can insulate underlying timber and simultaneously sustain this surface combustion.<ref name="Beyler-Hirschler-1-110">Beyler and Hirschler (2002), p. 1-110.</ref><ref name="Ohlemiller-2-200" />

Solid wood has lower permeability than loose fibres, so its smouldering configuration differs from a porous insulation bed. Ohlemiller reports that a single wood layer may need about 10 kW/m² of additional heat input to sustain smouldering in the cited configuration. This is not a universal threshold for all timber products.<ref name="Ohlemiller-2-204">Ohlemiller (2002), p. 2-204.</ref>

Oxygen readmission and airflow can change the process after apparent suppression. Deep-seated char can reignite if it remains hot, and cooling such material can be difficult. Assessment after a fire should include the condition of the remaining char and core.<ref name="Ohlemiller-2-206">Ohlemiller (2002), p. 2-206.</ref><ref name="Gray-2-212">Gray (2002), p. 2-212.</ref>

== Fire resistance and protection ==

[[Fire resistance]] for timber members and assemblies depends on delaying char formation, limiting heat transfer and preserving the residual section and connections. Protective membranes can delay char onset and reduce subsequent charring rate. The complete assembly, not just the timber species, determines performance.<ref name="White-4-260" /><ref name="CVM2-64">Ministry of Business, Innovation and Employment (2025), p. 64.</ref>

White reports that 13 mm gypsum board on wood beams reduced char depth by approximately 40% in two-hour tests, with only part of that benefit credited to the initial delay in char formation. This demonstrates protection through both delayed onset and reduced subsequent rate. The result belongs to the tested assembly.<ref name="White-4-260" />

Component-additive methods assign fire-resistance contributions to membranes and framing from test evidence. Fastener type and spacing can be critical, and codes limit how the method is applied. Adding insulation can improve a wall rating, while the position and attachment of insulation in floor or roof assemblies can change the result.<ref name="White-4-259">White (2002), pp. 4-259–4-260.</ref>

Coatings and intumescent treatments can provide additional protection, but adhesion and deformation matter. White reports coated beams that improved less in full-scale testing than in earlier small-scale tests because bending caused adhesion problems. Product-scale evaluation is therefore necessary.<ref name="White-4-260" /><ref name="Beyler-Hirschler-1-110">Beyler and Hirschler (2002), p. 1-110.</ref>

== Fire exposure and modelling ==

A standard fire curve provides a controlled exposure for comparing assemblies, but real compartment fires vary in temperature and duration. Charring rate can change with that severity, so a standard 0.6 mm/min rate should not be used as an unqualified natural-fire constant. The exposure must be stated.<ref name="Kodur-Harmathy-1-164" /><ref name="Lie-4-201">Lie (2002), pp. 4-201–4-203.</ref>

Heat-transfer models can evaluate protective membranes and residual timber temperature, but they must also represent charring and panel deterioration. White notes that these physical changes complicate numerical methods. A conduction-only model may not capture the whole fire-resistance mechanism.<ref name="White-4-260" /><ref name="Rockett-Milke-1-29" />

Natural and parametric exposures can be used in performance-based analysis when supported by the model and data. Zone or compartment models supply the gas environment, after which heat transfer and structural analysis evaluate the member. Each stage needs appropriate validation.<ref name="White-4-260" /><ref name="Cadorin-Franssen-430">Cadorin et al. (2003), p. 430.</ref>

Sensitivity to species, density, moisture, section shape and protection should be made visible. Rounding char depth with excessive precision would hide those uncertainties. The structural conclusion should identify which assumptions control it.<ref name="VR-1.7">Van Rossum (2027), §1.7.</ref><ref name="White-4-261" />

== Limits and common misunderstandings ==

Timber does not simply melt away at one temperature. It decomposes into gases and char, loses section and can continue to smoulder. The residual structure and the combustion process must be assessed separately.<ref name="White-4-260" /><ref name="VR-3.1" />

