1659 Block Boards

7/27/2019 1659 Block Boards

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LIS 166d : 1890

I ndian St andard

BLOCKBOARDS -SPECIFICATION

( hi rd Revi si on

First Reprint October, 1993( Incorporating Amendments No. 1 and 2 1

UDC 674 - 419.33

0 BIS 1993

BUREAU OF INDIAN STANDARDSMANAK BHAVAN, 9 BAHADUR SHAH ZAFAR MARG

NEW DELHI 110002

( Reaffirmed 1996 )


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Wood Products Sectional Committee, CED 20

FOREWORD

This Indian Standard ( Third Revision ) was adopted by the Bureau of19 March 1990, after the draft finalized by the Wood Products Sectionalapproved by the Civil Engineering Division Council.

Indian Standards onCommittee had been

Blockboards are being used in increasing quantities in the construction of railway carriage, bus bodies,marine and river crafts and for furniture making, partitions, panelling, prefabricated houses, etc. Thisstandard was originally formulated in 1960 and subsequently revised in 1969 and 1979 to lay down themethod of manufacture and tests for such boards with a view to assuring the optimum performancerequirements for different uses. The third revision is based on the experience gained in the manufac-ture and the use of blockboards over the years and the modifications mainly relate to the manufactureof cores and review of species of timber. Due to depleting resources of timber, species specified in thisrevision are made recommendatory.

In the formulation of this standard, due weightage has been given to internatronal co-ordination amongstandards and practices prevailing in different countries in addition to relating it to the practices in thefield in this country.

For the purpose of deciding whether a particular requirement of this standard is complied with, thefinal value, observed or calculated, expressing the result of a test or analysis, shall be rounded offin accordance with IS 2 : 1960 Rules for rounding off numerical values ( revi sed ) . The number ofsignificant places retained in the rounded off value should be the same as that of the specified value inthis standard.


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I S 1659: 1990

I ndian St andard

BLOCKBOARDS - SPECIFICATION

( Thi rd Rev i si on )1 SCOPE

1.1 This standard covers the essential require-ments of commercial and decorative blockboardsmeant for interior and exterior uses.

2 REFERENCES

2.1 The Indian Standards listed in Annex A arenecessary adjuncts to this standard.

3 TERMINOLOGY

3.0 For the purpose of this standard, the defini-tions given in IS 707 : 1976 and the following

shall apply.3.1 Blockboard

Blockboard is a having a core made ofstrips wood, not 30 mm inwidth may may not glued

the core glued between or more outerwith direction of grains the

blocks running right angles to the ofgrains the adjacent veneers.

4 GRADES AND TYPES

4.1 Blockboards shall be of the following twogrades:

a) Grade 1Exterior grade of blockboard which ismeant for bus bodies, railway coaches,prefabricated houses, etc, where it is likelyto be exposed to high humidity.

b) Grade 2Interior grade of blockboard which ismeant for furniture, partition, panelling,ceiling, etc.

4.2 Each of the grades specified in 4.1 shall beof the following two types:

a)

b)

Type 1 Blockboards, Decorat iv e Type

These are blockboards with decorative

face veneers on one or both sides for usein high class furniture, panelling, interiordecoration, partitions, etc.Type 2 Blockboards, Commercial Type

These are blockboards with veneers ofcommercial timber on both sides and areused for ordinary furniture, table tops,partitions and panelling to be paintedover, flooring and seats of bus bodies,railway carriage, etc.

4.3 The grades and types of blockboards shallbe represented by the symbols given below:

5

Grade and Type

Exterior grade, commercial typeExterior grade, decorative typeInterior grade, commercial typeInterior grade, decorative type

MATERIALS

Symbol

XCOMXDECICOMIDEC

5.1 Timber

5.1.1 Any suitable species of timber may be usedfor blockboard manufacture. A list of speciesfor manufacture of blockboard is given inAnnex B for guidance.

5.1.2 Face Veneers for Decorat i ve Type ofBlockboards

A list of species for face veneers of decorativetype of blockboards is given in Annex C forguidance.

5.2 Adhesives

The adhesives used for bonding purposes shall bethe BWP type conforming to IS 848 : 1974 forGrade 1 blockboards. For Grade 2 blockboards,the adhesives shall be BWR or MR type con-forming to IS 848 : 1974.

6 MANUFACTURE

6.1 Preservative Treatment

Species of timber marked with ( t ) in Annexes Band C and sapwood of all species, and all non-durable species shall be treated as mentioned inIS 401 : 1982. Trimmed and cut ends of afinished blockboard shall be given a protectivetreatment.

