1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA
2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any
3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ICS 13.340. 30 ISBN 0-626-14742-5 SANS 50250:2003 Edition 2 EN 250:2000 Edition 2 SOUTH AFRICAN NATIONAL STANDARD Respiratory equipment Open-circuit self
4、-contained compressed air diving apparatus Requirements, testing, marking This national standard is the identical implementation of EN 250:2000 and is adopted with the permission of CEN, rue de Stassart 36, B-1050 Brussels. Published by Standards South Africa 1 dr lategan road groenkloof ! private b
5、ag x191 pretoria 0001 tel: 012 428 7911 fax: 012 344 1568 international code + 27 12 www.stansa.co.za Standards South Africa 2003 SANS 50250:2003 Edition 2 EN 250:2000 Edition 2 Table of changes Change No. Date Scope National foreword This South African standard was approved by National Committee ST
6、ANSA TC 5120.05, Vessels and systems under pressure, in accordance with procedures of Standards South Africa, in compliance with annex 3 of the WTO/TBT agreement. This standard is referenced in SANS 10019 (SABS 019), which, in turn, is referenced in the Vessels under Pressure Regulations of the Occu
7、pational, Health and Safety Act, 1993 (Act 85 of 1993). This SANS edition cancels and replaces the first SABS edition (SABS EN 250:1993). EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 250January 2000ICS 13.340.30 Supersedes EN 250:1993English versionRespiratory equipment - Open-circuit self-cont
8、ained compressedair diving apparatus - Requirements, testing, markingAppareils respiratoires - Appareils de plonge autonomes air comprim et circuit ouvert - Exigences, essai,marquageAtemgerte - Autonome Leichttauchgerte mit Druckluft -Anforderungen, Prfung, KennzeichnungThis European Standard was ap
9、proved by CEN on 7 November 1999.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationa
10、lstandards may be obtained on application to the Central Secretariat or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified
11、 to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and Unit
12、ed Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGCentral Secretariat: rue de Stassart, 36 B-1050 Brussels 2000 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN 250:2000 EPage
13、 2EN 250:2000ContentsForeword4Introduction .51 Scope52 Normative references53 Terms and Definitions.64 Description.74.1 General .74.2 Sub-assemblies .75 Requirements 85.1 Design.85.2 Materials.85.3 Air cylinder(s) 85.4 Cylinder valves 85.5 High pressure parts and connections.95.6 Demand regulator95.
14、7 Hose assemblies .105.8 Safety device115.9 Facepiece .135.10 Body harness.155.11 Resistance to temperature .155.12 Cleaning and disinfection.155.13 Practical performance test .156 Testing166.1 General .166.2 Visual inspection.166.3 High and medium pressure parts and connections 166.4 Pressure relie
15、f system 176.5 Demand regulator18Page 3EN 250:20006.6 Exhalation valve 186.7 Cylinder valve186.8 Facepiece.196.9 Safety devices .206.10 Resistance to specific temperatures.206.11 Practical performance test .217 Marking.228 Information supplied by the manufacturer.22Annex ZA (informative) Clauses of
16、this European Standard addressing essential requirements or otherprovisions of EU Directives .28Page 4EN 250:2000ForewordThis European Standard has been prepared by Technical Committee CEN/TC 79 “Respiratory protective devices“,the secretariat of which is held by DIN.This European Standard replaces
17、EN 250:1993.This European Standard shall be given the status of a national standard, either by publication of an identical text orby endorsement, at the latest by July 2000, and conflicting national standards shall be withdrawn at the latest byJuly 2000.This European Standard has been prepared under
18、 a mandate given to CEN by the European Commission and theEuropean Free Trade Association, and supports essential requirements of EU Directive(s).For relationship with EU Directive(s), see informative Annex ZA, which is an integral part of this standard.According to the CEN/CENELEC Internal Regulati
19、ons, the national standards organizations of the followingcountries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland,France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden,Switzerland and the United
20、Kingdom.Page 5EN 250:2000IntroductionA given self-contained open-circuit compressed air underwater breathing apparatus can only be approved when theindividual components satisfy the requirements of the test specification which may be a complete standard or part ofa standard, and practical performanc
