基本的电气安全(1).ppt

1,BasicElectricalSafety基本的电气安全PRODUCTIONTECHNICALTRAININGTEAM生产技术培训组,2,GeneralOpeningComments前言SubpartSoftheOSHAGeneralIndustryStandardscontainstheOSHArulesthatgovernelectricalsafety-relatedworkpractices.Withinthesestandards,OSHA29CFR1910.331-.335arerequirementsthatrelatetothetrainingof“Qualified”and“Unqualified”personsinelectricalsafeworkpractices.职业安全与卫生条例OSHA一般工业标准的S部分包含OSHA的规定，这些规定指导和管理与电气安全相关的工作实践。在这些标准中，OSHA29CFR1910.331.335对培训电气安全工作中的“合格”和“不合格”人员的培训提出了要求。AccordingtoOSHA,“Qualified”personsforthisfacilityareemployeesthatfunctionintheinstrumentandelectricalcraftsoftheMaintenanceDepartment.“Unqualified”persons,arethoseemployeeswho,intheirroutineworkduties,mayencounterarelativelyhighriskofinjuryduetoelectricalhazards.按OSHA的规定，工厂中的“合格”人员是指维修部门从事仪表和电气工艺的雇员，而“不合格”人员是指那些在履行他们的日常工作职责时相对容易受电气危险伤害的雇员。,3,Siteemployeessuchas,OperationsDcessunitpersonnel,MaintenanceDept.mechanicalcraftsandothermaintenancefieldpersonnel,laboratorytechnicians,andWarehousefieldpersonnelwouldbeconsideredbyOSHAtobeinthe“Unqualified”category.Inaddition,someEngineeringandTechnicaljobclassificationsbyassignmentordutiesmayalsobeconsideredinthe“Unqualified”categoryforpurposesofthistraining.现场的雇员，如生产部工艺装置人员、维修部机械专业和其它方面的维修人员、实验室技术人员和仓库方面的人员，在OSHA看来是属于“不合格”人员一类。另外，为培训的目的，被分配或从事设计和技术工作的人员也可以划入“不合格”人员一类。ThistrainingmodulehasbeenpreparedtoaddresstheOSHA29CFR1910.332requirementsfortrainingof“Unqualified”employeesinelectricalhazardsandworkpracticesnecessaryfortheirsafety.这个培训模块的编写是为了达到OSHA29CFR1910.332的要求，培训在电气危险和工作实践方面“不合格”的人员，以增强他们在安全方面的能力。Topicsincludetheeffectsofelectricalshockonthehumanbody,hazardsassociatedwithelectricity,localsourcesofelectricalhazard,causesofelectricalaccidents,protectivemeasurestopreventelectricalinjuries,andareviewoflocalplantpoliciesandproceduresthataddresselectricalsafety.下面介绍的内容包括：触电对人体的影响，有关电的危险，装置内的电气危险源，电气事故发生的原因，防止电气伤害的措施，以及SECCO关于电气安全方面的方针和程序。,4,INTRODUCTION引言Itiswellknownthatthehumanbodywillconductelectricity.Theelectricalcurrentflowsthroughthebodyandexitsattheothercontactpoint,usuallycalledtheground.众所周知，人体是导电的。电流流经人体后进入大地，对人体造成伤害的触电事故。Eachyearmanyworkerssuffersomeseriousinjuries,and/ordeathfromelectricshock.Itisestimatedthattherearemorethan1000electricalfatalitiesingeneralindustryeachyear,andover30,000injuries.Someadditionalstats:每年有许多工人因触电而受重伤或死亡。据估计，每年一般工业行业因触电死亡有1000多人，30000多人受伤。另外还有一些统计数字：99%ofthefatalitiesinvolvedmales.99%的死者是男性64%diedpriortotheageof35.64%的亡者死前年龄不到35岁。41%wereonthejoblessthan1year.41%的人参加工作还不到1年。1personiselectrocutedinthehomeevery25hrs.And1everydayatwork.人们在家里，平均25小时有1人触电死亡，而在工作时每天就有1人触电死亡Infact,electrocutionisconsideredtobethefifthleadingcauseofworkrelatedinjuryanddeath事实上，人们已经把触电死亡列为第5位因工作伤亡的原因。,5,TheEffectsOfElectricalShock触电的影响Theeffectsthatelectricshockwillhaveonanindividualwilldependuponthetypeofcircuit,itsvoltage,resistanceamperage,thepathwaythroughthebody,andthedurationofthecontact.Electricshockproducedbyalternatingcurrentsofpowerlinefrequency(normally50Hertz)passingfromhandtofootforonesecondcanproducethefollowingeffects:触电对人体产生的影响要视电路的类型，电压，电阻大小，电流流经人体的路线以及接触持续的时间而定。