1、Preparing Tank Bottomsfor Hot WorkAPI RECOMMENDED PRACTICE 2207SIXTH EDITION, DECEMBER 2007REAFFIRMED, MARCH 2012Preparing Tank Bottomsfor Hot WorkDownstream SegmentAPI RECOMMENDED PRACTICE 2207SIXTH EDITION, DECEMBER 2007REAFFIRMED, MARCH 2007Special NotesAPI publications necessarily address proble
2、ms 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 any warranty or representation, either express or implied, with
3、respect to the accuracy, completeness, or usefulness of the information contained herein, or assume any liability or responsibility for any use, or the results of such use, of any information or process disclosed in this publication. Neither API nor any of APIs employees, subcontractors, consultants
4、, or other assignees represent that use of this publication would not infringe upon privately owned rights.API publications may be used by anyone desiring to do so. Every effort has been made by the Institute to assure the accuracy and reliability of the data contained in them; however, the Institut
5、e makes no representation, warranty, or guarantee in connection with this publication and hereby expressly disclaims any liability or responsibility for loss or damage resulting from its use or for the violation of any authorities having jurisdiction with which this publication may conflict.API publ
6、ications are published to facilitate the broad availability of proven, sound engineering and operating practices. These publications are not intended to obviate the need for applying sound engineering judgment regarding when and where these publications should be utilized. The formulation and public
7、ation of API publications is 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 standard is solely responsible for complying with all the applicable requirements of that stand
8、ard. 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, stored in a retrieval system, or transmitted by any means, electronic, mechanical, photocopying, recording, or otherwis
9、e, without prior written permission from the publisher. Contact the Publisher, API Publishing Services, 1220 L Street, N.W., Washington, D.C. 20005.Copyright 2007 American Petroleum InstituteForewordThis edition of API RP 2207, Preparing Tank Bottoms for Hot Work is significantly updated from prior
10、editions. The new Section 7 “Putting It All Together” provides a quick review and can be used to guide users to content in the body of the standard.Two API Individual Certification Programs (ICPs) are referenced in this standard. The API 653 Aboveground Storage Tanks Inspector Certification Program
11、evaluates individual personnel qualifications to inspect and determine conformance with API Std 653, Tank Inspection, Repair, Alteration, and Reconstruction. Because tank entry is often an integral part of the process the API Tank Entry Supervisor Individual Certification Program provides a tool for
12、 certifying supervisors who will evaluate hazards to minimize any risks associated with tank entry. API 2207 primarily discusses work practices which have been used safely and is not a regulatory compliance document. However, it does update the listing of potentially relevant regulations. Federal, s
13、tate, and local regulations or laws may contain additional requirements that must be taken into account when a tank repair program is developed for a specific facility. Since the essential elements of this publication are based on current industry safe operating practices and existing consensus stan
14、dards; these listings have also been updated and expanded. References made to “OSHA” refer to U.S. Federal regulations. Comparable or more restrictive requirements may exist in other jurisdictions (states or countries) and the appropriate requirements should be used. Where no regulations or other le
15、gal requirements exist, the OSHA standards provide a useful reference and are readily available for download from the internet at www.osha.gov.Nothing contained in any API publication is to be construed as granting any right, by implication or otherwise, for the manufacture, sale, or use of any meth
16、od, apparatus, or product covered by letters patent. Neither should anything contained in the publication be construed as insuring anyone against liability for infringement of letters patent.This document was produced under API standardization procedures that ensure appropriate notification and part
17、icipation in the developmental process and is designated as an API standard. Questions concerning the interpretation of the content of this publication or comments and questions concerning the procedures under which this publication was developed should be directed in writing to the Director of Stan
18、dards, American Petroleum Institute, 1220 L Street, N.W., Washington, D.C. 20005. Requests for permission to reproduce or translate all or any part of the material published herein should also be addressed to the director.Generally, API standards are reviewed and revised, reaffirmed, or withdrawn at
19、 least every five years. A one-time extension of up to two years may be added to this review cycle. Status of the publication can be ascertained from the API Standards Department, telephone (202) 682-8000. A catalog of API publications and materials is published annually and updated quarterly by API
20、, 1220 L Street, N.W., Washington, D.C. 20005.Suggested revisions are invited and should be submitted to API Standards Department, 1220 L Street, NW, Washington, DC, 20005. iiiContentsPage1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
21、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.1 Concepts of Hazard and Risk. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11.2 Relationship to Regulations. . . . . . . . . . . . . . . . . . . . . . . . .
22、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Referenced Publications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 Definitions . . . . . . . . . . . . . . . . . . . . . . . .
23、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74.1 General Precaution
24、s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74.2 Specific Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
25、. . . . 85 Inspection Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 105.1 General Inspection Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
26、 . . . . . . . . . . . 105.2 Specific Inspection Procedures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106 Work Procedures and Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
27、. . . . . . . . . . . . 106.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 106.2 Minor Repairs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
28、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116.3 Major Repairs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116.4 Perimeter Repairs . . . . . . . . . . . . . . . . . . . .
