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Plan Notes 155 Pleasant St 2016-11-30 (2)SECTION 1022 EXIT ENCLOSURES 1022.1 Enclosures required. Interior exit stairways and interior exit ramps shall be enclosed with fire barriers constructed in accordance with Section 707 or horizontal assemblies constructed in accordance with Section 712, or both. Exit enclosures shall have a fire-resistance rating of not less than 2 hours where connecting four stories or more and not less than 1 hour where connecting less than four stories. The number of stories connected by the exit enclosure shall include any basements but not any mezzanines. Exit enclosures shall have a fire-resistance rating not less than the floor assembly penetrated, but need not exceed 2 hours. Exit enclosures shall lead directly to the exterior of the building……. 1022.4 Penetrations. Penetrations into and openings through an exit enclosure are prohibited except for required exit doors, equipment and ductwork necessary for independent ventilation or pressurization, sprinkler piping, standpipes, electrical raceway for fire department communication systems and electrical raceway serving the exit enclosure and terminating at a steel box not exceeding 16 square inches (0.010 m2). Such penetrations shall be protected in accordance with Section 713. There shall be no penetrations or communication openings, whether protected or not, between adjacent exit enclosures. This section specifically lists the items that are allowed to penetrate a vertical exit enclosure. This is consistent for all types of exit enclosures, including stair or ramp vertical exit enclosures and exit passageways (see Section 1023.6). In general, only portions of the building service systems that serve the exit enclosure are allowed to penetrate the exit enclosure. As indicated in the commentary to Section 1020.1, standpipe systems are commonly located in the exit stair enclosures. If two exit enclosures are adjacent to one another, there must be no penetrations between them, thereby limiting the chances of smoke being in both stairwells. This requirement is not intended to prohibit windows in the exterior walls of stairways that are not required to be rated. This section and Section 1022.5 are meant to work together. 707.5 Continuity. Fire barriers shall extend from the top of the floor/ceiling assembly below to the underside of the floor or roof sheathing, slab or deck above and shall be securely attached thereto. Such fire barriers shall be continuous through concealed spaces, such as the space above a suspended ceiling. 707.5.1 Supporting construction. The supporting construction for a fire barrier shall be protected to afford the required fire-resistance rating of the fire barrier supported. Hollow vertical spaces within a fire barrier shall be fireblocked in accordance with Section 717.2 at every floor level. In general, fire barriers must be supported by construction having an equivalent fire-resistance rating. If the supporting structure is a primary structural frame (see definition) and supports a fire barrier wall more than two stories in height, the fire-resistance rating for the supporting structure must be protected by the individual encasement method in Section 704.3. If the supporting members are a secondary structural member, then the supporting structure can be protected by membrane protection as in Section 712 for horizontal assemblies. The intent of this requirement is to prevent the effectiveness of the assembly from being circumvented by a fire that threatens the supporting elements. The requirement for the supporting construction to be fire-resistance rated applies to buildings of all types of construction, even to buildings of Type IIB, IIIB and VB construction for all fire barrier walls except those separating incidental use areas. Fire barrier walls will usually be built on top of a floor and will terminate at the floor above. Should a fire barrier wall, as in the case of some shaft walls, be constructed through a floor, any hollow space within that wall could provide a passage for fire or smoke and, therefore, must be fireblocked as specified in the last sentence of Section 707.5.1. Any hollow vertical spaces within fire barrier walls must be fireblocked in accordance with Section 717.2.2. Definition, SECONDARY MEMBERS: The following structural members shall be considered secondary members and not part of the primary structural frame: 1. Structural members not having direct connections to the columns; 2. Members of the floor construction not having direct connections to the columns; and 3. Bracing members other than those that are part of the primary structural frame. This term works in conjunction with the term “primary structural frame” to distinguish which elements of a building’s structure needs to receive various levels of fire resistance protection. These requirements are found in Table 601 and Sections 704. 707.7 Penetrations. Penetrations of fire barriers shall comply with Section 713. In order to maintain the integrity of the fire barrier, penetrations into and through the fire-resistance-rated wall must be properly protected. Acceptable methods for various penetrations of fire barriers are identified in Sections 713.3 through 713.3.1.2. The provisions of Section 707.7.1 must be used when the penetration is into an exit enclosure or exit passageway. 