Char is not a reliable structural material. Although it can insulate the core, it has virtually no load-bearing strength and can erode or oxidise. Structural calculations must use the residual uncharred section rather than crediting the full original member.<ref name="White-4-260" /><ref name="Kodur-Harmathy-1-164" />

The standard charring rate is not universal. Species, density, moisture, grain direction, protection and fire severity all affect it. Applying 0.6 mm/min without that context can misrepresent the residual section.<ref name="White-4-261" /><ref name="Kodur-Harmathy-1-164" />

Finally, a flame-retardant treatment does not necessarily provide fire resistance. It may delay ignition or reduce surface spread while offering limited improvement under deformation. The claim must be supported by the complete assembly and exposure.<ref name="White-4-260" /><ref name="CVM2-52">Ministry of Business, Innovation and Employment (2025), p. 52.</ref>

== Evidence and application ==

A timber assessment should begin with species, product form, density, moisture and section geometry. These determine the thermal response and how the residual section develops. Engineered products and connections can add further materials and failure paths that a solid-wood model would miss.<ref name="White-4-260" /><ref name="Kodur-Harmathy-1-156">Kodur and Harmathy (2002), p. 1-156.</ref>

Charring data should be tied to the exposure and grain direction. The familiar 0.6 mm/min transverse average and the approximate doubling parallel to grain are conventions for the cited standard exposure. Real fire severity, protective layers and product variation can produce different rates and should be addressed explicitly.<ref name="White-4-261" /><ref name="Kodur-Harmathy-1-164" />

Residual-section calculations should use the same char-depth convention as the structural analysis. Corner rounding, connections and any nonuniform charring can change the effective shape and load path. Subtracting an idealised rectangle without those details can overestimate the remaining capacity.<ref name="White-4-261" /><ref name="Fleischmann-Buchanan-4-242" />

Protection should be evaluated through both onset and rate. Gypsum and other membranes can delay char formation, but White's example also shows a reduced subsequent charring rate. Reporting only the initial delay would miss part of the protection's effect on the residual section at a given time.<ref name="White-4-260" />

Fire and smouldering history should be included after peak exposure. Hot char can continue to oxidise and can later support flaming, changing both the remaining section and the exposure of nearby objects. An analysis that stops when open flames disappear can therefore miss continuing degradation.<ref name="Ohlemiller-2-206" /><ref name="Ohlemiller-2-208" />

Test evidence should match the assembly and its deformation. Fasteners, panel attachment and bending can change membrane performance and expose timber earlier than expected. Small-scale material results do not remove the need to evaluate those full-scale conditions.<ref name="White-4-260" /><ref name="White-4-259" />

Model uncertainty should include the fire curve as well as material data. Standard exposure supports comparison, but natural fire severity can alter charring and protection. Sensitivity to exposure, density, moisture and residual geometry should be reported rather than hidden in a single char-depth value.<ref name="Lie-4-201" /><ref name="VR-1.7" />

A final review should separate the fire's fuel contribution from the member's structural performance. Timber can feed flames and smoke while the remaining core continues to support load, and those states change over time. Evaluating both is necessary for a complete account of timber in fire.<ref name="VR-4.4" /><ref name="White-4-260" />

The assessment should also distinguish material loss from loss of structural function. Charred material has virtually no strength, but the remaining core and connections can continue to support load for a period. Structural performance therefore depends on the residual system, not simply on whether charring is visible.<ref name="White-4-260" /><ref name="Fleischmann-Buchanan-4-242" />

For protected assemblies, the timing of each transition should be retained. Delayed char onset, a changed charring rate and later char oxidation affect the residual section in different ways. Combining them into one nominal protection factor would hide how the protection actually works.<ref name="White-4-260" /><ref name="Ohlemiller-2-206" />

For occupants and adjacent property, timber's combustion products must be assessed as well as its structure. Heat release, soot, carbon monoxide and smouldering can continue after the core has weakened, and external flaming can move the exposure elsewhere. The member's structural condition does not by itself describe the fire hazard.<ref name="VR-6.2">Van Rossum (2027), §6.2.</ref><ref name="Purser-2-85">Purser (2002), pp. 2-85–2-86.</ref>

