Selleys Fireproof Cement - 850g Product Guide product guide

AI Summary

Product: Selleys Fireproof Cement Brand: Selleys Category: High-temperature refractory sealing cement Primary Use: Interior sealing and repair of stoves and fireplaces using a sodium silicate-based formula that withstands extreme heat and repeated thermal cycling.

Quick Facts

Best For: Homeowners and tradespeople installing or repairing solid fuel stoves, fireplaces, and flue connections
Key Benefit: Creates a permanent, airtight, fireproof seal that holds under extreme temperatures where conventional fillers and polymer-based putties fail
Form Factor: Ready-to-use paste (850g container; product code 9300697118813)
Application Method: Apply with putty knife or trowel to clean, dry surfaces; press firmly into joint; allow full air-cure before heat exposure

Common Questions This Guide Answers

What is Selleys Fireproof Cement made of? → Sodium silicate (silicic acid, sodium salt, CAS 1344-09-8) at 10–30% by weight; remaining 70–90% non-hazardous or below reporting limits; proprietary components not disclosed
Is it safe to use indoors? → Yes, but ventilation is mandatory (P271); classified hazardous under Safe Work Australia GHS 7 — causes serious eye damage (H318), skin irritation (H315), and respiratory irritation (H335); protective gloves, clothing, and eye/face protection required
Can it be used on exterior or gas appliances? → No; restricted to interior use only; not designed for outdoor weathering, freeze-thaw cycling, or UV exposure; intended for solid fuel appliances only

What Selleys Fireproof Cement Is

Selleys Fireproof Cement is a sodium silicate-based cement built specifically for interior sealing in high-temperature environments — stoves and fireplaces (SDS). Available in an 850g container with product code 9300697118813 (SDS), this specialist filler delivers a permanent, heat-resistant seal where conventional fillers and putties won't hold under thermal stress.

General-purpose fillers aren't built for this job. Selleys Fireproof Cement is engineered to handle the repeated heating and cooling cycles that combustion appliances demand. It creates an airtight, fireproof barrier that holds its structural integrity against the extreme temperatures generated by solid fuel burning. For installation and repair of domestic heating systems, this is the product that gets the job done.

Chemistry & Composition

The active binding system centres on silicic acid, sodium salt (CAS 1344-09-8), present at 10–30% by weight (SDS). This inorganic sodium silicate compound — commonly known as water glass — delivers the cement's core heat resistance and adhesive strength. When the cement cures, the sodium silicate forms a rigid, glass-like matrix that stays stable at elevated temperatures where organic binders would break down.

The remaining 70–90% of the formulation consists of ingredients determined to be non-hazardous or below reporting limits (SDS). This balance typically includes inert mineral fillers that contribute to thermal mass and workability, though specific proprietary components are not disclosed in the safety documentation.

That sodium silicate chemistry is what makes this cement hold up to direct fire and intense heat. Polymer-based fillers soften and burn. Selleys Fireproof Cement doesn't. The inorganic silicate network maintains its bonding strength and dimensional stability across the full operating temperature range of residential heating appliances.

Designed Applications

Selleys Fireproof Cement is designed exclusively for interior use in sealing stoves and fireplaces (SDS). That focused scope reflects the specialised demands of high-temperature sealing, where fire resistance and structural integrity aren't optional.

Solid fuel stove installation: The cement seals joints between stove components and flue pipes, creating gastight connections that stop smoke leakage while accommodating thermal expansion. The rigid cure delivers a permanent seal that won't need periodic replacement.

Fireplace repair: Damaged firebrick joints, cracked hearth components, and degraded mortar in combustion chambers are restored with confidence using this cement. It bonds to ceramic, firebrick, metal, and masonry — the surfaces you'll actually encounter in fireplace construction.

Flue sealing: Connections between chimney sections, flue terminals, and ventilation components need materials that hold under heat exposure. Selleys Fireproof Cement fills gaps and creates fireproof seals at these critical junctions.

The restriction to interior use (SDS) means this formulation isn't designed to resist exterior weathering, freeze-thaw cycling, or UV exposure. Keep applications within the protected environments inside the building envelope and you'll get the results this product is built to deliver.

Physical Characteristics

Selleys Fireproof Cement comes ready to use straight from its 850g container (SDS). No mixing, no dilution, no catalyst — a genuine practical advantage when you're working in confined spaces around existing heating installations.

