UL SUBJECT 2752-2011 OUTLINE OF INVESTIGATION FOR FABRICATED STAIRWAYS (Issue Number 1)《预制楼梯的调查大纲 (议题编号 1)》.pdf

1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULMay 26, 20111SUBJECT 2752OUTLINE OF INVESTIGATIONFORFABRICATED STAIRWAYSIssue Number: 1May 26, 2011COPYRIGHT 2011 UNDERWRITERS LABORATORIES INC.UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER

2、REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULMAY 26, 2011SUBJECT 27522No Text on This PageUL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULCONTENTSINTRODUCTION1 Scope .42 General 42.1 Components .42.2 Units of measurement .52.3 Undated

3、 references .53 Glossary .5CONSTRUCTION4 General 55 Materials and Assembly .56 Protection Against Corrosion .6PERFORMANCE7 Bending Test 68 Step Bending Test 69 Tread-to-Stringers Shear Strength Test 710 Stair-Rail-Strength Test .711 Slip Resistance Test .7MARKING12 Permanence 713 Details 814 Caution

4、ary .8INSTRUCTION15 General .9MAY 26, 2011 SUBJECT 2752 3UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULINTRODUCTION1 Scope1.1 These requirements cover fabricated stairways used temporarily during construction.1.2 These requirements do not co

5、ver:a) Construction or installation of fabricated stairways;b) Landings or platforms; orc) Spiral stairways.2 General2.1 Components2.1.1 Except as indicated in 2.1.2, a component of a product covered by this standard shall comply withthe requirements for that component.2.1.2 A component is not requi

6、red to comply with a specific requirement that:a) Involves a feature or characteristic not required in the application of the component in theproduct covered by this standard, orb) Is superseded by a requirement in this standard.2.1.3 A component shall be used in accordance with its rating establish

7、ed for the intended conditions ofuse.2.1.4 Specific components are incomplete in construction features or restricted in performancecapabilities. Such components are intended for use only under limited conditions, such as certaintemperatures not exceeding specified limits, and shall be used only unde

8、r those specific conditions.MAY 26, 2011SUBJECT 27524UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL2.2 Units of measurement2.2.1 When a value for measurement is followed by a value in other units in parentheses, the secondvalue may be only a

9、pproximate. The first stated value is the requirement.2.3 Undated references2.3.1 Any undated reference to a code or standard appearing in the requirements of this standard shallbe interpreted as referring to the latest edition of that code or standard.3 Glossary3.1 For the purposes of this standard

10、, the following definitions apply.3.2 STAIR RAIL A rail that is designed to be grasped by the hand so as to provide stability orsupport.3.3 TEST FAILURE Visible weakening of the test unit or component or other damage in which thestructure or component is buckled, twisted, sheared, torn, or fractured

11、 as a result of the test.CONSTRUCTION4 General4.1 A product shall be constructed so that it will have the strength and durability to withstand normalusage and to comply with the performance requirements.4.2 An exposed metal surface shall be free from sharp edges, burrs, and other features that const

12、itute arisk of injury to persons.4.3 All welds shall be free from undercuts, cracks, and closely spaced in-line surface porosity.5 Materials and Assembly5.1 All metal parts and fittings shall be made of aluminum or steel alloys, wrought iron, malleable iron, orother metal that is of equivalent stren

13、gth for the intended purpose and shall be securely attached bymeans of rivets, bolts, screws, or other means determined to be the equivalent.5.2 Nuts shall be lock nuts or they shall be used with lock washers.5.3 Metal decking shall be corrugated, serrated, knurled, dimpled, grated, or coated with s

14、lip-resistantmaterial.5.4 The top edges of stair rail systems used as handrails shall not be more than 37 inches (94 cm) highnor less than 30 inches (76 cm) from the upper surface of the stair rail system to the surface of the tread.MAY 26, 2011 SUBJECT 2752 5UL COPYRIGHTED MATERIAL NOT AUTHORIZED F

15、OR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL6 Protection Against Corrosion6.1 All hardware and materials shall be of a grade or alloy known to be resistant to atmospheric corrosionor shall be additionally protected against corrosion.6.2 Metal shall not be used in combinations su

16、ch as to cause galvanic action that will adversely affect thestrength of the product.PERFORMANCE7 Bending Test7.1 A product shall withstand, without failure or visible damage to the structure, a load equal to 1.67 timeswidth (ft) times length (ft) times load rating (100 psf minimum). The length used

17、 in calculating the totalload would be the total run which can be calculated by the maximum total rise x step run divided by thestep rise.7.2 The product is to be installed in accordance with the manufacturers instructions.7.3 The load is then to be distributed equally across all the treads.8 Step B

18、ending Test8.1 The strength of the tread shall be tested by applying a 1,000 lb load for a period of at least one (1)minute over a block of wood2x4(1-1/2 inches by 3-1/2 inches) cut to a length the same as the depthof the tread being tested.8.2 The wood block shall be located at the center of the tr

19、ead between the stringers.8.3 This test shall be performed on each tread of a different design, length or support. The test shall alsobe performed on any tread with different material specification.8.4 The tread shall withstand the load without test failure. Permanent deformation (set) up to 1/100 i