6.2 Core

The wooden strips for core shall be cut outfrom timber seasoned to a moisture content notexceeding 12 percent according to IS 1141 : 1978.The width of each strip of wood shall not exceed30 mm. These strips may consist of specimensof small lengths placed end to end where theend joints shall be staggered. In any one block-board, the core strips shall be of one species oftimber only.

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IS 1659 : 1990

6.3 Crossbands and Faces

Veneers used for crossbands and faces shall beeither rotary cut or sliced and shall be reason-ably smooth.

6.3.1 Crossband shall be not less than 1.0 mmbut not more than 3.0 mm in thickness. Face

veneers shall be between 0.5 mm to 1.5 mm inthickness for commercial type of blockboardsand 0.5 mm to 1 O mm in thickness for decora-tive type of blockboards.

6.3.2 The construction shall be well balancedaround the central line.

6.3.3 Permissible defects and tolerances onthickness shall conform to IS 303 : 1989 andIS 1328 : 1982 for commercial and decorativeveneers, respectively.

7 DIMENSIONS AND TOLERANCES

7.1 Thickness

The thickness of blockboards shall be 12, 15, 19,25, 30, 35, 40, 45 or 50 mm.

7.2 Sizes

Blockboards shall be of sizes as prescribed inIS 12049 : 1987.

NOTE - Any other dimensions as agreed to betweenthe manufacturer and the purchaser may be used.

7.3 Tolerances

Tolerances on dimensions shall be in accordancewith IS 12049 : 1987.

8 SAMPLING AND 1NSPECTION

8.1 Scale of Sampling

8.1.1 Lo?

In any consignment, all blockboards of the samegrade, type and dimensions and manufacturedunder similar conditions shall be grouped toge-tber to constitute a lot.

8.1.1.1 The conformity of a lot to the require-ments of this standard shall be ascertained onthe basis of tests on blockboards selected fromit.

8.1.2 The number of blockboards to be selectedfrom a lot shall be in accordance with Table 1.

Table 1 Number of Blockboards to be Selected

8.1.2.1 These blockboards shall be selected atrandom. In order to ensure randomness of selec-tion, all blockboards in the lot may be arrangedin a serial order and every rth blockboard beselected till the required number is obtained, rbeing the integral part of N/n where N is the lotsize and n the sample size. For other methods of

random selection, IS 4905 : 1968 may be referredto.

8.1.3 Defects

All blockboards selected as in 8.1.2 shall be in-spected visually for surface defects ( see 6.3.3 )and if one or more blockboards are found un-satisfactory, the lot shall be declared as unaccep-table.

8.1.4 Length and WidthAll blockboards selected as in 8.1.2 shall havelength and width within the tolerances specifiedunder 7.3.

8.1.5 ThicknessAll blockboards selected as in 8.1.2 shall haveits mean thickness and variation in thickness ineach board as specified under 7.3 when tested bythe method described in Annex D.

8.2 Test Specimens and Number of Tests8.2.1 The selected blockboards as in 8.1.2 shallbe taken up for cutting of test specimens forfurther testing.8.2.2 From each of the blockboards selected,following test specimens shall be cut from theportion 150 mm away from the edges: i

a) Three test specimens of size 200 mm x

b)

cl

d)

e>

f1

Lot Size Number of Blockboardsto be Selected

g)

12 mm for thi test mentioned in 9.2.2;Three test specimens of size 200 mm x100 mm for the test mentioned in 9.2.3;

Three test specimens of size 150 mm x100 mm for the test mentioned in 9.2.4;Three square test specimens of size (14 d)+ 50 mm for the test mentioned in9.2.5 (a), if required; d being the averagelhickncss of the specimen in millimetres;Three test specimens of size 200 mm x!OO mm for the test in 9.2.5(b), if required;Three test specimens of size ( 36 d+ 100 )x 150 mm for the test mentioned in 9.2.5(c), if required where d is the nominalthickness m millimetres; andSix test specimens of size 200 x 12 mmfor the test mentioned in 9.2.1.

N

(1)up to 100101 to 300301 to 500501 and above

b,2358

8.2.3 The test specimens so obtained shall beconditioned in accordance with 9.1 and thethickness of each test specimen shall be measuredby the method given in Annex D and the meanof all such measurements calculated. The testspecimens shall then be tested for the corres-ponding tests.

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IS 1659 1990

IS No.

303 : 1989

401 : 1982

707 : 1976

848 : 1974

ANNEX A

( Clause 2.1 )

LIST OF INDIAN STANDARDS REFERRED IN THIS STANDARD

Ti t l e IS No.

