Rail ladder. A fixed ladder consisting of side rails joined at regular intervals by rungs and fastened full length or 4. Each section of ladder shall be horizontally offset the platforms; and for other live loads as indicated in from adjacent sections with sufficient clearances. A lancting platform shall be provided for safe 4. The weight of the ladder and attached the user See Fig. The weight of the platforms and feet See Fig.
Steel ladders and 4. AISC shall be designed to meet the load requirements Portable steel ladders may be adapted for described in 4. Live loads 4. Higher strength steel may be used, subject to the a.
Each step or rung in the 4. The number and position of additional concentrat- 4. Aluminum ladders sidered in the design. The following live loads I - Portable aluminum ladders may be adapted shall be considered in the design, where applicable: for use as fixed ladders provided they meet all the a.
A uniform coating of ice on all parts of the ladder; requirements of this standard and all live loads. A wind load on all parts of the ladder; 4. Alloys or of appropriate temper as defined by ADM 1 - shall be used.
The weight of rigging attached to the ladder, Other aluminum alloys may be used subject to the including the load to be lifted; and requirements of ADM 1 - Anticipated impact loads resulting from the use of 4. Welding for aluminum ladders ladder safety systems and other live loads. All live loads shall ADM Ail platforms shall be A American National Standard A The design loads shall be as specified in 4. The minimum size cross section requirements of steps and rungs specified in 5.
The minimum clear width between side rails at section properties adequate to support the design any point shall not be less that 16 inches, and side loads specified in 4. Fastenings meeting the design load requirements b. For additional load concentrations or attachment shall be used for the permanent attachment of of ladder safety systems, and for clear widths wood ladders to structures, building, or equipment.
In no case shall the minimum size cross section Wood Construction. Materials other than s teel, com- in 5. The size cross section of steps and rungs shall be the specific materials listed , aluminum, and wood may uniform in the san1e length of climb. Steps and rungs shall be parallel and level. The minimum sizes cross sections of steps and rungs fabricated of steel 4. All newly installed fixed ladders shall equivalent in strength for square, rectangular, be stamped, marked or welded with the manufacturer or other solid shapes is required.
For ladders subject to unusually corrosive with a permanent legible marking that will stand up to atmospheric exposures, l-inch-diameter solid environmental conditions. The minimum size of 5. Design Details for aluminum structural components shall be determined Fixed Ladders in accordance with the provisions of ADM 1 - In cases where the ladders are subjected to corrosive atmospheric exposure or placed in contact with 5.
The minimum at the access level. All vertical spacing of the rungs from cross section as specified in 5. The minimum inside clear width of step other metal s used. The minimum cross section of width shall be uniform in the same length of climb wooden steps and rungs shall be as specified in ANSI See Fig. The following are general requirements 5.
The same size cross section side rails shall be or rung to the side rails. The connection of the rungs maintained for all ladders in the same length to the side rails shall be designed to develop the full of climb. For welded 5. For ladders subject to unusual atmospheric 5. Rung ends shall be in accor- accordance with requirements of ADM 1 - The minimum size of side rails for wood ladders shall be as required in ANSI 5. The minimum 5.
Irregular allowable units stress for the type and shape of other shapes that do not provide for uniform power metal s used. Splices shall for all ladders in the same length of climb. The minimum size cross section of side rails in the side rails. The spacing of supports for specified in 5.
Variations in size cross section fastening the side rails to the structure, building, or shall be permitted provided the section properties equipment shall be 10 feet 0 inches for the size of side are adequate to support the design loads and are rails recommended in 5.
For additional b. For additio nal load concentratio ns or attachment of design loads or attachment of ladder safety systems, ladder safety systems, and for spacing of supports or for variations in size cross section of side rails, that exceeds the maximum spacing recommended, the spacing of supports shall be adjusted in accordance Lht maximum size of side rails shall be increased with recognized design practice see, e.
G in accordance with recognized design practice. The maximum spacing of supports opening is fitted with a deflector plate See Fig. The springs or for steel in 5. The top rung of the ladder may also be located be low the top of the hatch to provide required 5.