29、 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126.5 Double-bottom Installation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126.6 Sectional Repairs. . . . . . .
30、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 137 Putting it all Together . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13Anne
31、x A Inerting Vessels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Annex B OSHA Permit-required Confined Space Decision Chart . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19Bibliography . .
32、. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Figure1 Preparing a Tank for Repairs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
33、 . . 15vIntroductionThis recommended practice provides information to assist safe performance of hot work on the bottoms of storage tanks which have been in service to store flammable products. This work activity has specific precautions and work practices. The understanding of potential hazards, re
34、levant precautions and techniques, and application of this knowledge, can help improve safety performance and reduce the probability of incidents.Tanks that previously have contained flammable or combustible liquids, regardless of their age and type of construction, must be considered unsafe for hot
35、 work until inspected and approved by a qualified person. These inspections include visual examination and atmospheric testing to evaluate physical and atmospheric hazards (flammability, oxygen deficiency and potentially toxic contaminants). Emphasis is on special techniques required in the performa
36、nce of hot work to prevent the ignition of flammable gases or vapors that may be trapped under the tank bottom.Each repair of tank bottoms must receive careful consideration and individual evaluation. The safety procedures described in this recommended practice provide various methods which have bee
37、n used successfully for preparing tank bottoms for hot work. These procedures will apply to most situations: however, each job must be independently evaluated to assure safe work.Preparing Tank Bottoms for Hot Work1 ScopeThis recommended practice addresses only the safety aspects of hot work on petr
38、oleum storage tank bottoms. It discusses safety precautions for preventing fires, explosions and associated injuries. The term hot work, as used in this publication, is defined as an operation that can produce a spark or flame hot enough to ignite flammable vapors. API 2009 provides more in-depth in
39、formation on safe hot work practices and its requirements are not duplicated here.This recommended practice does not contain all safety precautions and procedures that may be required prior to, during, or after a specific hot work activity. All hot work should be performed in compliance with applica
40、ble national, state and local regulatory requirements and recognized industry practices. Work practices of concern for working on tank bottoms, include but are not limited to: confined space entry, lockout/tagout, atmospheric testing, ventilation, and requirements for use of PPE. ANSI/API 2015 and A
41、NSI/API 2016 provide guidance for tank entry consistent with OSHA regulations noted in the Section 2 References. This recommended practice does not repeat the extensively detailed information provided in those documents. Some of the relevant OSHA regulations from 29 CFR part 1910 and 29 CFR 1926 are
42、 included in the references. It is the responsibility of each organization to review and comply with applicable legal requirements.The scope of API 2207 does not include: guidance for compliance with safety or environmental regulations or codes. engineering specifications for tank construction or re
43、building (see API tank standards). specific guidance for repair of shop-fabricated tanks which is addressed by Steel Tank Institute SP031. These tanks include those built to UL 142, API 650 Appendix J, Steel Tank Institute aboveground tank standards, as well as others. specific guidance for tank ent
44、ry (see ANSI/API 2015 and ANSI/API 2016). welding techniques, craft skills or qualification of welders (see referenced welding standards). normal “safe work” practices such as fall protection, PPE, slip/trip/fall etc. entry or work in inert environments (see API 2217A).1.1 Concepts of Hazard and Ris
45、k Hazards are properties of materials (or situations) with the inherent ability to cause harm. Flammability, toxicity, corrosivity, stored chemical or mechanical energy all are hazards associated with various industrial materials or situations. Risk requires exposure. A fire or hot surface can cause
46、 thermal skin burns or a corrosive acid can cause chemical skin burns, but these can occur only if there is contact exposure to skin. In an empty tank a floating roof represents a “stored mechanical energy” hazard which might fall on persons working underneath, and so must be properly secured to red
47、uce risk of contact before performing entry work.There is no risk when there is no potential for exposure. Determining the level of risk involves understanding hazards and estimating the probability of exposure and severity of consequences that could lead to harm. While the preceding examples relate
48、 hazards to the risk to people, the same principles are valid for evaluating property risk. For instance, a flammable mixture of hydrocarbon vapors in air can ignite if exposed to a source of ignition, resulting in a fire that could damage property as well as injure people.12API RECOMMENDED PRACTICE
49、 22071.2 Relationship to Regulations This recommended practice aims to share practices which over time have been useful in injury prevention programs. The specifics of compliance with either safety or environmental laws or regulations fall outside the scope of this standard, but should be carefully reviewed by those authorizing and conducting work. 2 Referenced Publications The most recent editions of the following standards, codes, and specifications are cited in this publication. The Bibliography lists additional relevant references not specifically cited in the body of this stan