Specification for plywood for 1141 : 1978general purposes ( third revi-sion ) /

Code of practice for preserva- 1328 : 1982tion of timber ( third revision )Glossary of terms applicable fortimber technology and utiliza-tion ( second revision ) 4905 : 1968Specification for synthetic resinadhesives for plywood ( pheno- 12049 : 1987lit and animoplastic ) (firstrevision )

Ti t l e

Code of practice for seasoningof timber (first revision )

Specification for veneereddecorative plywood ( secondrevision )

Methods for random sampling

Dimensions and tolerancesrelating to wood based panelmaterials

ANNEX B

( Clauses 5.1.1 and6.1 )

TIMBER FOR BLOCKBOARD ( OTHER THAN FOR FACE VENEERS OFDECORATIVE TYFE BLOCKBOARDS )

NOTE - Species of timber to be treated ( see 6.1 1 are indicated Py (t).

Standard Botanical Name Abbrevia-Trade Name

Aini Artocarpus hirsutus

-1Ald zr Alnus spp.Amari Amoora spp.Arj un Terminalia arjunatBahera Terminalia bellerica

Benteak Lagerstroemia lanceolata

Birch Betula spp.Bonsum Phoebe spp.jcarallia Carallia brachiata

( Maniawga ) ( Syn. C. integerrima )

ChampChaplashChikrassy

-fChilauniChir

CinnamonDebdaru

( Nedunar )Deodar

Michelia spp.Artocarpus chaplashaChukrasia velutina

( Syn. C. tabularis )Schima wallichii

Pinus roxburghii( Syn. P. Longifoli a )

Cinnamomum spp.Polyal thia spp.

CHMCHPCHI

CHLCHR

CINDEB

Cedr us deodara DE0

t i on

AIN

ALDAMAARJBAHBENBTRBONCAR

4

StandardTrade Name

Devdam

+DilleniaDipika

( Lapse )Ebony

FirGamariGendelipoma?Gokul

Gurjan

HalduHathipailaHollockHollong-i_Jaman*Jhingan

Botanical Name Abbrevia-t ion

Dy soxylum binectariferum DEV

Dil lenia spp . DILMansonia dipikae DIP

Diospyros spp. ( other EBOthan Diospyrosmormorata )

Abies spp. FIRGmeli na arborea GAMDysoxylum hamil toni i GENAilandhus integrifolia GOK

( Syn. A. grandis )Dipterocarpus spp. ( other GUR

than D. macrocarp us )Adina cordifol ia HALPterospermum acerifolium HATTerminalia myriocarpa HOLDipterocarpus macrocarpus HONSyzygitrm spp. JAMLannea coromandelica JHI

( Syn. Lannea grandis )


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StandardTrade Name

tKai1

-fKanj u-fKarani

Kathal

KindalKokkoLakooch-&ampat i

Laurel

Machilus

Mahogany-fMainaMakai-i-MangoMapleMullilam

TMundan iPali

Botanical Name Abbrevia-t ion

Pinus w all ichiana KAL( Syn. P. excel sa )

Holoptelea integrifolia KANCullenia rosayroana KAR

( Syn. C. excel sa )Artocarpus heterophyllus KAT

( Syn. A. integrif oli us )Terminalia paniculata KINAl bizi a l ebbeck KOKArtocarpus lakoocha LAKDuabynga grandiflora LAP

( Syn. D. sonneratioides )Terminalia alata LAU

( Syn. T. cori aceo,T. crenulata )

Machi lus spp. MAC

Sw ietenia spp. MAGTetr ameles nudif ora MAIShorea assamica MAKM angifera spp. MANAcer spp. MAPZanthoxylum rhetsa MUI

( Syn. Fagara budrunge;Z. budurunga ; Z. li monell a )

Acrocarpus fraxinifol ius MUNPalagquium ellipticum PAL

StandardTrade Name

fPine y

PoonPussurPpinma

Red Bombwe

l_Red DhupRosewoodSilver OakSissoo

TSpruce

TeakToon

tVaticeTVelIapineWalnut

TWhiteBombwe

White Cedar

TWhiteChuglam.

tWhite Dhup

IS 1659 : 1990

Botanical Name Abbrevia-i ion

Ki ngiodendron pi nnatum PIN( Syn. Hardwickia pinnata )

Calophyllum spp.Xylocarpus spp.Lagerstroemia hypoleuca

Planchonia vali da( Syn. P. andamanica )

Parishia insignis

Dalbergia l a t i j ol ia

Grevillea robusta

Dalbergia sissoo

Picea smithiana( Syn. P. morinda )