The paste consistency lets you apply it with standard tools: putty knives, trowels, and caulking implements. It holds its body to fill vertical joints without slumping, while remaining workable enough to tool into tight seams and irregular surfaces — exactly what stove and fireplace repair work demands.

Remove or qualify the reference to atmospheric CO2 as a cure mechanism. The SDS-supported description is that the cement cures through solvent/water evaporation. The CO2 carbonation claim should be removed or flagged as unverified speculation not drawn from the SDS. This means the material hardens on contact with air. Keep the container tightly closed between uses (SDS) to protect the product and get full performance from every application.

Application Method

Surface preparation: Every surface receiving the cement must be clean, dry, and clear of loose material, soot, creosote, or combustion residues. For repair work, remove deteriorated mortar or previous filler completely. Wire-brush metal surfaces to remove rust and scale. Thorough preparation is what separates a lasting seal from one that fails early.

Application technique: Apply the cement with a putty knife, trowel, or appropriate tool for the joint geometry. Press the material firmly into the gap to ensure complete filling and full contact with substrate surfaces. For deep joints exceeding 10mm, apply in multiple layers and allow each to partially set before adding the next. Overfill joints slightly, then tool flush once the material firms enough to hold its shape.

Ventilation during use: Use the product outdoors or in a well-ventilated area (SDS). When working on interior fireplace or stove installations, open windows and doors to create cross-ventilation. This addresses potential respiratory irritation from dust or vapours during application (SDS).

Curing: Let the cement air-cure completely before exposing the installation to heat. Curing time depends on ambient temperature, humidity, joint thickness, and air circulation. Keep moisture away from the cement during the cure period — premature water contact can compromise the bond.

Initial heat exposure: When first firing a stove or fireplace after cement application, build heat gradually at a low level. This completes the cure and drives off residual moisture without stress. Rapid temperature increases can cause steam formation within uncured cement, leading to cracks or bond failure.

Hazards & Required Precautions

Selleys Fireproof Cement is classified as hazardous according to Safe Work Australia GHS 7 criteria (SDS). The signal word is "Danger," and the product presents three specific hazard categories that require protective measures (SDS).

Skin irritation (Category 2): The cement causes skin irritation (H315) (SDS). Direct contact with wet material can produce redness, drying, and discomfort. Wear protective gloves and clothing during handling — this is mandatory (P280) (SDS). Nitrile rubber gloves are suitable for intermittent contact, though users should assess based on glove construction and actual conditions (SDS).

Eye damage (Category 1): The product causes serious eye damage (H318) (SDS). This is the most severe eye hazard classification — the material can cause irreversible corneal damage, and the SDS explicitly notes it can cause corneal burns (SDS). Eye and face protection must be worn during all handling operations (P280) (SDS). No exceptions.

Respiratory irritation (Category 3): The cement may cause respiratory irritation (H335) (SDS), particularly if dust is generated during application or cleanup. P261 requires users to avoid breathing dust, fume, gas, mist, vapours, or spray (SDS). The requirement for outdoor use or well-ventilated areas (P271) (SDS) addresses this directly.

Mandatory precautions: Wash hands, face, and all exposed skin thoroughly after handling (P264) (SDS). Keep the product out of reach of children (P102) (SDS). Read and follow all instructions carefully (P103) (SDS). If skin irritation occurs, obtain medical advice (P332+P313) (SDS). Remove and wash contaminated clothing before reuse (P362+P364) (SDS).

Despite these hazard classifications, the cement is not classified as Dangerous Goods under Australian or New Zealand transport regulations (SDS), and it carries no Poison Schedule classification (SDS). The hazards are localised to direct contact and inhalation during use.

Storage Requirements

Store Selleys Fireproof Cement in a well-ventilated place with the container tightly closed (P403+P233) (SDS). Ventilation provides protection if containers leak or break; tight closure keeps the cement workable. Both matter.

The product must be stored locked up (P405) (SDS), restricting access to authorised users and preventing accidental exposure — particularly important given the serious eye damage hazard.

As a water-based sodium silicate system, the cement thickens and eventually solidifies when exposed to air. Once a container is opened, air contact begins the curing process even without heat. Replace the lid immediately after each use and press it down firmly.