20、nchis permissible.MAY 26, 2011SUBJECT 27526UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL9 Tread-to-Stringers Shear Strength Test9.1 The strength of the tread attached to the stringer shall be tested by applying a 1,200 lb load for aperiod o

21、f at least one (1) minute over a block of wood2x4(1-1/2 inches by 3-1/2 inches) cut to a lengththe same as the depth of the tread being tested.9.2 The wood block shall be located on the tread against the edge of one of the stringers.9.3 This test shall be performed on each tread of a different desig

22、n, length or support. The test shall alsobe performed on any tread with different material specification.9.4 On removing the load, the unit shall show no indication of test failure either in the fastening meansattaching the tread or on the stringer.10 Stair-Rail-Strength Test10.1 A stair rail, as me

23、ntioned in 5.4, and its supporting means shall support without failure or visibledamage a load of 200 pounds (91 kg) between the greatest unsupported distance of the uprights whichsecure the stair rail to the stairway when tested as described in 10.2.10.2 The stair rail assembly strength is to be de

24、termined with the rails secured to the stairs as intendedin service. The test load is to be applied in the vertical and then in the horizontal plane.11 Slip Resistance Test11.1 The tests were conducted in accordance with the Standard for Slip Resistance of Floor SurfaceMaterials, UL 410.MARKING12 Pe

25、rmanence12.1 A required marking shall be legible and permanent.12.2 A required marking shall be molded, die-stamped, paint-stenciled, stamped or etched metal that ispermanently secured, or indelibly stamped lettering on a pressure-sensitive label secured by adhesivethat, upon investigation, is found

26、 to be acceptable for the application. Ordinary usage, handling, storage,and the like, of a product are considered in the determination of the permanence of a marking.12.3 Unless it has been investigated and found to be acceptable for the application, a pressure-sensitivelabel or a label that is sec

27、ured by cement or adhesive and that is required to be permanent shall complywith the requirements in the Standard for Marking and Labeling Systems, UL 969.MAY 26, 2011 SUBJECT 2752 7UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL13 Details13.

28、1 A product shall be legibly and permanently marked with the manufacturers name, trade name, ortrademark; the date or other dating period of manufacture not exceeding any three consecutive months;a distinctive catalog or model number or that which has been determined to be the equivalent; and therat

29、ed working load. If a manufacturer produces products at more than one factory, each product shall havea distinctive marking to identify it as the product of a particular factory.Each product or unit shall be clearly marked to indicate possible combinations and the load rating for eachof these combin

30、ations.Exception No. 1: The manufacturers identification may be in a traceable code if the product is identifiedby the brand or trademark owned by a private labeler.Exception No. 2: The date of manufacture may be abbreviated or in a nationally used conventional code,or in a code affirmed by the manu

31、facturer provided:a) The date code does not repeat in less than 20 years.b) The date code does not require reference to the manufacturers records to determine whenthe product was manufactured.13.2 If a manufacturer produces products at more than one factory, each product shall have a distinctivemark

32、ing to identify it as the product of a particular factory.14 Cautionary14.1 Each product fabricated with continuous metallic members shall be marked with both of the followingor statements determined to be the equivalent, each preceded by the word Caution:Risk of electric shock. Metal stairway devic

33、es should not be used where contact may be madewith electrical circuits. Refer to Instruction Label.Risk of injury. Acids and other corrosive substances may severely affect the strength of metalstairway devices. Use extreme care around such materials and follow instructions.14.2 The cautionary marki

34、ngs shall be in legible letters not less than 1/8 inch (3.2 mm) high.MAY 26, 2011SUBJECT 27528UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULINSTRUCTION15 General15.1 A product shall be marked with legible instructions covering its intended u

35、se.15.2 The instructions shall contain only information that applies to the specific type of product and shallinclude those items in the following list that are applicable to the product.a) Before and after using, check all parts for proper function and damage to component parts.Do not use a damaged

36、 or improperly functioning stairway.b) Any parts that have been exposed to excessive heat, as in the case of fire, should beimmediately removed from service and destroyed due to loss of structural strength.c) Do not permit oil, grease, or slippery material to accumulate on climbing or grippingsurfac

37、es.d) Do not use the product if the surface is damaged or has deteriorated.e) Stairways are designed with rated working loads of (fill in the blank) pounds or pounds persquare foot (fill in the blank) kg or kg/m2. The total combined weight of each worker and allmaterials should not exceed the rated

38、working load. Do not overload.f) Do not apply impact loads to any parts.g) Do not use acids or other corrosive substances on a plank or platform without consulting theplank or platform manufacturer for specific instructions.h) Stairways shall not be allowed to contact unprotected, energized electric

39、al lines orequipment. Maintain a minimum safe distance of at least 10 ft. (3 m). Consult the powercompany to shut off power or insulate/relocate the line if working closer than 10 ft. DANGER! To avoid contact and shock hazard, stairways shall not be used in the vicinity of energizedpower lines or electrical lines.i) Before using, refer to manufacturers instructions.MAY 26, 2011 SUBJECT 2752 9UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULMAY 26, 2011SUBJECT 275210No Text on This Page