Tactona grandis

Toona ciliata( Syn. Cedrela t oona )

Vatica spp.Vateria indica

Juglans regia

Terminalia procera

Dysoxylum malabaricum

Terminalia bialata

PO0PUSPYI

RBO

RDtiROSSOASIS

SPR

TEATOO

VATVELWAL

WBO

WCE

WCH

Canarium spp. WDH

ANNEX C

( Clauses 5.1.2 and 6.1 )

TIMBER FOR FACE VENEERS OF DECORATIVE TYPE BCOCKBOARDS

NOTE - Species of timber to be treated ( see 6.1 ) are indicated by ( i ).

StandardTrade Name

BirchBela

ChampChaplashChikrassy

CinnamonDevdamDipika

( Lapse)Gendelipoma

Botanical Name StandardTrade Name

Botanical Name

Symbol

Betula spp. BIRM orus laevigata BOL

Michelia spp. CHMArtocarpus chaplasha CHPChukrasia velutina CHI

( Syn. C. t ebulari s )Cinnamomum spp. CINDysoxylum binectnriferum DEVMonsonia dipikao DIP

Dysoxylum hamil toni i GEN

TKanju

Kokko

Laurel

MahoganyMakaiMapleMullilam

Abbrevi-ated

Symbol

Holoptelea integrifolia KAN

Al bizi a l ebbeck KOK

Terminalia alata LAU( Syn. T. coriacea;T. crenulat a )

Sw ietenia spp. MAGShorea assamica MAKAcer spp. MAPZanthoxylum rhetsa MUI

( Syn. Fagara budrunga;Z. budrunga; Z. limonella )

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TS 1659 : 1990

StandardTrade Name

Botanical Name

Narikel

Padauk

PoonRosewood

Siris

Pterygota alata

Pterocarpus dalbergicides

Calophyllum spp.

Delbergia latifolia

Albizia chinensis( Syn. A. sti pulata )

Abbrevi-ated

Symbol

NAR

PAA

PO0ROS

SIR

StandardTrade Name

Sissoo Dalbergia sissoo

Teak Tactona grandis

Walnut Juglans regiaWhite Cedar Dysoxylum malabaricum

tWhite Terminalia biolataChuglam ( Sapw ood )

Botani cal Name Abbrevi -ated

Symbol

SIS

TEA

WALWCE

WCH

ANNEX D

( Clauses 8.1.5 and 8.2.3 )

TEST FOR THICKNESS AND VARIATION IN THICKNESS

D-l PROCEDURE be taken approximately 20 mm inside the edgesof the test pieces, namely, at four corners, and

D-l.1 Each board shall be tested for thickness. at midpoints of the long edges.

D-1 .l. 1 Thickness D -2 REPORTING OF TEST RESULTS

The thickness shall be measured in millimetres D-2.1 The mean thickness of each of the testto an accuracy of f O-02 mm. Six readings shall pieces shall be reported.

ANNEX E( Clause 9.2.1 )

FOR DETERMINING CHANGES BY HUMIDITY

EL 1 PROCEDURE

E-l.1 test specimens shallin atmosphere maintained 27 &- C and

65 & percent relative humidity constantmass. length of test specimen bemeasured an accuracy f 0.5 makinguse a jig permits the piece topressed against flat plate eliminate the

of any that may occurred. Theof each specimen shallmeasured, to accuracy of mm atmarked points, at each and one themid-point of length.

E-l.2 the number these testshall then placed in atmosphereed at f 5 and the half in f5 relative humidity 27 f and

they be weighed measured fromt3 time such intervals as be required

constant mass dimensions are obtain-

E-2 REPORTING OF RESULTS

E-2.1 in and thickness ascompared those of test

specimen be reported each testmen at relative humidity.

NOTE If a humidity is notthe required atmospheres be obtained

approximately by an airtight containingmoist salts follow:

90 relative humidity : Sodium carbonate65 percent relative humidity : Ammonium nitrate40 percent relative humidity : Magnesium chloride

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IS 1659 : 1990

ANNEX F( Clauses 9.2.2.1 and 9.2.2.2 )

TEST FOR DETERMI NING RESISTANCE TO WATER

F-l PROCEDURE

F-l.1 For testing of Grade 1 blockboards, testspecimens shall be submerged in a Span of coldwater, care being taken that the pieces do nottouch the bottom of the pan. Water shall thenbe brought to the boiling temperature andmaintained at this temperature for 72 hours.The test specimens shall then be removed fromthe boiling water and plunged immediately intocold water. The 72-hour period may be reckonedas an aggregate of shorter periods of boiling,the test specimens being left in cold waterbetween such periods when the water is notboiling.

