_API_STD_2000-2014.pdf

Venting Atmospheric andLow-pressure Storage TanksAPI STANDARD 2000SEVENTH EDITION,MARCH 2014ener光1AMERICAN PETROLEUM INSTITUTENo roproduction or notworking permitled without liconso from IHSNot for RosaleSpecial NotesAPI publications necessarily address problems of a general nature.With respect to particular circumstances,local,state,and federal laws and regulations should be reviewed.Neither API nor any of APIs employees,subcontractors,consultants,committees,or other assignees make anywarranty or representation,either express or implied,with respect to the accuracy,completeness,or usefulness of theinformation contained herein,or assume any liability or responsibility for any use,or the results of such use,of anyinformation or process disclosed in this publication.Neither API nor any of APIs employees,subcontractorsconsultants,or other assignees represent that use of this publication would not infringe upon privately owned rights.Users of this standard should not rely exclusively on the information contained in this document.Sound business.scientific,engineering,and safety judgment should be used in employing the information contained herein.Whereapplicable,authorities having jurisdiction should be consulted.API publications may be used by anyone desiring to do so.Every effort has been made by the Institute to assure theaccuracy and reliability of the data contained in them;however,the Institute makes no representation,warranty,orguarantee in connection with this publication and hereby expressly disclaims any liability or responsibility for loss ordamage resulting from its use or for the violation of any authorities having jurisdiction with which this publication mayconflict.API publications are published to facilitate the broad availability of proven,sound engineering and operatingpractices.These publications are not intended to obviate the need for applying sound engineering judgmentregarding when and where these publications should be utilized.The formulation and publication of API publicationsis not intended in any way to inhibit anyone from using any other practices.Any manufacturer marking equipment or materials in conformance with the marking requirements of an API standardis solely responsible for complying with all the applicable requirements of that standard.API does not represent,warrant,or guarantee that such products do in fact conform to the applicable API standard.All rights reserved.No part of this work may be reproduced,translated,stored in a retrieval system,or transmitted by any means.electronic,mechanical,photocopying,recording,or otherwise,without prior written permission from the publisher.Contact thePublisher,API Publishing Services,1220 L Street,NW,Washington,DC 20005.Copyright 2014 American Petroleum InstituteNo roproduction or notworking permitled without liconso from IHSNot for RosaleContentsPage1Sc0pe12Terms,Definitions,and Abbreviated Terms.13Nonrefrigerated Aboveground Tanks.33.1General.33.2Causes ofOverpressure or Vacuum.43.3Determination of Venting Requirements.3.4Means of Venting03.5Considerations for Tanks with Potentially Flammable Atmospheres.213.6Relief-device Specification.223.7Installation of Venting Devices and Open Vents.34Refrigerated Aboveground and Belowground Tanks.244.1General.244.2Causes of Overpressure or Vacuum.254.3Relief-deviceSpecification.284.4Installation of Venting Devices.85Testing of Venting Devices.25.1Ceneral.2g5.2Flow-test Apparatus.295.3Method for Determining Capacities.335.4Production Testing46Manufacturers Documentation and Marking of Venting Devices.356.1Documentation.56.2Marking.35Annex A(informative)Alternative Calculation of Normal Venting Requirements.37Annex B(informative)Basis of Emergency Venting for Table 7 and Table 8.46Annex C(informative)Types and Operating Characteristics of Venting Devices.51Annex D(informative)Basis of Sizing Equations.59Annex E(informative)Basis for Normal Out-breathing and Normal Inbreathing.73Annex F(informative)Guidance for inert-gas Blanketing of Tanks for Flashback Protection.75Annex G(informative)Explanation of Differences in Thermal Inbreathing Using the General Methodand Annex A Method.78Bibliography.83Figures1Test Apparatus for Flow Testing of Venting Devices.302Typical Ratio Limits for Capacity Testing of Venting Devices Using the Coefficient ofDischarge Method.33B.1 Curve for Determining Requirements for Emergency Venting During Fire Exposure(SI Units).49B.2 Curve for Determining Requirements for Emergency Venting During Fire Exposure(USC Units).50C.1Open Vent.51C.2Side-by-side Pressure/Vacuum Vent.,.,.,.,.,.,54C.3 Large,Weight-loaded Emergency Vent.54No roproduction or notworking permitled without liconso from IHSNot for Rosale