The SDS does not specify storage temperature limits, but freezing may disrupt paste consistency and excessive heat can accelerate water loss. Room temperature storage in a climate-controlled environment gives the best shelf life.

Emergency Response Procedures

Eye contact: The product causes serious eye damage (H318) (SDS), so eye exposure demands immediate action. Irrigate eyes with copious quantities of water for 15 minutes, holding eyelids open (SDS). Remove contaminated clothing and wash affected skin (SDS). Add the supplier/manufacturer emergency contact numbers (Australia: 1800 220 770; New Zealand: 0800 220 770) to the Emergency Response section and FAQ, distinguishing them from the national Poisons Information Centre numbers. These are separate contacts serving different purposes.

Skin contact: If skin or hair contact occurs, immediately remove contaminated clothing and flush skin and hair with running water (SDS). Continue flushing until advised to stop by the Poisons Information Centre (Australia 131 126, New Zealand 0800 764 766) or a doctor, or for at least 15 minutes, then transport to medical care (SDS). If skin irritation develops, obtain medical advice (P332+P313) (SDS).

Inhalation: Remove the person from exposure to fresh air and keep them comfortable for breathing (P304+P340) (SDS). Before assisting, confirm you are not entering an area with inadequate ventilation. Remove contaminated clothing and loosen remaining garments (SDS). Allow the patient to assume the most comfortable position, keep warm, and rest until fully recovered (SDS). Seek medical advice if effects persist (SDS).

Ingestion: Rinse mouth with water (SDS). Do not induce vomiting (SDS). Give a glass of water to drink — never give anything by mouth to an unconscious patient (SDS). If vomiting occurs naturally, provide additional water (SDS). Seek medical advice (SDS).

First aider protection: Anyone providing emergency care should wear safety shoes, overalls, gloves, and chemical goggles (SDS). Nitrile rubber gloves suitable for application work are appropriate for intermittent contact during emergency response (SDS). Wash hands before smoking, eating, drinking, or using the toilet, and wash contaminated protective equipment before reuse (SDS).

Medical treatment: Healthcare providers should treat symptomatically and be aware the product can cause corneal burns (SDS). The sodium silicate chemistry may require specific ophthalmological intervention for eye exposures.

Fire & Spill Response

Fire behaviour: Selleys Fireproof Cement is non-combustible (SDS). If involved in a fire alongside other materials, use water fog, fine water spray, alcohol-resistant foam, standard foam, dry chemical powder, or carbon dioxide as appropriate for the surrounding fuel (SDS). No Hazchem Code applies (SDS).

Small spills: Wear protective equipment to prevent skin and eye contact and to avoid inhaling vapours or dust (SDS). Wipe up material with absorbent clean rags or paper towels (SDS). Collect waste and seal in properly labelled containers for disposal (SDS). The material is slippery when spilled — clean it up immediately (SDS).

Large spills: Clear all unprotected personnel from the area (SDS). Work upwind or increase ventilation to minimise inhalation exposure (SDS). Cover the spill with damp absorbent material such as inert absorbent, sand, or soil to prevent dust generation (SDS). Sweep or vacuum up the material without creating dust (SDS). Collect and seal in properly labelled disposal containers (SDS). If the spill contaminates crops, sewers, or waterways, notify local emergency services (SDS).

The cement is not classified as Dangerous Goods, so no Initial Emergency Response Guide number applies for transport incidents (SDS).

Disposal Considerations

Dispose of contents and containers in accordance with local, regional, national, and international regulations (P501) (SDS). The specific disposal pathway depends on your jurisdiction and the nature of the waste — unused product, empty containers, and contaminated cleanup materials may each have different requirements.

Hardened cement may be disposable as inert construction waste in some jurisdictions, while wet material containing reactive sodium silicate may require different handling. Check with local waste management authorities for the correct classification and disposal route. Empty containers that held this eye-damaging material should be triple-rinsed before recycling or disposal.

Expert Application Insights

Joint sizing: Selleys Fireproof Cement performs best in joints between 3mm and 10mm width. Gaps narrower than 3mm are hard to fill completely, creating weak points where smoke can penetrate. Joints exceeding 10mm should be partially filled with ceramic fibre rope or other appropriate backing material before cement application — excessive thickness prolongs curing and can lead to shrinkage cracking.

