4571

( Reaffirmed 1995) IS : 4571 - 1977 Indian Standard SPECJFICATION FOR ALUMINWM EXTENSION LADDERS FOR FIRE BRIGADE USE (First Revision ) Fire Chairman Srrt:~~P. N. MEHROTRA Ministry Fighting Sectional Committee, Re@senting of Home Affairs BDC 22 Members SIII:I M:\HE3Ii C. ACRAWAL Brijbasi Udyog, Mathura ( UP ) Snr+r P. S. 11~~13nJE.e ( Alternate ) Assr~r.4~~ SECUIZITY ~O~PICFIL Railway Board ( Ministry of Railways ) ( FIRE ), NORTHERN RAILWAY Central Building Research Institute ( CSIR ), Dx G. N. BADABII Roorkee SHRI GOPAL KRJSHAN ( Alternate ) Bokaro Steel Limited, Rokaro Steel City Srrru S. R. I&bNS>\L Tariff Advisory Committee, Bombay %ltr P. K. BJIA~UCIIA SHKI A. CHATTERJI ( Alternatc ) Saltr S. C. CI:ATTEJ~JEE West Bengal Fire Services, Calcutta Srrtx 1~. K. baNr$RJXE ( Alternate ) Hindustan Steel Limited, Ranchi SHRI K. D~n~~rtov SH I&IC. 13. SX\I~XA ( Alternate ) Bhabha Atomic Research Centre, Trombay, Bombay SIIEI R. R. DII~BLEY Home ( Police ) Department, DII~I:C~OI~, FIRE SERVICE Government of Andhra Pradesh, Hyderabad Ministry of Dcfence ( R & D ) SHRI I’. N. Gnosn Sultl A. N. ~‘~J-~LUWALI.~&lern&! ) ( SXILI G. N. G1nm.4~1 Directorate General of Supplies & Disposals, New Delhi SHRI 3%. C. VEHMA ( Alterrzate ) Srir<r D. P. Gur~a Directorate General of Technical Development, New Delhi Da D. S. JAISWAR Avon Services ( P & A ) Pvt Ltd, Bombay SHILI H. M. SAH~DRA ( Alternate ) Sri~x J. S. JAJISEIE:UJI Steclage Industries I,imited ( Minimax Division ), Calcutta SWXI 1-I. K. EIEANI ( Alternate ) ( Continued on page 2 ) @ Cqtyright STANDARDS 1978 INSTITUTION INDIAN This publication is protected under the Indian CobJvight Act ( XIV of 1957) and reproduction in whole or m part by any means except with written permission of the publisher shall be deemed to be an infringement of copyright under the said Act_ lS:4571-1977 (Continued from page 1 ) Refwenting Fire & Safety Appliances Co, Calcutta ol Members SHRI S. N. KZYDU SHILI SHRI s. PAUL ( 13. R. MEHTA Ak?rnate ) SHRI 11. MEIITA MAJ S. K. MISRA SHR~ 2). K. MAJUMI~ER SHRI A. I(. SARKAR ( .&mate ) Directorate General of Civil Aviation, New Delhi SHRI H. C. R~\I CROUDHURY Home Department ( Fire Service ), Government of SHRI I. RA’L’IIINASAMI Tamil Nadu, Madras Municipal Corporation of Greater Bombay ( Bombay SHRI G. S. SALVI Fire~Brigade ), Bombay Oil & Natural Gas Commission, Dehra Dun SZIRI P. L. S~BASTIN SHRI V. V. KrnfMATKAR ( Alternate ) Kooverji Devshi & Co Pvt Ltd, Bombay SHRI P. H. SETHNA SHIEI N. T. PANJWANI ( Alternate ) Newage Industries, Surendranagar SHKI J. V. SHAH SHRI B. J. SHAH ( Alternate ) DGL Private Limited, New Delhi SHRI SJARUN SHARXA SHRI T. R. BHANOT ( Alternate ) Synthetics & Chemicals Limited, Bareilly SHRI D. K. SIRXAR Municipal Corporation of Delhi ( Delhi Fire SKRIR. S. SUNDARAM Service ), Delhi Sur Enamel & Stamping Works Private Limited, SHRI TaRIT SUR Calcutta SHRI S. SUR ( Alternate ) ’ Heavy Engineering Corporation Ltd, Ranchi SHRI N. P. VERGHESE Urban Development, Public Health and Housing SHRI B. V. WAGLE Department, Government of Maharashtra, Bombay SHRI V. H. MADKAIEAR ( Alternate ) Director General, ISI ( Ex-o&%io Member ) SHRI D. AJITHA SI~HA, Director ( Civ Engg ) Secretary SHRI K. M. MATHUR Deputy Director ( Civ Engg ), ISI Central Industrial Security Force ( Ministry Home Affairs ), New Delhi Air Foam Industries Private Ltd, New Delhi Ministry of Defence ( DGI ) Allen Richards & Co, Calcutta Fire Convener SHRI P. N. GHOSH Fighting Units Subcommittee, BDC 22 : 3 Ministry of Defence ( R & D ) LT-COL M. N. MENON ( Alternate to Shri P. N. Ghosh ) Premier Automobiles SERI G. Y. BIIATT SIIRI M. L. MAHAJAN ( Alternate ) Ltd, Bombay ( Continued on page 7 ) 2 IS :4571-1977 Indian Standard SPEClFICATION FOR ALUMINKJM EXTENSION LADDERS FOR FIR-E BRIGADE USE ( First Revision ) 0. 