F-l.2 For testing of Grade 2 blockboards the

test specimens shall be submerged in a pan ofcold water, care being taken to see that they donot touch the bottom of the pan. Water shallthen be brought to the temperature of 60 &PCand maintained at this temperature for 3 hours.The test specimens shall then be removed fromthe hot water and plunged immediately intocold water.

F-2 REPORTING OF TEST RESULTS

F-2.1 The results shall be reported as passstandard, excellent or poor after carrying outthe tests as in Annex H.

ANNEX G( Clause 9.2.4 )

MYCOLOGICAL TEST

,G-1 PROCEDURE

G-l.1 A flat rectangular dish of enamelled iron,glass or porcelain ( such as a photographicdeveloping dish ) shall be filled to a depth notless than 25 mm with a layer of sawdustobtained from a non-durable timber like Semul( Salmal ia rnalabarica ), in its natural condition.

The sawdust shall have previously been moisten-ed with water containing 14 g per litre of sucrose( normally cane sugar would be used but if notavailable, 30 g of commercial malt extract maybe substituted ) so that it is saturated withmoisture, but not so wet that free water can besqueezed out of it by hand pressure. To attainthis condition with dry sawdust, it is usuallynecessary to add water three times its mass.

G-I.2 The sawdust shall then be charged withspores of commonly occurring Indian fungiloosely campacted, and the test specimens then

pressed down into it so that their upper surfaceare in level with the top of the sawdust layer.

G-l.3 The. dish shall then be covered with asheet of glass and the edges (of the dish sealedagainst glass with a strip of material, such as,modelling wax, so that the atmosphere roundthe test specimens shall remain saturated with

water vapour.

G-l.4 The dish and contents shall be maintainedat 27 & 2 C for a period of 3 weeks, after whichthe test specimens shall be removed, washed in,cold water until cool and whilst still water soak-ed, shall be checked for compliance with therequirements of 9.2.4.

G-2 REPORTING OF TEST RESULTS

G-2.1 The test results shall be reported as con-forming to the standard or otherwise.

ANNEX H( Clauses 9.2.3 and F-2.1 )

TEST FOR ADHESION OF PLIES

H-l APPARATUS H-l.2 The test shall be carried out on a stout

H-l.1 The type of knife required to be used in table to which is screwed a wooden batten

the test is given in Fig. 1. It may be made from against which the edge of the test specimen is

.a file. The cutting edge should be kept chisel placed as indicated in Fig. 2.

sharp.

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IS 1659 1990

A KNIFE OF THIS KIND CAN BE

MADE FROM 250 X 25mm FILE

I25 mm

f

FIG. 1 KNIFE FOR TESTING PLYWOOD FQR ADHBSION OF PLIBS

FIG. 2 METHOD OF TESTING FOR ADHBSION

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IS 1659 : 1990

H-2 PROCEDURE

H-2.1 The knife is inserted with its cutting edgeparallel to the grain of the outer veneer andworked into, or if possible, along a glue lineand the veneer is prised upward. A hard anddense species requires considerable force toeffect entry and to prise the veneer. In a softspecies, the knife tends to follow an easy coursethrough the wood and in this case, it is essentialthat the knife be firmly guided along the glueline.

H-2.2 Example of cases when the bond justpasses the requirement is indicated in Fig. 3 andthis is judged by the relative amounts of woodfibre left on the core veneer, and the areaprised off. The grading is assessed chiefly on theappearance of the break but is a concomitantrequirement that the force shall be needed toeffect separation.

H-2.3 The bond is excellent when it is difficultto find the glue line and impossible to keep the

tool within it for more than 6 mm without cutt-ing into adjacent wood. On prising upwards,the veneer usually breaks off over a width onlyslightly greater than that of the tool. Examplesof excellent bond are illustrated in Fig. 4.

H-2.4 The bond is poor when the knife meetslittle opposition into the glue line and the priseresults in the easy removal of almost all theveneers from one side of the test specimen. Theseparated veneers are usually almost free fromadherent fibre. Examples of poor bond areillustrated in Fig. 5.

H-3 REPORTING OF TEST RESULTS

H-3.1 The results shall be reported as passstandard, excellent or poor ( see Fig. 3, 4and 5 ). Blockboards designated as poor shallbe declared as unsatisfactory.

