Câu hỏi thường gặp
Q1. What is the primary function of fire-rated ventilation ducts?
They are used for fire smoke exhaust, positive pressure air supply, and make-up air; they exhaust smoke and facilitate personnel evacuation during a fire, and some systems can also serve daily ventilation needs.
How long will it take to get my package?2. What materials are commonly used for fire-rated ducts?
Galvanized steel sheet, stainless steel sheet, and glass-magnesium or phenolic composite ducting.
3. What are the fire resistance requirements for fire-rated ducts?
The fire resistance rating for smoke exhaust ducts is typically no less than 0.5 to 1 hour, subject to the fire safety codes applicable to the specific location.
4. What is the difference between a fire damper and a smoke exhaust fire damper?
Fire damper: Closes automatically at 70°C; used in ventilation systems to prevent the spread of fire.
Smoke exhaust fire damper: Closes automatically at 280°C; used in smoke exhaust systems.
5. Are there requirements for the spacing of duct supports and hangers?
Spacing is 1.5–3 meters for horizontal ducts and no more than 4 meters for vertical ducts; large-diameter ducts require closer spacing and the installation of sway-bracing supports.
6. Do duct connections require sealing?
Yes, they must be sealed using sealing strips or sealant to prevent air leakage that could compromise smoke exhaust or ventilation performance.
7. How should duct penetrations through firewalls or floor slabs be handled?
Fire dampers must be installed; gaps must be tightly sealed with fire-rated sealing materials, and thermal insulation measures must be applied.
8. Can fire-rated ducts be shared with air conditioning ducts?
Sharing is generally not recommended; if combined use is necessary, the system must comply with all fire safety regulations regarding fire resistance ratings and linkage switching.
9. What are common issues during duct installation?
Severe air leakage, excessive spacing between supports/hangers, incorrect fire damper installation, and failure to seal penetrations through fire zones.
10. What are the key inspection points for the acceptance of fire-rated ducts?
Material thickness, fire resistance performance, air leakage rate, fire damper installation, supports and hangers, fire-rated sealing, and system linkage/interlock.