Fireproof Duct Materials EI 45 – EI 120: Classification & Application
In ventilation and air conditioning systems, especially in projects with strict fire prevention and fighting requirements, the use of EI fireproof ducts is mandatory according to standards. Not only does it ensure effective fire prevention and insulation, this type of pipe also requires special construction materials, suitable for corresponding fire resistance times such as EI 45, EI 60, EI 90 or EI 120.
So what materials are EI 45 – 120 fireproof ducts made from? Let’s find out more details with Eusteel in the following article.
1. What is EI fireproof air duct?
EI fireproof air duct is a type of air duct capable of:
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Prevents fire from penetrating (E – Integrity)
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Heat transfer compartment (I – Insulation)
The EI index (for example: EI 60, EI 90, EI 120) represents the time the duct can withstand fire and heat under fire conditions without structural destruction or causing excessive heat transfer.
2. Classification of duct materials EI 45 – 120
1. Main core: Galvanized steel or stainless steel
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Galvanized steel (GI): Commonly used, from 0.75mm to 1.2mm thick.Stainless steel (SUS 304, SUS 430): Used in highly corrosive environments, chemical and food factories.
2. Fireproof insulation
Depending on the fire resistance time (EI 45 – EI 120), the insulation layer is selected as follows:
| Level EI | Main insulation material | Standard thickness |
|---|---|---|
| EI 45 – EI 60 | Rockwool is heat resistant to 250 – 600°C | 25 – 30 mm |
| EI 90 | Ceramic Fiber is heat resistant to 800 – 1000°C | 30 – 40 mm |
| EI 120 | High quality ceramic wool or intumescent coating material | 50 mm trở lên |
3. Outer covering (finishing cover)
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Galvanized corrugated iron / Galvanized steel mesh: Wrap outside to fix the fireproof cotton layer.
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Silicone / aluminum coated glass fabric: Waterproof, increases aesthetics.
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Intumescent coating material: Used in active fire protection systems, it will expand when exposed to high heat to protect the inner layer.
3. Phân phối vật liệu theo cấp độ EI
| Cấp EI | Materials used | Describe |
|---|---|---|
| EI 45 – EI 60 | GI corrugated iron + mineral wool | Popular for homes and small offices |
| EI 90 | GI/Stainless steel sheet + ceramic cotton | For apartments and commercial centers |
| EI 120 | Stainless steel + high quality ceramic cotton + puff coating | Used for factories, chemical warehouses, basements, high-rise buildings |
4. Requirements when constructing EI air ducts
When using fireproof materials for EI ducts, it is necessary to comply with the accompanying construction standards:
- Install fireproof air valves at wall and floor penetration points
- Use heat-resistant gaskets at joints to avoid gas leaks and fire spread
- Hang the pipe with a fireproof threaded rod or heat-resistant support frame
- Fire resistance tested according to EN 1366 or TCVN 9311-1
5. Eusteel – Providing EI 45 – 120 fireproof air ducts that meet inspection standards
At Eusteel, we manufacture and supply EI fire-resistant air ducts with full EI levels from 45 to 120 minutes, using materials that meet technical standards and fire protection testing. Our experienced technical team will advise on materials suitable for each location and project budget.
