ISO INTERNATIONAL STANDARD 9709 Secondedition 2018-10 Structural timber - Visual strength grading Basic principles Bois de structure-Classement visuelle selon la resistance- Principesdebase Referencenumber IS09709:2018(E) so @IS02018 IS09709:2018(E) COPYRIGHTPROTECTEDDOCUMENT @ISO2018 All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either IsO at the address below orIso's memberbody in the countryof therequester. ISO copyright office CP 401 : Ch. de Blandonnet 8 CH-1214 Vernier, Geneva Phone:+41227490111 Fax:+4122749 09 47 Email: [email protected] Website: www.iso.org Published in Switzerland ii @ IS0 2018 - All rights reserved IS0 9709:2018(E) Contents Page Foreword ..iv Introduction. ..V 1 Scope. .1 2 Normative references ..1 3 Terms and definitions ..1 4 Symbols and abbreviated terms .4 5 General. .4 5.1 Visual strength-graded timber. .4 5.2 Visual strength-grading operations .4 5.3 Visualstrength-gradingprinciplesofqualitycontrol .4 6 Resourceand sawntimberinputrequirements. .4 6.1 General .4 6.2 Input requirements .5 6.2.1 Resource. .5 6.2.2 Sawntimber 5 6.3 Controlofinputs .5 6.4 Reprocessing of previously graded material .5 7 Visual strength-grading requirements .5 7.1 Graderrequirements .5 7.2 Grading process .5 7.2.1 General .5 7.3 Grading to satisfy structural requirements .6 7.3.1 Structuralfeatures .6 7.3.2 Measurementofstructuralfeatures .6 7.3.3 Frameworkforstructuralrequirements .7 7.4 Gradingtosatisfytheutilityrequirements .7 7.4.1 Utility features 7 7.4.2 Measurementofutilityfeatures 7.5 Check on visual grading process. .10 8 Visualgradedtimberstructuralproperties .11 8.1 General .11 8.2 Initial evaluation .11 9 Productidentification ..11 10 Documentation .11 Annex A (informative) Example of a visual strength-grading timber standard-based on theneedfor designvalueswhere a degree ofcertainty of structuralproperties is required .13 Annex B (informative) Example ofa visual strength-grading timber standard based on the needfor designvalueswhereahigh degree of certainty of structuralproperties is notrequired .21 AnnexC (informative)Exampleofaframeworkforstructural gradingprovisions .25 AnnexD (informative)Exampleofvisualstrengthgradingfortropicalhardwoodtimber ..29 Annex E (informative) Training, supervision and oversight ofgrading .38 Bibliography .39 @ IS0 2018 -All rights reserved ili