The top of a step or rung of a clearance for the hatch cover See Fig. Grab Bars or other such items that can be grasped by the climber.
For a parapet ladder, 5. In the case of the unusual hatch conditions, the clearance on the climbing 5. Lightning protection, bo nding and grounding of metal of the cage. This will give a maximum spacing, center to center, approximately inches See Fig. NFPA - The bottom of the cage shaH be flared not less than 5. Where practical difficulties are encountered, cages 5. An example of cage construction is shown in Fig.
The inside of the cage shall be clear of projections. For variations in size cross section and spacing or rung. The inside clear width of the well shall be a of vertical bars, the maximum spacing of horizontal nominal 30 inches for rectangular wells See Fig.
If an 6. The total depth of the platform shall active fall protection system is used, a suitable anchorage provide a minimum space of 30 inches from the center- point for connection of the faJI protection system must line of the ladder on the climbing side.
The width of the be provided. The the designed static load. Ladder Safety System 7. The maximum length of movement of carriers or cable guides fo r flexible carriers. When tested in the centerline of the carrier and the point of attachment accordance with 7. The test weight must not strike the ground. This 7. Note: dance with the manufacturer's recorrunendations. Test Ladder: The test ladder shall be fabricated of 25 feet and a maximum spacing of 40 feet along the using steel and be constructed in accordance with entire length of the carrier.
Quick Release Mechanism: The test weight or test the user's center of gravity. The harness shall meet the torso, whichever is applicable, shall be released by requirements of ANSI Z The safety sleeve 7. Position the safety sleeve on the carrier sufficiently above ground level. Connect one end manufacturer's instructions included with the equipment of the test lanyard to the safety sleeve at the point that is at time of shipment from the manufacturer, proper size norn1ally connected to the harness.
Connect the second and type s of carrier s intended to be used with the end of the test lanyard to the rigid pound test weight. Release the test weight from a point within indicate the direction of use of the safety sleeve on the 12 inches horizontally from the centerline of the carrier. The ladder safety system shall be marked with Evaluate the system in accordance with 7.
Position the safety sleeve on the allowed on the system, warnings against unauthorized carrier a convenient height above ground level. Apply a alteration of substitution of system elements and compo- static load of pounds to the sleeve in the downward nents, warnings against use of system with incompatible direction. Maintain the load for a period of 5 minutes. Evaluate the system in accordance with 7. Note: a clamp or stop may be positioned below the sleeve to 7.
Ladder safety systems utilizing other designs shall meet 7. Install the ladder safety system onto the test ladder, as it would be in service. Position the safety sleeve on the carrier at least 6 feet above ground level. Fit the harness to the test 7. Test Lanyard: The test lanyard used in performing normal use. Release the test diameter aircraft cable.
The lanyard shall be tenui- nating at each end by forming a flemish eye over a ' The conunittee concludes that outward backward fall risk potential is thimble and suitable connector secured with swaged critical. However no scientific determination on this issue is currently fitting. When measured under a tension of 10 available at the time of this standard revision. The committee will mo. A committee will be appointed bearing point to bearing point between connectors. This 9. The current test tribute significantly to safety.
Haste, sudden movements, does Naf cover outward backward falls. See footnote 7. The footwear employed by the user may also contribute to 8. Protective Finishes falls.
Improper climbing posture creating user clumsiness on the ladder may also cause falls. Edward E. Cooke W. Pritsky Ait Robert I. Werner Ait. Robert H. David P. JVinger Thomas E. Murray Ait.
Henry W. Buschman, JI James B. Dorenbusch Alt. Robert Sample Arthur L. Schmuhi Ait. Paul V. Robert Reid. David C. Norman J. Markey Ait. Gary Redman. American Ladder Institute. Associated General Contractors of America, Inc. Association of American Railroads. Canadian Standards Association. Edison Electric Institute. Related Standards. General Design Criteria.
Design Details for Fixed Ladders. Design Details for Cages. See Full Reader. Post on Oct 6. Category: Documents download. Tags: information normal atmospheric allowable nearest permanent additional recognized international national design.
Gary Redman Edison Electric Institute Electronic Industries Association
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