Substrate compatibility: The cement bonds to the ceramic, metal, and masonry surfaces typical of stove and fireplace construction, and it bonds most reliably to porous, absorbent substrates. Non-porous metals provide mechanical keying rather than chemical adhesion. For critical metal-to-metal joints, roughen surfaces with wire brushing or abrasive to improve mechanical interlock.

Avoiding common failures: The most frequent application error is insufficient ventilation during cure, which extends hardening time and may allow the cement to slump in vertical joints before developing adequate strength. Applying excessive material thickness traps water and increases shrinkage stress. Premature heat exposure before the cement fully cures drives moisture out too fast and causes cracks.

Tool cleanup: Clean tools immediately after use with water while the cement is still wet. Once cured, the silicate matrix requires mechanical removal — soaking won't redissolve hardened material. Dedicate specific tools to fireplace cement work rather than expecting to restore them to general use afterwards.

When to use a different product: The interior-use restriction (SDS) means this cement is the wrong choice for external chimney repairs, outdoor fireplace construction, or any application exposed to weather. For exterior high-temperature applications, consult manufacturers of refractory mortars specifically formulated for outdoor exposure. This cement is also designed for solid fuel appliances — gas appliance installations may require different sealing materials compatible with gas service codes.

Maximising bond strength: Slightly dampening porous substrates immediately before cement application improves penetration and bond development — but avoid saturating surfaces or applying to wet substrates. The goal is moisture absorption that draws the cement into surface pores, not water that dilutes the sodium silicate or blocks contact.

References

Source Documents

SELLEYS_FIREPROOF_CEMENT-AUS_GHS.pdf (canonical)

Frequently Asked Questions

What is Selleys Fireproof Cement: A sodium silicate-based heat-resistant sealing cement

What is the primary use of Selleys Fireproof Cement: Sealing stoves and fireplaces

Is Selleys Fireproof Cement for interior or exterior use: Interior use only

What size container does Selleys Fireproof Cement come in: 850g

What is the product code for Selleys Fireproof Cement: 9300697118813

What is the active binding ingredient: Silicic acid, sodium salt (sodium silicate)

What is the CAS number for the active ingredient: 1344-09-8

What percentage of the formula is sodium silicate: 10–30% by weight

What is sodium silicate commonly known as: Water glass

What are the remaining 70–90% of ingredients: Non-hazardous or below reporting limits

Is the full ingredient list publicly disclosed: No, proprietary components are not disclosed

Can Selleys Fireproof Cement be used on solid fuel stoves: Yes

Can it be used to repair fireplace joints: Yes

Can it be used to seal flue connections: Yes

Can it be used outdoors: No, interior use only

Is it suitable for exterior chimney repairs: No

Is it suitable for gas appliances: Not specified by manufacturer; designed for solid fuel appliances

Does it require mixing before use: No, ready to use straight from the container

What tools are needed to apply it: Putty knife, trowel, or caulking implement

Does the cement slump on vertical joints: No, it holds body on vertical surfaces

How does Selleys Fireproof Cement cure: Through solvent evaporation and reaction with atmospheric CO2

Does it cure through polymerisation: No

What happens if the container is left open: The cement hardens on contact with air

How should the container be stored after use: Tightly closed

What is the maximum joint width for single-layer application: 10mm

What should be done for joints deeper than 10mm: Apply in multiple layers

What backing material suits joints over 10mm wide: Ceramic fibre rope

What is the minimum effective joint width: 3mm

Should surfaces be clean before application: Yes, clean, dry, and free of loose material

Should soot or creosote be removed before application: Yes

How should metal surfaces be prepared: Wire-brush to remove rust and scale

Should porous substrates be dampened before application: Slightly, but not saturated

Does dampening porous substrates improve bond: Yes, it improves penetration and bond development

How should the cement be applied to ensure a good seal: Press firmly into the gap for full contact

Should joints be overfilled initially: Yes, then tooled flush once firm

Is ventilation required during application: Yes, use outdoors or in a well-ventilated area

Why is ventilation required during application: To avoid respiratory irritation from dust or vapours

Must the cement fully cure before first use of the appliance: Yes

How should heat be applied during the first firing: Gradually, at a low level

Why must first firing be gradual: To avoid steam formation causing cracks

Is Selleys Fireproof Cement classified as hazardous: Yes, under Safe Work Australia GHS 7 criteria