H-4 TEST FOR GLUE ADHESION BETWEENCORE AND ADJOINING VENEERS

H-4.1 To test the glue adhesion between thecore and the adjoining veneers and also to testthe glue adhesion between battens of core, ifrequired, the qualitative test as given in H-4.1.1may be used.

H.4.1.1 The central core strips shall be forciblyseparated from its adjacent veneer by a chiselinserted in the bond line and affecting the sepa-ration in the direction of the core strips. Thecapacity of the bond should be judged by therelative amount of wood fibres left by the veneerand the core strips. Force shall be needed toeffect the separation. The grading should be

assessed on the basis of the appearance of thefailure. The bond should be condsidered exce-llent when it is difficult to find the glue lineclearly for more than 10 mm length along thebattens and on its entire width without tornfibres appearing on the area of separation. Thebond should be Tconsidered as cpoor when thechisel meets little opposition in the glue lineand if there is an easy separation between thecore strips and the veneers. If the glue adhesionbetween battens of the core in a blockboard inwhich the core strips are bonded is to be tested,a similar procedure and criteria may be followed.

.

FIG. 3 EXAMPLE OF MINI MUM PASS STANDARD


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IS 1659:1990

FIG. 4 EXAMPLES OF EXCELLE NT ADHESION

FIG. 5 EXAMPLES OF POOR ADHESION - continued

10


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ISi1659 : 1990

ANNEX K[ Clause 9.2.5 (b) ]

FLEXURAL STRENGTH TEST

K-l.1 Each test specimen shall be simply sup-ported on parallel rollers having a radius of 10to 12 mm, spaced at 150 mm centre-to-centreand free to rotate in ball or roller bearings. Aload shall then be applied at the centre of thespan along a line parallel with the end supportsby means of a bar rounded to a radius between10 and 12 mm.

K-2.1.1 The effective modulus of rupture (f)shall be calculated as follows:

K-l PROCEDURE

K-1.1.1 The load shall be applied at an even rateor at a rate such as will produce an even rate ofincrease in strain, and shall be so adjusted thatthe test will be completed in a period of notless than half a minute and not more than4 minutes.

K-2 REPORTING OF TEST RESULTS

K-2.1 The ultimate load at which each testspecimen fails and the mean of these loads shallbe reported. The effective modulus of rupturecalculated as given in K-2.1.1 shall also bereported.

3 wsf = 2 N/mm%where

W = mean ultimate failing load in N to thenearest N or to within O-5 percent of-the load,

s = measured span between centres ofsupports ( 150 mm ),

b - mean width of test specimens in mm,.and

d - mean thickness of test specimens inmm.

NOTES

1 Repeat the strength tests and record separateresults for test specimens cut parallel with, and atright angles to the grain.2 If the flexural strength when wet is required, thetest specimens shall be immersed in water for 24hours. The test specimens shall then be tested imme-diately for flexural strength and the effective modulusof rupture determined as above.

ANNEX L[ Clause .2.5 (c) ]

DEFLECTION UNDER SUSTAINED LOAD TEST

L-l PROCEDURE

El.1 Each test specimen shall be supported onhorizontal parallel rollers having a radius of 10to 12 mm, spaced at a centre-to-centre distanceof 36 times the nominal thickness of the board.The test load shall be applied at the mid-pointof the span along a line parallel to the endsupports by means of a bar rounded to a radiusof 10 to 12 mm and carrying a stirrup, fromwhich a mass shall be suspended so that the totalmass including the bar and the stirrup shall be1 kg. The position assumed under this initial loadafter a period of 30 seconds shall be treated asthe zero condition.

L-l.2 An additional mass of 5 kg shall then besuspended from the stirrup and the deflection

sustained after a period of 24 hours ( and atintermediate period if so desired ) shall bemeasured to an accuracy of O-1 mm.

L-l.3 The 5 kg mass shall then be removed afterthe lapse of a further period of 24 hours and theresidual deflection, measured from the zero con-dition defined in L-1.1, shall be determined toan accuracy of O-1 mm.

L-2 REPORTING OF TEST RESULTS

L-2.1 The deflection after 24 hours under loadand the residual deflection after removal of the-load shall be reported for each test specimentogether with the mean deflection and the meanresidual deflection.

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Standard Mark

The use of the Standard Mark is governed by the provisions of the Bureau of IndianStandards Act, 1986 and the Rules and Regulations made thereunder. The Standard Mark onproducts covered by an Indian Standard conveys the assurance that they have beenproduced to comply with the requirements of that standard under a well defined system ofinspection, testing and quality control which is devised and supervised by BIS and operatedby the producer. Standard marked products are also continuously checked by BIS for con-formity to that standard as a further safeguard. Details of conditions under which a licencefor the use of the Standard Mark may be granted to manufacturera or producers may beobtained from the Bureau of Indian Standards.


