ISO INTERNATIONAL STANDARD 6420 Second edition 2016-10-01 Hydrometry Position fixing equipment for hydrometric boats Hydrométrie - Systeme de positionnement pour embarcation hydrométriques Reference number ISO 6420:2016(E) ISO @ ISO 2016 IS0 6420:2016(E) COPYRIGHT PROTECTED DOCUMENT @ IS0 2016, Published in Switzerland All rights reserved. Unless otherwise specified, 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 or ISO's member body in the country of the requester. ISO copyright office Ch. de Blandonnet 8 . CP 401 CH-1214 Vernier, Geneva, Switzerland Tel. +41 22 749 01 11 Fax +4122 749 09 47 copyright@iso.org www.iso.org Copyright ihtermational Organization for Standardization @ IS0 2016 - All rights reserved IS0 6420:2016(E) Contents Page Foreword ..iv Introduction. .V 1 Scope. ..1 2 Normative references 3 Terms and definitions 4 Requirements for position fixing ..1 5 Position fixing equipment for streamgauging and sediment sampling ..1 5.1 General .1 5.2 Tapes and tag lines. .2 5.3 Global navigation satellite systems .2 5.3.1 General. 2 5.3.2 Hvdrometricapplication .3 5.3.3 System specifications. 3 5.4 Targets and electronic distance measuring equipment. 3 5.4.1 General 3 5.4.2 Targets 3 5.4.3 Electronic distance measuring devices .3 5.5 Electronic survey instruments. .4 5.6 Theodolites. ..4 5.6.1 Theodolites and stadia 4 5.6.2 Angular technique .4 6 Position fixing equipment for morphological surveys ..5 6.1 General .5 6.2 Global navigation satellite systems .5 6.3 Electronic surveying instruments 5 6.4 Theodolites and stadia rods. .6 7 Uncertainty .6 7.1 Definition of uncertainty .6 7.2 Uncertainty of position fixing for streamgauging and sediment sampling .7 7.2.1 General 7 7.2.2 Tag lines. .7 7.2.3 Globalnavigationsatellitesystem 7 7.2.4 Targets and distance measuring devices .8 7.2.5 Electronic surveying instruments. .8 7.2.6 Theodolites .8 7.3 Uncertainty of position fixing for morphological surveys .8 7.3.1 General .8 7.3.2 Global navigation satellite systems .9 7.3.3 Electronic surveying instruments .9 7.3.4 Triangulation method using theodolites .9 Annex A (informative) Evaluation of uncertainty components ..10 Bibliography .12 CopyightIntermational orgzSMiSaaraizAlh rights reserved iii