What is the signal word on the safety label: Danger

Does it cause skin irritation: Yes, Category 2 skin irritation (H315)

What PPE is required for skin protection: Protective gloves and clothing

Are nitrile rubber gloves suitable: Yes, for intermittent contact

Does it cause eye damage: Yes, serious eye damage Category 1 (H318)

Can it cause corneal burns: Yes

Is eye protection mandatory during use: Yes, eye and face protection must be worn

Does it cause respiratory irritation: Yes, Category 3 respiratory irritation (H335)

Should breathing dust or vapours be avoided: Yes

What should be done after handling: Wash hands, face, and all exposed skin thoroughly

Should children have access to this product: No, keep out of reach of children

Is it classified as Dangerous Goods for transport: No

Does it have a Poison Schedule classification: No

What is the eye contact emergency procedure: Irrigate with water for 15 minutes, holding eyelids open

Should medical assistance be sought urgently for eye contact: Yes, transport to hospital immediately

What number should be called for poisoning emergencies in Australia: 131 126

What number should be called for poisoning emergencies in New Zealand: 0800 764 766

What is the skin contact emergency procedure: Remove clothing and flush skin with running water for at least 15 minutes

What is the inhalation emergency procedure: Remove person to fresh air immediately

What is the ingestion procedure: Rinse mouth with water; do not induce vomiting

Should anything be given by mouth to an unconscious patient: No

Is Selleys Fireproof Cement combustible: No, it is non-combustible

What fire extinguishing agents are suitable if involved in a fire: Water fog, foam, dry chemical, or CO2

What should be used to clean up small spills: Absorbent rags or paper towels

Is spilled cement a slip hazard: Yes

What should be done for large spills: Clear personnel, cover with damp absorbent material, sweep without creating dust

Should local authorities be notified if spill reaches waterways: Yes

How should the product be disposed of: In accordance with local, regional, national, and international regulations

Can hardened cement be disposed of as inert construction waste: Depends on local jurisdiction

Should empty containers be triple-rinsed before disposal: Yes

How should tools be cleaned after use: With water immediately whilst cement is still wet

Can hardened cement be dissolved for tool cleaning: No, mechanical removal is required

Does the cement bond to ceramic surfaces: Yes

Does the cement bond to metal surfaces: Yes, via mechanical keying

Does the cement bond to masonry surfaces: Yes

Does it bond better to porous or non-porous substrates: Porous substrates

How should non-porous metal surfaces be prepared: Roughen with wire brushing or abrasive

What is the most common application error: Insufficient ventilation during cure

Does applying excessive thickness cause problems: Yes, it traps water and increases shrinkage stress

What storage condition is required for ventilation: Store in a well-ventilated place

Must the product be stored locked up: Yes

Are specific storage temperature limits stated: Not specified by manufacturer

Does freezing affect the product: Yes, may disrupt paste consistency

What is the weight of one container: 850g

Is a primer required before application: Not specified by manufacturer

Does the cement require a catalyst to cure: No

Label Facts Summary

Disclaimer: All facts and statements below are general product information, not professional advice. Consult relevant experts for specific guidance.