21、e tests have been carried out successfully on complete apparatus wherespecified in the appropriate standard. If for any reason a complete apparatus is not tested then simulation of theapparatus is permitted provided the respiratory characteristics are similar to those of the complete apparatus.1 Sco
22、peThis European Standard applies to self-contained open-circuit compressed air underwater breathing apparatus andtheir sub-assemblies.The object of the requirements and tests set out in this European Standard is to ensure a minimum level of safeoperation for apparatus down to a maximum depth of 50 m
23、.Laboratory and practical performance tests are included for the assessment of compliance with the requirements.2 Normative referencesThis European Standard incorporates by dated or undated reference, provisions from other publications. Thesenormative references are cited at the appropriate places i
24、n the text and the publications are listed hereafter. Fordated references, subsequent amendments to or revisions of any of these publications apply to this EuropeanStandard only when incorporated in it by amendment or revision. For undated references the latest edition of thepublication referred to
25、applies.EN 132 Respiratory protective devices - Definitions of terms and pictogramsEN 144-1 Respiratory protective devices - Gas cylinder valves - Thread connection for insertconnectorEN 148-1 Respiratory protective devices - Threads for facepieces - Part 1: Standard threadconnectionEN 148-2 Respira
26、tory protective devices - Threads for facepieces - Part 2: Centre thread connectionEN 148-3 Respiratory protective devices - Threads for facepieces - Part 3: Thread connection M 45x3EN 12021 Respiratory protective devices - Compressed air for breathing apparatusISO 263 ISO inch screw threads - Gener
27、al plan and selection for screws, bolts and nuts - Diameterrange 0,06 to 6 inISO 5145 Cylinder valve outlets for gases and gas mixtures - Selection and dimensioningISO 12209-1 Gas cylinders - Outlet connections for gas cylinder valves for compressed breathable air -Part 1: Yoke type connectionsISO 1
28、2209-2 Gas cylinders - Outlet connections for gas cylinder valves for compressed breathable air -Part 2: Threaded connectionsISO 12209-3 Gas cylinders - Outlet connections for gas cylinder valves for compressed breathable air -Part 3: Adaptor for 230 bar valvesPage 6EN 250:20003 Terms and Definition
29、sFor the purposes of this European Standard the terms and definitions given in EN 132 and the following apply.3.1self-contained, open-circuit compressed air underwater breathing apparatus (SCUBA)apparatus which has a portable supply of compressed air carried by the diver, allowing him to breathe und
30、er waterand exhale into the ambient water.The SCUBA, when ready to use, consists of a number of compatible sub-assemblies each of which complies withthe appropriate requirements of this standard. When connected together, the complete SCUBA is designed toenable the wearer to breathe air on demand fro
31、m a high pressure cylinder (or cylinders) via a demand regulatorconnected to a facepiece. The exhaled air passes, without recirculation, from the demand regulator via theexhalation valve to ambient water.3.2high pressurepressure inside inside the air cylinder(s)3.3medium pressurepressure between the
32、 pressure reducer and the demand valve3.4low pressurepressure within the facepiece, approximately ambient pressure3.5rated working pressuremaximum working pressure of the respective components3.6reference pressureequilibrium pressure which exists in the facepiece when there is no respiratory gas flo
33、w3.7respiratory pressuredifferential pressure in the facepiece relative to the reference pressure measured during inhalation and exhalation3.8opening negative pressure (cracking pressure)respiratory pressure during inhalation required to open the inhalation valve3.9displaced (tidal) volumevolume of
34、breathing gas displaced by the breathing simulator during one half cycle (inhalation or exhalation)measured in litres3.10breathing frequencysetting of the breathing simulator measured in cycles per minute3.11respiratory minute volume (RMV)product of the tidal volume and breathing frequency measured
35、in litres per minute3.12pressure volume diagramdiagram generated during one breathing cycle by plotting the respiratory pressure against the displaced volumePage 7EN 250:20003.13work of breathingwork expended during one breathing cycle measured in J/l. This work is, in general, proportional to the a