A complete report therefore identifies the timber product, exposure, char-depth convention, residual geometry and structural criteria. It also states which protective and decay processes were included. This keeps the analysis tied to the actual assembly instead of treating the standard charring rate as a complete model.<ref name="White-4-261" /><ref name="VR-1.7" />

The fire exposure should also include its duration and spatial variation. Prolonged heating can advance pyrolysis and char even when the peak temperature is limited, and local hot regions can produce uneven residual geometry. A single average fire condition may not capture those effects on a large timber member.<ref name="Lie-4-201" /><ref name="White-4-260" />

A final assessment should connect the residual section with the required structural function and exposure period. The remaining core, connections and load paths must satisfy the selected criteria at that time. This makes reduced cross-section and fire resistance practical evaluation tools rather than descriptions of appearance alone.<ref name="White-4-261" /><ref name="CVM2-64">Ministry of Business, Innovation and Employment (2025), p. 64.</ref>

For final acceptance, the complete load and thermal history should be compared with the member's required function. This makes reduced cross-section and fire resistance practical evaluation tools rather than descriptions of appearance alone.<ref name="White-4-261" /><ref name="CVM2-64">Ministry of Business, Innovation and Employment (2025), p. 64.</ref>

== See also ==

* [[Strength reduction at elevated temperatures]]
* [[Structural fire engineering]]
* [[Mass timber]]

== Notes ==

<references />

== References ==

* Beyler, C. L., & Hirschler, M. M. (2002). Thermal decomposition of polymers. In P. J. DiNenno (Ed.), ''SFPE handbook of fire protection engineering'' (3rd ed.). National Fire Protection Association.
* Cadorin, J.-F., Pintea, D., Dotreppe, J.-C., & Franssen, J.-M. (2003). A tool to design steel elements submitted to compartment fires: OZone V2. Part 2: Methodology and application. ''Fire Safety Journal, 38'', 429–451.
* Fleischmann, C., & Buchanan, A. (2002). Analytical methods for determining fire resistance of concrete members. In P. J. DiNenno (Ed.), ''SFPE handbook of fire protection engineering'' (3rd ed.). National Fire Protection Association.
* Gray, B. (2002). Spontaneous combustion and self-heating. In P. J. DiNenno (Ed.), ''SFPE handbook of fire protection engineering'' (3rd ed.). National Fire Protection Association.
* Kanury, A. M. (2002). Flaming ignition of solid fuels. In P. J. DiNenno (Ed.), ''SFPE handbook of fire protection engineering'' (3rd ed.). National Fire Protection Association.
* Kodur, V. K. R., & Harmathy, T. Z. (2002). Properties of building materials. In P. J. DiNenno (Ed.), ''SFPE handbook of fire protection engineering'' (3rd ed.). National Fire Protection Association.
* Lie, T. T. (2002). Fire temperature-time relations. In P. J. DiNenno (Ed.), ''SFPE handbook of fire protection engineering'' (3rd ed.). National Fire Protection Association.
* Ministry of Business, Innovation and Employment. (2025). ''C protection from fire: Verification method C/VM2'' (2nd ed.). New Zealand Government.
* Ohlemiller, T. J. (2002). Smoldering combustion. In P. J. DiNenno (Ed.), ''SFPE handbook of fire protection engineering'' (3rd ed.). National Fire Protection Association.
* Rockett, J. A., & Milke, J. A. (2002). Conduction of heat in solids. In P. J. DiNenno (Ed.), ''SFPE handbook of fire protection engineering'' (3rd ed.). National Fire Protection Association.
* Van Rossum, E. (2027). ''Introduction to Fire Safety Engineering''. Fire Safety Academy.
* White, R. H. (2002). Analytical methods for determining fire resistance of timber members. In P. J. DiNenno (Ed.), ''SFPE handbook of fire protection engineering'' (3rd ed.). National Fire Protection Association.

[[Category:Structural Fire Engineering]]