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Users of Indian Standards should ascertain that they are in possession of the latest amendments ordition by referring to the latest issue of BIS Handbook and Standards Monthly Additions.omments on this Indian Standard may be sent to BIS giving the following reference:

Dot No. CED 20 ( 4583 )

Amendments Issued Since Publication

Amend No. Date of Issue Text *Affected

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I331 01 31331 13 75

I37 84 99, 37 85 6137 86 26, 37 86 62

153 38 43, 53 16 4053 23 84

I235 02 16, 235 04 42235 15 19, 235 23 15

I632 92 95, 632 78 58632 78 91, 632 78 92

AHMADABAD. BANGALORE. BHOPAL. BHUBANESHWAR.COIMBATORE. FARIDABAD. GHAZIABAD. GUWAHATI. HYDERABAD.J AIPUR. KANPUR. LUCKNOW. PATNA. THIRUVANANTHAPURAM.

Printed at New India ninth Press Kburla India


17/21

AMENDMENT NO. 3 SEPTEMBER 1997TO

IS 1659 : 1990 BLOCKBOARDS - SPECIFICATION

(ThirdRevision)

[ Page 2, cl ause 83.2(a) ] - Substitute 200 mm x 100 mm for 200 mm x12 mm.

(CED20)Repmgnphy Unit, IS, New De&i, India


18/21

AMENDMENT NO. 4 APRIL 1999TO

IS 1659 : 1990 BLOCKBOARDS - SPECIFICATION

( Thi rd Revkim )

[ Page 2, clau se 83.2 (d)] - Substitute the following for the existing:

Three test specimens each of size having (50 mm + 14 d) length and 75 mmwidth in full thickness of board for the test mentioned in 9.2.5, where d is thenominal thickness in mm. Greater dimension shall be in the direction along theface grain.

[ Page 2, clause 82.2 (e) ] - Delete.

[ Page 2, clause 8.2.2 (f) ] - Delete.

(Page 3, clause 9.2.5 ) - Substitute the following for the existing:

9.25 MoaWus of Rupture and Modulus of Elastici ty

9.2.5.1 The modulus of rupture and modulus of elasticity when tested accordingto the method given in IS 1734 (Part 11) : 1983 Methods of test for plywood:Part 11 Determination of static bending strength, Grade I and Grade II boardsshall give a minimum average value of 50 N/mm* and 40 N/mm* respectivelyfor modulus of rupture and 5 000 N/mm* and 4 000 N/mm* respectively formodulus of elasticity.

(Page 10,Annex J ) - Delete.

(Page 11, Amex K) - Delete.

( Page 11, Annex L ) - Delete.

(CED 20)

Reprography nit, BIS, New Delhi, India


19/21

AMISNOMIOCKUOARDS - SPECIIICATION

( J h i r d ev i si o n )

( Secon d cmwr pure, F orcwurd) - Insert the kollowi~~g aficr third para as aseparate para:

A scheme of I;\hclling c\\viro\\t\\c\\t friendly products to be kr\own as EC0 Markhas Ixccn i\\trodurcd at the i\\st;\r\cc of the Mi\\istry of E\\viro\\\\\cnt and Forests(MEF), Goverunlent ot India. The EC0 Mark shall be administered by theBUWaU Of I \ \ di i \ t l SCllldilKlS (131s) urrdcr the B/S Act, 1W6 as per the ResolutionNo. 71 dated 2 I February 1091 and Resolution No. 425 dated 28 October 1992p\\l\lishcd in the Gazette of IIIC Govcrruuent 01 India. For a product to bc cligiblc

for EC0 Mark, it sl\all also carry the Standird Mark of the BIS bcsidcs meeting;\clditior\;\l c\\vin\r\r\\r\\t fric\\dly rrc~i\ircr\\c\\ts. For this purpose, the Sta\\dardM;\rk of BIS would bc II si\\Elc r\\ark lxing a ror\\bi\\;\tio\\ of the ISI M;\rk a~\dthe Eco logo. Rcquirc\\\c\\ts to Ix satisfied for a product to qualify for tl\c BISSt;\\\dard Mark Par Eco Lric\\dlincss, will bc included in the rclcvant publishedIritlian Sta\\dards ttirough an ;1111r1idii~cn1. Thcsc requirements will be optional;\\\ai\ufacturing ur\its wiH lx Prce to opt for ISI Mark alone also.