0.1This FOREWORD Indian Standard ( First Revision ) was adopted by the Indian Standards Institution on 30 November 1977, after the draft finalized by the Fire Fighting Sectional Committee had been approved by the Civil Engineering Division Council. 0.2 Wooden extension ladders for fire fighting purposes have already been covered in IS : 930-1977*. During the course of working to this standard, it has been felt that timber ladders being difficult to handle because of their heavy mass, often present difficulties to the fire fighting personnel at the time of fire fighting. Aluminium ladders being lighter are now being preferred to timber ladders by the fire fighting personnel. This standard was published in 1968. Based on the indigenous availability of aluminium section this revision has been prepared, the principal modification being relaxation in regard to the deflection. 0.2.1 The aluminium extension ladder consist of one main and one extending section. The -design shall be such as to ensure easy sliding of the extending section without excessive clearance in the guide and over extension of the ladder. The extending section shall be guided throughout the full range of extension in a manner such that the sections cannot separate, retaining clips being on the main section. If so required, an operating gear is fixed to facilitate removal of the extending section for separate use. 0.3 For the purpose of deciding whether a particular requirement of this standard is complied with, the final value, observed or calculated, expressing the result of a test or analysis, shall be rounded off in accordance with IS : ‘Z-19607. The number of significant places retained in the rounded off value should be the same as that of the specified value in this standard. *Specification tRulcs for wooden extension ladder for firE fighting for rounding off numerical values ( revised ). purposes ( jirst revision ). 3 IS : 4571 - 1977 1. SCOPE 1.1 This standard lays down mass and performance tests fighting purposes. 2. GENERAL 2.1 Ladder -- The width of the extending section inside its strings shall be not less than 30 cm. The rounds shall be with non-slip serrations running the full length. These shall be fixed by expanding and flaring and shall be spaced at 25 cm centre to centre. 2.2 Safety Device - The heals of the stiles or strings of lower section shall be fitted with rubber feet. The pawls shall be bolted to stiles or strings and their action shall be such that they are set for engagement until they have been rested on a round, and trip to clear immediately the ladder is extended. 3. MATERIAL 3.1 The aluminium alloy section for stiles or strings shall conform Grade HE-20 ( in WP temper ) of IS : 3921-1966* or IS : 733-1975t. 3.2 The conform aluminium alloy section used for the rounds of the ladder to Grade HV ( in W temper ) of IS : 1285-19751. to the requirements regarding material, size, of aluminium extension ladders for fire shall 3.3 Aluminium alloy latch conforming to IS Designation ~~t~;~ber feet shall be produced from aluminium alloy A-6 of IS : 617-19759 by chill casting. ladder shall have shear hardness of of aluminium 4. SXZE be in the three sizes, 4.1 Extension ladders when fully extended shall namely, 4.5 m, 7.5 m and LO.5 m ( see Fig. 1 ). *Specification for aluminium channels. j-specification for wroushr aluminium and aluminium alloy, bars rods and .sections ( for general en$nrering purposes ) ( second revision). $Specificatlon for wrought aluminium and aluminium alloys, extruded round tube and hollow sections ( for general engineering purposes ) Csecond r&-ion ). @pecification for aluminium and aluminium engineering purposes ( second reoision ). alloy ingots