36、reabounded by the pressure volume diagram. Work associated with positive pressures during inhalation does not counttowards the total work of breathing3.14facepiecedevice for connecting the apparatus to the wearer. It may be a mouthpiece assembly, a diving half mask or a fullface mask3.15mouthpiece a
37、ssemblydevice usually held by the teeth, sealing against the lips and through which air is inhaled and exhaled3.16full face maskfacepiece covering mouth, nose, eyes and chin which may be fitted with either a mouthpiece or an inner mask3.17diving half maskfacepiece, covering mouth and chin and retain
38、ed by straps3.18dead spacevolume of the cavity formed between the mouth and the inhalation and exhalation parts3.19package of air cylinder(s)consists of one or more air cylinders with cylinder valve(s) and a carrying frame (if applicable)3.20demand regulatorcontains a pressure reducer and a demand v
39、alve fitted to a facepiece3.21demand valvedevice, that forms part of a demand regulator which reduces the medium pressure air to ambient pressure3.22carrying systemcarrying frame or holding device for air cylinder(s) with possibility to mount the harness (if applicable)3.23pressure reducerdevice, th
40、at forms part of a demand regulator which reduces the high pressure air to medium pressure4 Description4.1 GeneralThe SCUBA may consist of subassemblies.4.2 Sub-assembliesDuring use the minimum sub-assemblies elements shall be the elements a) to e).a) air cylinder(s) with cylinder valve(s);b) demand
41、 regulator;Page 8EN 250:2000c) safety device (s);d) facepiece: mouthpiece assembly or a diving half mask or full face mask;e) carrying system.NOTE Each sub-assembly will be provided with information according to clause 8.5 Requirements5.1 DesignThe SCUBA and sub-assemblies shall be so designed that
42、its components are located so that protection isachieved against mechanical damage caused by external influence and that it is possible to perform the requiredpre-dive functional checks.The combination of sub-assemblies shall not adversely affect the safe operation and use of apparatus.In the case o
43、f several interconnected cylinders it shall be ensured that pressure equalisation between openedcylinder valves and/or open reserve valves is not impeded.The SCUBA and sub-assemblies shall not have any projecting parts or corners and edges which may injure thediver.All parts which have to be actuate
44、d by the diver during use shall be accessible and controllable even when wearingprotective gloves (3-finger, 6 mm to 7 mm, padding on either side). They shall be designed such that their settingcannot be altered inadvertently during use.Testing shall be done in accordance with 6.2 to 6.11.5.2 Materi
45、alsThe materials used shall have adequate mechanical strength and feature sufficient resistance to changes causedby the effect of temperature individually and in the assembled, ready-to-use SCUBA.Materials that may come into contact with the wearers skin and/or mouth shall not be known to be likely
46、to causeirritation or any other adverse effects to health.After testing in accordance with 6.2 and 6.11 the SCUBA shall still be fully functional, thus satisfying the specifiedrequirements.Testing shall be done in accordance with 6.2 and 6.11.5.3 Air cylinder(s)The air cylinder(s) shall comply with
47、the appropriate national or European specifications and shall be approved andtested with respect to the rated working pressure.The air cylinder shall be marked with the appropriate neck thread designation according to EN 144-1 where thepreferred versions are M 18 x 1,5 and M 25 x 2.Testing shall be
48、done in accordance with 6.2.5.4 Cylinder valvesCylinder valves shall comply with appropriate national or european specifications and shall be approved and testedfor use at the rated working pressure.The threads shall be as specified in EN 144-1 where the preferred versions are M 18 x 1,5 and M 25 x
49、2.Page 9EN 250:2000Safe connection between the cylinder valve(s) and the demand regulator shall be ensured by using one of theconnections specified in the following standards ;a) ISO 5145;b) ISO 12209-1, ISO 12209-2, ISO 12209-3.The valve shall be so designed or so located that it cannot be closed inadvertently. This is met e.g. by at least 2turns from fully open to fully closed position.The function of the cylinder valve shall not be impaired by the ingress of water.The cylinder valve shall be protected against the entrainment of dirt, solid particles and water from ins