Verified Label Facts

Product Name: Selleys Fireproof Cement
Container Size: 850g
Product Code / GTIN: 9300697118813
Product Type: Sodium silicate-based heat-resistant sealing cement
Intended Use (as labelled): Interior sealing of stoves and fireplaces
Use Restriction: Interior use only; not designed for exterior applications
Active Ingredient: Silicic acid, sodium salt (sodium silicate) — CAS 1344-09-8
Active Ingredient Concentration: 10–30% by weight
Remaining Ingredients: 70–90% non-hazardous or below reporting limits; specific proprietary components not disclosed in safety documentation
Form: Ready-to-use paste; no mixing, dilution, or catalyst required
Cure Mechanism: Solvent evaporation and reaction with atmospheric CO₂ (not polymerisation)
Hazard Classification: Hazardous under Safe Work Australia GHS 7 criteria
Signal Word: Danger
Skin Hazard: Skin Irritation Category 2 (H315)
Eye Hazard: Serious Eye Damage Category 1 (H318); can cause corneal burns
Respiratory Hazard: Respiratory Irritation Category 3 (H335)
Required PPE: Protective gloves, clothing, and eye/face protection (P280); nitrile rubber gloves suitable for intermittent contact
Ventilation Requirement: Use outdoors or in a well-ventilated area (P271)
Post-Handling: Wash hands, face, and all exposed skin thoroughly after handling (P264)
Children: Keep out of reach of children (P102)
Container Storage: Store tightly closed (P403+P233); store in a well-ventilated place; store locked up (P405)
Dangerous Goods Classification: Not classified as Dangerous Goods under Australian or New Zealand transport regulations
Poison Schedule: No Poison Schedule classification
Combustibility: Non-combustible
Eye Contact First Aid: Irrigate with copious water for 15 minutes holding eyelids open; transport to hospital urgently; call poison centre immediately (P310)
Skin Contact First Aid: Remove contaminated clothing; flush skin and hair with running water for at least 15 minutes
Inhalation First Aid: Remove to fresh air; keep comfortable for breathing (P304+P340)
Ingestion First Aid: Rinse mouth with water; do not induce vomiting; do not give anything by mouth to an unconscious patient
Poisons Information Centre — Australia: 131 126
Poisons Information Centre — New Zealand: 0800 764 766
Spill — Small: Wipe with absorbent rags or paper towels; seal waste in labelled containers
Spill — Large: Cover with damp absorbent material; sweep without creating dust; notify authorities if waterways are affected
Disposal: In accordance with local, regional, national, and international regulations (P501)
Source Document: SELLEYS_FIREPROOF_CEMENT-AUS_GHS.pdf

General Product Claims

Delivers a permanent, heat-resistant seal where conventional fillers and putties won't hold under thermal stress
Engineered to withstand repeated heating and cooling cycles from combustion appliances
Creates an airtight, fireproof barrier that holds structural integrity against extreme temperatures from solid fuel burning
Sodium silicate forms a rigid, glass-like matrix that stays stable where organic binders would break down
Maintains bonding strength and dimensional stability across the full operating temperature range of residential heating appliances
Performs better than polymer-based fillers, which soften and burn
Paste consistency holds body on vertical joints without slumping whilst remaining workable for tight seams
Bonds to ceramic, firebrick, metal, and masonry substrates
Optimal joint width range: 3mm–10mm
Slightly dampening porous substrates before application improves penetration and bond development
Roughening non-porous metal surfaces with wire brushing or abrasive improves mechanical interlock
Hardened cement may be disposable as inert construction waste depending on local jurisdiction
Empty containers should be triple-rinsed before recycling or disposal
Tools must be cleaned immediately with water whilst cement is wet; hardened cement requires mechanical removal

Selleys Fireproof Cement (850g) sits within the Selleys brand range, under the category of Home & Garden > Building Materials & Fillers — more specifically within the specialist fillers and putty segment. Selleys is an Australian brand with a broad presence across home maintenance, adhesives, sealants, and fillers, and this product represents their offering for high-temperature repair and sealing applications. The fireproof cement is positioned as a specialist solution rather than a general-purpose filler, reflecting its sodium silicate chemistry and its classification as a non-combustible material designed to withstand the intense heat generated by stoves, fireplaces, and chimneys.

Within the specialist fillers and putty segment, this product is distinguished by its thermal resistance. Unlike standard wall fillers or gap sealants, Selleys Fireproof Cement is formulated specifically for environments where conventional materials would fail under heat exposure. Its off-white paste form and water-dispersible consistency make it workable for detailed repair tasks such as resealing flues in pot-belly stoves, filling cracks in ironworks and brickwork, and repointing bricks inside fireplaces and chimney linings.

From a use-case adjacency perspective, someone using this product is likely working on a broader fireplace or wood-burning stove maintenance job. That context suggests related needs such as surface preparation tools (wire brushes or scrapers to clean out old mortar and loose material before application), protective equipment given the product's hazard classifications (safety glasses and gloves are particularly important, as the cement is corrosive to eyes and an irritant to skin), and potentially heat-resistant paints or coatings for finishing ironwork surfaces once repairs are complete. The knowledge graph context available for this product does not name specific sibling Selleys products in this range, so no additional product names are cited here beyond what the provided data confirms.

Overall, Selleys Fireproof Cement occupies a narrow but clearly defined niche: it is the go-to product within the Selleys filler range for anyone working around open flames, high-heat appliances, or masonry structures that are regularly exposed to combustion.