Optimizing Fire Safety: The Essential Role of Fire-Resistant Expansion Seals in Chinese Fire Doors Fire doors represent a crucial aspect of passive fire protection systems within buildings, serving to effectively isolate the source of a fire, prevent the spread of flames, and thereby safeguard both lives and property. Among the key components of fire doors […]
Tag Archives: Working Principles of Normally Open and Normally Closed Fire Doors
Working Principles of Normally Open vs. Normally Closed Fire Doors
YK Commercial Door Company explains the critical differences between these two fire door operational modes, essential for proper life safety system design:
1. Normally Closed Fire Doors (Standard Operation)
Working Principle:
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Default State: Permanently closed/latched
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Activation: Stays closed during fire events
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Purpose: Maintain compartmentation 24/7
Key Components:
✔ Automatic door closers (EN 1154 certified)
✔ Positive-latching mechanisms
✔ Intumescent seals
Applications:
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Stairwell doors (NFPA 80 requirement)
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Elevator lobby partitions
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Hazardous material storage rooms
Advantages:
✓ Constant fire barrier
✓ Lower maintenance
✓ Cost-effective
2. Normally Open Fire Doors (Hold-Open Systems)
Working Principle:
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Default State: Held open electromagnetically
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Activation: Releases to close upon:
• Fire alarm signal (24V DC drop)
• Power failure (fail-safe close)
• Smoke detector trigger
Key Components:
✔ Electromagnetic holders (EN 1155 compliant)
✔ Swing-free floor closers
✔ Fire-rated wiring systems
Applications:
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Hospital corridors (for gurney access)
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Retail spaces with high foot traffic
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Accessibility-compliant routes
Advantages:
✓ Unobstructed daily operations
✓ Meets ADA/EN 16005 accessibility
✓ Automatic emergency response
3. Comparative Analysis
Feature | Normally Closed | Normally Open |
---|---|---|
Energy Use | None | Continuous 24V supply |
Maintenance | Annual checks | Quarterly system tests |
Installation Cost | $200-500/door | $800-1,500/door |
Compliance | Required in 90% of cases | Special applications only |
4. Critical Installation Requirements
For Normally Open Systems:
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Coordination with fire alarm system (compatible interfaces)
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Backup power for electromagnetic systems (per IBC 1008.1.9)
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Clear signage “Fire Door – Keep Clear” (ADA/BS 5499 compliant)
YK’s Technical Support:
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BIM coordination for interface points
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Approved hardware packages (DoorGuard™ systems)
5. Smart Evolution: Hybrid Systems
YK’s Innovation:
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IoT-enabled doors that:
• Monitor open/close status in real-time
• Self-test closing force monthly
• Integrate with building management systems
Certification:
UL 10C + EN 54-25 (fire alarm compatibility)
Specification Guidance:
For most applications, normally closed doors are preferred. Normally open systems should only be used where continuous access is operationally essential and properly maintained.
YK Fire Door: China’s Premier Fire-Rated Door ManufacturerAs a leading fire door supplier in China, YK Fire Door Industry Co., Ltd. combines cutting-edge engineering with globally recognized certifications to deliver fire-resistant doors that redefine safety standards. Our steel fire-rated doors, manufactured in state-of-the-art Yunnan facilities, integrate military-grade materials and intelligent automation—positioning China as the global […]