707.7.1 Prohibited penetrations. Penetrations into an exit enclosure or an exit passageway shall be allowed only when permitted by Section 1022.4 or 1023.6, respectively. This section reminds the code user that although the penetration firestop systems do provide protection for the penetration, the code prohibits most penetrations through exit enclosures. Only penetrations of items, such as sprinkler piping, necessary ductwork for stair pressurization and electrical conduit that serve the exit enclosure, are allowed. There can never be a penetration through a fire barrier that separates an adjacent exit enclosure (see Sections 1022.4 and 1023.6). SECTION 708 SHAFT ENCLOSURES 708.1 General. The provisions of this section shall apply to shafts required to protect openings and penetrations through floor/ceiling and roof/ceiling assemblies. Shaft enclosures shall be constructed as fire barriers in accordance with Section 707 or horizontal assemblies in accordance with Section 712, or both. SECTION 713 PENETRATIONS 713.1 Scope. The provisions of this section shall govern the materials and methods of construction used to protect through penetrations and membrane penetrations of horizontal assemblies and fire-resistance-rated wall assemblies. This section addresses the specific requirements for maintaining the integrity of fire-resistance-rated assemblies at penetrations. The provisions of this section apply to penetrations of fire-resistance-rated walls (see Section 713.3), fire-resistance-rated horizontal assemblies (see Sections 713.4.1 and 713.4.1.4) and nonfire-resistance-rated assemblies (see Section 713.4.2). Penetrations of fire-resistance-rated assemblies range from combustible pipe and tubing to noncombustible wiring with combustible covering to noncombustible items, such as pipe, tube, conduit and ductwork. Each type of penetration requires a specific method of protection, which is based on the type of fire-resistance-rated assembly that is penetrated and the type of penetrating item. To determine the type of penetration protection required, the first step is to identify whether the penetrated assembly is a fire-resistance-rated wall; a fire-resistance-rated horizontal assembly or a nonfire- resistance-rated horizontal assembly. Next, identify the type of penetrating item in the applicable section and determine the applicable method of penetration protection necessary. 713.3 Fire-resistance-rated walls. Penetrations into or through fire walls, fire barriers, smoke barrier walls and fire partitions shall comply with Sections 713.3.1 through 713.3.3. Penetrations in smoke barrier walls shall also comply with Section 713.5. In order to maintain the integrity of the fire-resistance- rated wall assembly (fire walls, fire barriers, smoke barriers and fire partitions), penetrations into and through the rated assembly must be properly protected. Acceptable protection methods for various penetrations of wall assemblies are identified in Sections 713.3.1 through 713.3.4. Additionally, penetrations of smoke barriers must meet the test requirements for air leakage given in Section 713.5. 713.3.1 Through penetrations. Through penetrations of fire-resistance-rated walls shall comply with Section 713.3.1.1 or 713.3.1.2. Exception: (N/A) Because combustible materials have a greater propensity to spread fire through a penetration, the requirements for combustible penetrating items are considerably more restrictive than for noncombustible penetrating items, which can use the exception. Penetration of fire-resistance-rated walls by cables, wires, pipes, tubes, conduits and vents represent a weak link in the continuity of the required fire-resistance rating and are required to be properly protected. These penetrations are to be protected with materials that will maintain the integrity of the wall for the duration of the required fire-resistance rating… 713.3.2 Membrane penetrations. Membrane penetrations shall comply with Section 713.3.1. Where walls or partitions are required to have a fire-resistance rating, recessed fixtures shall be installed such that the required fire-resistance will not be reduced. Exceptions: (N/A) Membrane penetrations are defined in Section 702 as “an opening made through one side (wall, floor or ceiling membrane) of an assembly.” Therefore, they are different from a through penetration in that they do not pass through the entire assembly. Membrane penetrations are treated similar to through penetrations; namely, noncombustible conduits, pipes and tubes that penetrate only one membrane of a fire-resistance-rated wall assembly are required to have the annular space protected in accordance with Section 713.3.1 or comply with the exception of that section. Combustible penetrations through only one membrane of a wall assembly would require either a tested assembly (see Section 713.3.1.1) or a through-penetration firestop system that complies with Section 713.3.1.2 for the penetrated membrane.