Ihc ar\\cr\d\\\c\\t pcrt;\i\\i\\g to EZco criteria is based on the Gazette NotificationNo. 170 dated 1X May 1996 Li\r Wood Substitutes as Environment FriendlyProducts published in tt\c Gazette of the Govcrenment of India.

( I~,qe 1, clurtse 5.1 I ) - Insclrt the rollowing at the end of the clause:

For EC0 Mark only spccics of wood from sources other than natural forestssuch as wood from r\\l\l\rr, coconut, caahcw, iildustrial arid social li\restryi\l;\\\t;\ti(>\\s, ctc a\\d shdc trees Irom tea and colrcc cstatcs shall be used Ibr themanufacture ofblockboard.

( Pclge 1, dnuse 5.1.2 ) - IIISC~I the following at the end or the clause:

For EC0 Mark only spccics of wood liom sources other than natural Ibrcstssuch as wood firm rubber, coconut, cashew industrial aud social forestry

-plautatious, rtc and shade trcrs Pnm ten and colfce cstatcs shall bc used Ihr I$Tvcnccrs oldccorativc type blocklxbards.

( PCI~ 2, clmrse 6.3.3 )-Substitute IS 1328:1996fr,r IS 1328:1982.

1


20/21

Amend No. 5 to IS 1659 : 1YYO

[ Pcrgc 3, clarcse 9.2.5.1 ( see also Am endment No. 4 ) ] - Insert thelitllowirtg nrw ch~usc nllcr 9.2.5.1 and rettuntbcr Htc suhscqucnl clasucs:

10 OIIIONAI, IWQ~JIWEMENTS FOR EC0 MARK

10.1 General Requirements

~10.1.1 The blockboard shall conforttt to the rcquircntcnfs of quality andpcrfortttancc as spccificd in this standard.

10.1.2 The manufacturer shall produce to BIS environmental consent clearancefront the conccrncd State Pollution Control Board as per the provisions of theWater (Prevention and Contro l of Pollut ion) Act , 1974 and Air (Prevention andContro l of Pohion ) Act , 1981, and Water (Prevention and Contro l ofPollu tion ) Cess Ac t, 1977

along with the authorization, if required under theEnvironment (Protect ion) Act, 1986, while applying for EC0 Mark appropriatewith enforced rules and regulations of Forest Department.

10.2 Specific Recptirements

-The blockboard shall conTorn to the specific rcquirctttcnts given for EC0 Markunder tclcvant clauses of the standard.

NOTE -The manufacturer shall provide documentary evidence by way of certificate ordeclaration IO Hureau of Indian Standards while applying for EC0 Mark.

( fqe 3, rowmbered c lause 11.1 ) - lnscrt the following ntatlcr under (hcclause:

c) The criteria for which the blockboard has been labelicd as EC0 Mark.

( Ptr~:e 3, Annex A ) - Substilutc IS 1328 : 1996 Vcnccrcd dccorativcplywood - SpccificaGott (r l r i rd revision) for 1s 1328 : 1982 Specification forvc*ttccrcd dcrorativc plywood (second revision) .

( Page 3, Annex A ) - Insert the following between 1328 : 1982 and4905 : 1968:

1734 ( Part 11 ) : 1983 Methods of test for plywood : Part 11 Determination afstatic bcndittg strcrtgth (second revision)

( CED 20 )

Reprography Unit, BE, New Delhi, India

2


21/21

AMENDMENT NO. 6 AUGUST 2002

IS 1659:1990 BLOCKB&lDS SPECIFICATION

( Third Revkwn)[ Page 1, clause 5.1.2 ( see also Amendment No. 5 ) ] Substitute the

following for the existing:

5.1.2 Face Veneers for Decorative Type of Blackboards

The species of timber for the decorative face veneer in decorative type ofblackboard shall be specified by the purchaser while placing the order. Thespecies of timber commonly used for face veneers of decorative type of

blackboard is given in Annex C for guidance.( Page 1, clause 6.1, fast entence) Substitute Trimmed and cut ends of

a finished blackboard may be given a protective treatment. for Trimmed andcut ends of a finished blackboard shall be given a protective treatment.

( Page 2, clause 7.3) Substitute the following for the existing clause:

7.3 Tolerances

The following tolerances

permissible:

DimensionLangtb

( CED 20 )

Wi d t h

TlickrlessSquareness

on the nominal sizes of finished boards shall be

Tolerance*mm-omm+3 nun-o mm

*5%0.2%

Edge straightness 0.2%

,.

.

Reprography UniL BIS, New Delhi, India

1659 Block Boards

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