Western Steel Erection plan review notes

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1003.3.3.6 1997 UNIFORM BUILDING CODE 1003.3.4.4 2.Handrails may have starting or volute newels within the first tread EXCEPTIONS:1.Group R.Division 3 Occupancies. on stairways in Group R,Division 3 Occupancies and within individual 2.Protection of exterior wall openings is not required where the dwelling units of Group R,Division 1 Occupancies. exterior openings in the interior stairway are protected by fixed or self- The handgrip portion of handrails shall not be less than closing fire assemblies having a three-fourths-hour fire-protection 11/4 inches (32 mm) nor more than 2 inches (51 mm)in cross- rating- sectional dimension or the shape shall provide an equivalent grip- 3.Protection of openings is not required for open parking garages ping surface. The handgrip portion of handrails shall have a conforming to Section 405. smooth surface with no sharp comers.Handrails projecting from a 1003.3.3.11 Stairway to roof.In buildings four or more stories in wall shall have a space of not less than 11/2 inches (38 mm) height, one stairway shall exte4,to the roof surface,unless the between the wall and the handrail. roof has a slope steeper than 4 units vertical in 12 units horizontal 10033.3.7 Guardrails.Stairways open on one or both sides shall (33%slope). have guardrails as required by Section 509. 1003.3.3.12 Roof hatches. All )required interior stairways that extend to the top floor in any building four or more stories in 10033.3.8 Alternative stairways. height shall have, at the highest point of the stair shaft, an approved hatch openable to the exterior not less than 16 square 10033.3.8.1 Circular stairways. Circular stairways conform- feet(1.5 m2)in area and having a minimum dimension of 2 feet ing to the requirements of this section may be used as a means of (610 mm). egress component in any occupancy.The minimum width of run shall not be less than 10 inches(254 mm)and the smaller stairway EXCEPTION:A roof hatch need not be provided on pressurized radius shall not be less than twice the width of the stairway. enclosures or on stairways that extend to the roof with an opening onto that roof. 100333.8.2 Winding stairways.In Group R,Division 3 Occu- 1003.3.3.13 Stairway identification. Stairway identification F panties and in private stairways in Group R,Division 1 Occupan- signs shall be located at each floor level in all enclosed stairways F cies,winding stairways may be used if the required width of run is in buildings four or more stories in height.Such signs shall iden- F provided at a point not more than 12 inches(305 mm)from the tify the stairway,indicate whether or not there is roof access,the F side of the stairway where the treads are narrower,but in no case floor level,and the upper and lower terminus of the stairway.The F shall the width of run be less than 6 inches(152 mm)at any point. sign shall be located approximately 5 feet(1524 mm)above the F landing floor in a position that is readily visible when the door is in F 10033.3.8.3 Spiral stairways.In Group R,Division 3 Occupan- either the open or closed position. Signs shall comply with F cies and in private stairways within individual units of Group R, requirements of UBC Standard 10-2. F Division 1 Occupancies,spiral stairways may be installed.A spi- ral stairway is a stairway having a closed circular form in its plan 1003.3.4 Ramps. view with uniform section shaped treads attached to and radiating 1003.3.4.1 General.Ramps used as a component in a means of about a minimum diameter supporting column. Such stairways egress system shall conform to the requirements of Section may be used as a required means of egress component where the 1003.3.4. area served is limited to 400 square feet(37.16 m2). EXCEPTION:Ramped aisles within assembly rooms shall con- The tread shall provide a clear walking area measuring at least form to the requirements in Section 1004.3.2. 26 inches(660 mm)from the outer edge of the supporting column 1003.3.4.2 Width.The width of ramps shall be determined as to the inner edge of the handrail.The effective tread is delineated specified in Section 1003.2.3,but shall not be less than 44 inches by the nosing radius line,the exterior arc(inner edge of railing) and the overlap radius line (nosing radius line of tread above). serving mm),except as specified herein and in Chapter 11.Ramps s Effective tread dimensions are taken along a line perpendicular to servingoccupant load of less than 50 shall not be less than the center line of the tread.A run of at least 71/2 inches(191 mm) 36 inchess(914 mm)in width. shall be provided at a point 12 inches(305 mm)from where the Handrails may project into the required width a distance of tread is the narrowest. The rise shall be sufficient to provide a 31/2 inches(89 mm)from each side of a ramp.Other projections, headroom clearance of not less than 6 feet 6 inches(1981 mm); such as trim and similar decorative features,may project into the however,such rise shall not exceed 91/2 inches(241 mm). required width 11/2 inches(38 mm)from each side. 100333.9 Interior stairway construction. Interior stairways 1003.3.4.3 Slope.The slope of ramps required by Chapter 11 that shall be constructed based on type of construction requirements as are located within an accessible route of travel shall not be steeper specified in Sections 602.4,603.4,604.4,605.4 and 606.4. than 1 unit vertical in 12 units horizontal(8.3%slope).The slope of other ramps shall not be steeper than 1 unit vertical in 8 units Except where enclosed usable space under stairs is prohibited horizontal(12.5%slope). by Section 1005.3.3.6,the walls and soffits of such enclosed space shall be protected on the enclosed side as required for one-hour 1003.3.4.4 Landings.Ramps having slopes steeper than 1 unit fire-resistive construction. vertical in 20 units horizontal(5%slope)shall have landings at the Stairways exiting directly to the exterior of a building four or top and bottom,and at least one intermediate landing shall be pro- more stories in height shall be provided with a means for emer- vided for each 5 feet(1524 mm)of vertical rise measured between gency entry for fire department access.(See the Fire Code.) the horizontal planes of adjacent landings.Top landings and inter- mediate landings shall have a dimension measured in the direction 1003.3.3.10 Protection of exterior wall openings.All openings of ramp run of not less than 5 feet(1524 mm).Landings at the bot- in the exterior wall below and within 10 feet(3048 mm),measured tom of ramps shall have a dimension in the direction of ramp run of horizontally, of openings in an interior exit stairway serving a not less than 6 feet(1829 mm). building over two.stories in height or a floor level having such Doors in any position shall not reduce the minimum dimension openings in two or more floors below,shall be protected by fixed of the landing to less than 42 inches (1067 mm) and shall not or self-closing fire assemblies having a three-fourths-hour fire- reduce the required width by more than 7 inches(178 mm)when protection rating.See Section 1006.3.3.1. fully open. 1-110