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For intensive use and safety, security steel door are most often used to protect exterior openings of commercial buildings. Popular for its resilience and adaptability, are also a good choice for cost-effective, low maintenance.
Benefits
One of the major options for securing the outside entrance of a building is a security door commercial security. Resistant to extreme heat and cold, rain and humidity, steel security doors will not deteriorate when exposed to the elements, and offer greater isolation and lower maintenance than standard wood steel security door.
Construction
Commercial steel security doors are constructed with a standard core of polystyrene or polyurethane, combined with a resin component for strength and covered with a steel wood door. The safety door can be customized according to the type of building to be made. For example, if a security gate must withstand heat, like a fire, a mineral fiber core would be used. This would enable it to withstand high temperatures and flames to give a fire stainless steel door resistance of 20 minutes or three hours, according to security gate of the Republic. To police stations, security doors bulletproof available galvannealed steel and tested to UL752 - Standard for Bullet-proof material - in eight levels of room door protection.
Safety / Ventilation
Generally, a steel security door regular flush on both sides, with window openings. In some cases, such as stairs or high traffic areas, a small window is added for safety to avoid the sudden opening of the security door. The grilles are also available where ventilation is necessary, according to information available WiseGEEK steel door.