and castings for general 4 IS :4571-1977 5. MASS 5.1 The ladders exceed as given shall be as light below: 4.5 10.5 6. TEST m m 7.5 m as possible, their total mass shall not 20 kg 30 kg 48 kg REQUIREMENTS 6.1 Deflection - The fully extended ladder shall be placed across trestles, positioned 90 cm from each end. On a 30 cm wide board placed across the strings at the centre of the span, a load of 373 N ( 38 kgf) shall be applied, allowed to remain there for a period of not less than 1 minute and then removed. A load of 736 N ( 75 kgf) shall then be gradually applied and the deflection due to this load shall not exceed 30 cm measured from the original position. The load shall then be gradually increased to 1 128 N ( 115 kgf ) and the additional deflection shall not exceed 50 percent of the deflection obtained with the 736 N ( 75 kgf ). There shall be no sign of distress. 6.2 Strength of Round 6.2.1 With the feet of the ladder at a distance of 2.5 m in the case of 10*5m, 1.75 m in the case of 7.5m, and 1.25 m in the case of 4’5m ladder from wall, the ladder shall be fully extended and its head rested against the wall. A load of 320 kgf shall then be gradually applied to the middle of at least one round in each section by means of a metal hook having a bearing surface 5 cm wide and suitably lined to prevent bruising of the round. No sign of failure shall be apparent either in the round or at its junction with the strings. 6.2.2 The fully extended ladder shall be placed vertically and a man weighing approximately 75 kg shall jump on each round from the round immediately above, No sign of failure shall be apparent either in the round or at its junction with the strings during this test. 6.2.3 trestles. rounds. junction The fully extended ladder shall be placed horizontally across One man weighing approximately 75 kg shall walk over the No sign of failure shall be apparent either in the round or at its with the strings during this test. a wall with feet of the ladder the wall in the case of 4.5 m, and two men are ascending the while descending the ladders, it 6.3 Sway - When pitched against 1.25 m, 1.75 m and 2.5 m away from 7.5 m and 10.5 m ladders respectively ladder or one man carrying another shall not sway. IS : 4571 - 1977 6.4 Extension - The ladder shall be capable of being extended by one man by means of rope [ manila 45 mm in circumference (see IS : 1084The 1969” )] over a pulley on the main section to the required length. ladder shall also be not over extended. 7. MARKING 7.1 Each extension the following ladder information: shall be clearly or trade-mark, and and permanently if any; marked with a) Manufacturer’s c) Year name b) The size of the ladder; of manufacture. ladder 7.1.1 The extension tion Mark. may also be marked with the ISI Certifica- NOTE - The use of the IS1 Certification Mark is governed by the provisions of the Indian Standards Institution ( Certification Marks ) Act and the Rules and Regulations made thereunder. The IS1 Mark on products covered by an Indian Standard conveys the assurance that they have been produced to comply with the requirements of that standard under a well-defined system of inspection, testing and quality control which is devised and supervised by ISI and operated by the producer. IS1 marked products arc also continuously checked by ISI for conformity Details of conditions under which a licence to that standard as a further safeguard. for the use of the IS1 Certification Mark may be granted to manufacturers or processors, may be obtained from the Indian Standards Institution. 8. SAMPLING 8.1 Each ladder in this standard. AND CRITERIA FOR CONFORMITY for the various requirements specified shall be checked *Specilication for manila ropes ( second revision ). 