As high-rises multiply, fire risk is well known, and fire trucks can’t reach those heights, so fire equipment is a must. The fire-rated roller shutter protects life and property, but not every “fire-rated” shutter actually resists fire. A real one does, and the difference from an ordinary shutter is that besides the fire barrier it also stops fire and smoke from spreading, because it’s made of fire-resistant material. The making and the materials differ too.
For high-rise installation, the shutter is the inorganic-fabric fire-rated type; steel fire-rated shutters generally don’t suit indoor high-rise partitions. What is the inorganic-fabric shutter made of?
a. Top layer: blue fabric, a flame-retardant blue fiberglass cloth. Good from −70°C to 230°C.
b. Fire-resistant cotton: sits under the flame-retardant fabric. A new fire material made by a special process; it barely burns and self-extinguishes after the source is gone.
c. The fiber flame-retardant tech: inorganic and organic polymers compound and interpenetrate, so the inorganic flame retardant sits in the organic fiber at nano scale or as an interpenetrating network. You keep the fiber strength and get low toxicity, low smoke, no melt-drip, and no environmental harm. The fiber and textile gain both flame retardancy and anti-drip.
d. Refractory felt: made from calcined bauxite, spun and set. Low thermal conductivity and heat capacity, good thermal stability and impact resistance, low tensile strength, strong insulation, fire resistance, and sound absorption. Withstands 1100°C–1260°C.Ordinary shutters use stainless steel or PVC, hollow or transparent. They look far better than fire-rated shutters but fall well short on safety. Which to buy is the customer’s call; it comes down to what you actually need.
Fire-rated shutters have fire ratings; ordinary ones don’t.
F1: 1.50h. F2: 2.0h. Composite steel shutter: F3: 2.50h; F4: 3.00h. The national standard for steel shutter fire grading doesn’t require measuring the unexposed-side temperature rise, nor uses it to judge the rating. In recent years mist-type and evaporative mist-type steel shutters appeared; by the higher rules, when used as a compartment element the unexposed-side temperature rise must be the judging condition. To tell the two grading bases apart: a shutter that meets all judging conditions including unexposed-side temperature rise, with a rating ≥3.0h, is called a premium shutter. Any shutter in fire testing that does not use unexposed-side temperature rise as the judging condition is an ordinary shutter.