Fire resistance ratings

Fire resistance rating—The time period that a specific fireproofing design will protect structural supports for equipment, piping and so forth from collapse, when exposed to a fire of specified intensity. The fire intensity is usually represented by a time-temperature curve. 

Fire Resistance Rating of Wall Number and Fire Resistance Rating of Door(s) and Shutters 

Chapter 7 Fire resistant-rated construction. This chapter addresses the separation requirements between rooms/compartments in buildings and between buildings, and also deals with insulation. 

Fire Resis- 4 hour fire resistance rating. 

Fire Barrier Typically non-load bearing walls with a fire resistance rating of 2 to 3 hours. 

Traditionally, the IWUIC code contained requirements for fire resistance-rated construction, but the 2009 edition also contains alternate requirements based on ignition-resistant materials, which 

I Fire resistive and noncombustible construction Subclassified into two categories where structural frame carries a fire resistance rating of 3 or 4 hours Floor construction is 2 or 3 horn- rated Roof construction is 1V4 or 2 hour rated 

NFPA 288 Standard Methods of Fire Tests of Floor Fire Door Assemblies Installed Horizontally in Fire Resistance-Rated Floor Systems 

Structural steel supports for within-unit process transfer lines should be fireproofed with a 1 - to 2-hour fire resistance rating. 

Fire Partitions are similar to Fire Barriers in every respect except they have a 1 to 2 hour fire rating. Fire partitions are generally used to further subdivide areas and can also be supported by fire resistance rated columns, floors, and ceilings. 

Electrical conductors are normally insulated for protection and avoidance of electrical shorting. Typical insulating materials are plastics that can readily bum with toxic vapors. The NEC specifies certain fire resistant rating to electrical cables to lessen the possibility of cable insulation ignitability and fire spread. 

Chapter 6 Types of construction. The permission to use combustible materials or the type of fire resistance ratings are a function of whether the building is constructed completely, or primarily, of noncombustible materials. 

The increasing use of fiber optics for electronic communications poses critical communications risks. The fire resistant requirements of fiber optical cables are currently similar to the requirements of fire resistant ratings applied to electrical cables within the specifications of the NEC. 

Refer also to the containment section of this chapter for a discussion of liquid containment methods. Ramping may need to be provided at floor level openings in fire resistance rated barriers serving as a containment scheme component to prevent liquid travel under the fire door. 

For enclosed process structures, open outside stairs may be used for an exit, but require protective separation from the interior of the building by walls with the same fire resistance rating as required for enclosed stairs. This construction should extend vertically from the ground to a point 10 ft (3 m) above the topmost landing of the stairs or to the roofline, whichever is lower, and to a point not less than 10 ft (3 m) horizontally. 

For equipment, tanks, and vessels containing flammables or heated combustible liquids, their steel structural supports, legs, and anchors should normally be fireproofed for a 2-hour fire resistance rating. Some typical examples of where fireproofing should be applied are  

Dry-type transformers are preferred for installations inside buildings. Where oil-insulated transformers are installed indoors, they should be separated from adjacent areas by fire barriers of 3-hour fire resistance rating if the transformers capacity or rating exceeds either of the following  

Polyetheretherketone PEEK is a high-temperature, crystalline engineering TP used for high performance applications such as wire and cable for aerospace applications, military hardware, oil wells and nuclear plants. It holds up well under continuous 450°F (323° C) temperatures with up to 600°F (316° C) limited use. Fire resistance rating is UL 94 V-0 it resists abrasion and long-term mechanical loads. 

Generally, chemical warehouses whose contents classify them as hazardous occupancies should be constructed of fire resistive or noncombustible construction. Fire resistive construction should consist of materials that will withstand the anticipated fire exposure of a given duration without structural failure. The following standards and test methods are commonly used to establish selected fire resistance ratings  

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