6 IS:4571 - 1977 ( Conrinued from page 2 Members CEATTERJEE ) Representing SHRI G. N. GIDWANI SHRI H. C. VEIIXA ( Alternate CDIc J. M. KAUSHAL ) SIIRI s. c. Bengal Fire Services, Directorate General of New Delhi West Calcutta Supplies & Disposals, \,.G SIIRI R. B. MOEINDR~ SHRI P. N. MHHI<OTRA SHRI A. G. NARSAPUR ( Alternate Directorate of Maintenance, Plans & Inspection ( Ministrv of Defence I , New Delhi 1. ) New Delhi SHRI S. V. PARAIIKAR ( Alternate ) Directorate General of Civil Aviation, New Delhi SHRI H. C. RAI CHOUDHUEY Bombay Greater Municipal Corporation of SHRI G. S. SALVI ( Bombay Fire Brigade ), Bombay Ministry of Defence ( DGI ) DR A. K. SEN Kooverji Devshi & Co Pvt Ltd, Bombay SHRI P. H. SETHNA SHeI N. T. PANJWANI ( Alternate ) Synthetics & Chemicals Ltd, Bareilly SHRI D. K. SIIZKAR of Delhi ( Delhi Fire Municipal Corporation SHRI R.S. SUNDARAM Service ), Delhi Urban Development Public Health, Housing DepartSHRI B. V. WAGLE ment ( Government of Maharashtra ), Bombay SHRI V. H. MADKAIKAR ( Altemata ) Ministry of Home Affairs Kirloskar Brothers Limited, ’ IS :4571-1977 INfERNATIONAL Base Units Quantity Length Mass Time Electric current Thermodynamic temperature Luminous Amount intensity of substance Units Unit radian steradlan Symbol rad Sr SYSTEM OF UNITS ( SI U-NITS) Unit mecre kilogram second ampere kelvin candela mole Symbol m kg S A K CO m0l Supplementary Quantity Plane Solid angle angle Units Derived Quantity Force Energy Power Flux Flux Unrr newton loule watt weber Symbol I I” W Wb T HZ s Pa 1 Canversion N = 0.101 972 kgf J= Wb = I N.m I V,s I I I w = I J/s T = density conductance stress tesla hertz siemens Pascal Frequency Electric Pressure, I Wb/m2 I +I2 = I c/s ( s-1 ) I S=IA/V I Pa - I N/m” 8 AMBN~WIENT NO. I TO MAR&I 1971) IS : 4571-L-1977 SPECIFICATION FOR ALUMINIUM EXTENSION LADDERS FOR FIRE BRIGADE USE ( First Revision ) Addendum ( Page 4, clause 4.1 ) Add the figure given on page 2 after 4.1: All dimensions FIG. 1 TYPICAL in millimetrcs. SKETCX OF 7.5 m EXTENSIONLADDER 2 Printrd NewIndia at Printing ( l3DC 22 ) Press, Ehurja, India AMENDMENT ND. 2 TO SEPTEMBER 1981 IS :4571-1977 SPECIFICATION fOR ALUMINIUM EXTENSION LADDERS FOR FIRE BRIGADE USE (FiZ'St RevSsionl Alterations _----(Pa98 4, ctmtee 3.2) - Substitute the following for the existing clause: '3.2 The aluminium allay section used for the rounds of the ladder shall conform to Grade HV-20(in W or UP temper) of 1S:l.Z85-1975~.' (Page 6, ctiuee 6.4, first sentence) - Substitute the following for the existing sentence: 'The ladder shall be capable of being extended by one man by means of rope of breaking strength not less than 10 000 kgf.' (BDC 22) Reprography Unit, ISI, New Delhi, India L AMENDMENT NO. 4 TO OCTOBER 1984 ., IS:4571-1977 SPECIFICATION FOR ALUMI!fIUM EXTENSIO'1 '7 LADDERS. FOR FIRE 8RIGADE USE . fFi.rat Reviaionl d--_ Corri aendum -6, c&use *Amenbent No. 2)] '10 000 kgf'. (B3C 22) Repro&rwhy Unit, ISI, Aew Delhi, India [fige 6.4, first sentence (in SuSst?tute '1 OOC kgf' for AMENDMENT NO. 5 FEBRUARY -TO 1989 FOR FOR FIRE IS : 4571- 1977 SPECIFICATION ALUMINIUM EXTENSION LADDERS BRIGADE USE ( First Revision ) [ Page 4, clause 3.1 ( see also Amendment No. 3) ] - Substitute ‘IS : 733-1983t’for ‘IS : 733-1975-t’. [ Page 4, clause 3.2 ( see also Amendments No. 2 and 3 ) ] - Substitute ‘IS : 733-1983.f’fou ‘IS : 733-19751’. ( Page 4, foot-note marked with ‘I’ mark ) - Substitute the following for the existing foot-note: alloy, ‘tSpecitication for wrought aluminium and aluminium sections ( for general engineering purposes ) ( third revision).’ bars rods and ( Page 5, clause 6.1, ‘1 128 N ( 115 kgf )‘. ( Page 6, foot-note ) (BDC22) line 8 ) Delete. _-I__ Substitute ‘1098 N ( 112 kgf )'for Printed at Swatantra Bharat Pre,r, Delhmlndia