由电源线（通常为50赫兹）的交流电从手流到脚1秒钟的触电会产生以下的后果：milliamp-barelyperceptible1毫安刚能觉察到（手指麻刺）9-25milliamps-Interruptionofmuscularcontrol.925毫安对肌肉的自控中断（手迅速麻痹，呼吸困难）milliamps-interruptionofheartfunction75毫安心脏功能中断（心室开始颤动）amps-Immediatecardiacarrest4安培心搏立即停止,6,Nearlyinstantaneousfatalitiescanoccurfrom20milliampsorgreater.Eveniftheshockingcurrentdoesnotpassthroughvitalorgansornervecenters,severeinternalburnscanoccur,andinsomecasesinjuriessuchasthesecanbethecauseofdelayedfatalities.在电流强度为20毫安或以上时，就有可能会出现瞬间死亡。即使触电的电流没有流经致命的器官或神经中枢，也会出现体内的严重烧伤，在有时候，这样的烧伤会导致以后的死亡。Burnssufferedinelectricalaccidentsareofgreatconcern.Theseburnsmaybeofthreebasictypes:因电气事故引起的烧伤引起了人们的特别关注。这类烧伤有三种基本的类型：wElectricalburns电烧伤wArcburns电弧灼伤wThermalcontactburns热烫伤,7,Electricalburnsaretheresultofelectriccurrentpassingthroughbodytissuesandresultingdamageiscausedwhentheenergysourceheatissohighthatthebodycannotdissipateitandthetissueisburned.电烧伤是电流流经人体组织产生的结果，它造成对人体的伤害是因为当电能相当高时，人的身体无法把热量散发，将人体组织灼伤。Typically,suchelectricalburnsareslowtoheal.特别是这类电烧伤治愈是很慢的。Arcburns,ontheotherhand,aretheresultofhightemperaturesproducedbyelectricarcsoccuringclosetothebody.Theseburnsaresimilartotheburnsandblistersproducedbyanyhightemperaturesource.另一方面，电弧灼伤是离人体很近的电弧产生的高温造成的。这类烧伤与任何高温引起的烧伤和水泡相类似。,8,Finally,thermalcontactburnsarethosenormallyexperiencedfrommakingskincontactwithhotsurfacesofoverheatedelectricconductors,conduits,orotherenergizedequipment.最后，热烫伤通常是皮肤接触高温电导体、导管或其它带电设备的热表面所引起的。Itispossibleforavictimofelectricshocktoexperienceallthreetypesofburnssimultaneously.触电的人有可能同时受到这三种类型的烧伤。Secondaryinjuriesarefrequentlyassociatedwithelectricalshock.Theseinjuriesarenormallyassociatedwithfallsorcollisionsrelatedtotheelectricalshockcausinginvoluntarymusclereactions.Obviously,inthecaseoffallstheresultcanalsobefatal.触电还会经常引发二次伤害。这类伤害通常与因触电，引起肌肉不自觉的反射而跌倒或碰撞。显然，如果跌倒的话，也会引起死亡。,9,HAZARDSASSOCIATEDWITHELECTRICITY有关电的危险Ifanindividualcomesincontactwithanungroundedconductorwhiletheyareincontactwiththeground,theybecomepartofthecircuitandcurrentwillpassthroughtheirbody.若人们在触地时去接触未接地的导体，由于他们自己已成为电路的一个组成部分，电流就会流经他们的身体。引起触电。Inadditiontotheshockhazard,electricityposesotherhazardstopersonnel:除触电外，电对人体还有其它的危险：Arcing-arcingoccurswhenelectricityjumpsfromonepointtoanotherafterovercomingtheinsulatingcapacityofthesurroundingair.Thisconditioncancauseburninjuries,and/orstartfires.电弧电在克服了周围空气的绝缘电容后从一点跳到另一点就产生了电弧。这种情况能引起烧伤，和/或引起火灾。Fragmentation-extremelyhighenergyarcscandamageequipmentandcauseflyingmetalandothermaterialprojectiles.破碎能量极高的电弧能损坏设备，引起金属和其它材料四处飞射。,10,Flammableatmosphereexplosions-sparkingandarcingofelectricaltoolsandequipmentcanprovidethenecessaryignitionenergytocausefireand/orexplosionsinareasthatcontain,orpotentiallycontainhazardousatmospheres.可燃气体爆炸电气工具和设备发出的火花和电弧能提供起火和或爆炸所需的点火能量，当所在地区周围的空气中含有或潜在性地含有危险气体的话。Electricalhazardscanbefoundinelectricallydrivenmotors,electricalcontrolequipmentinmotorcontrolcenters,electricalpowergenerationanddistributionequipmentandinstallations,andoverheadpowerlines.电的危险还存在于电驱动的马达、动力控制中心的电控设备、发电和输配电设备和设施、以及架空的电源线等。Voltagesrangefrom220to220，000volts.电压范围在220到220，000伏。,11,NATUREOFELECTRICALACCIDENTS电气事故的性质Electricalaccidentsareusuallyrelatedtooneormoreofthreepossiblefactors:电气事故通常与以下可能的三种因素中的一种或几种有关：Workinvolvingunsafeequipmentand/orinstallations.工作所用的设备和/或设施不安全。Workmadeunsafebytheenvironment.周围环境造成工作不安全。（不安全的操作环境）Unsafeworkperformance(unsafeacts).工作进行不安全（不安全的操作）。OSHAhasestimatedfromstudiesitperformedthatapproximatelythree-fourthsofelectricalrelatedaccidentswerecausedbyunsafeworkpractices.职业安全与卫生条例管理局从所进行的研究中估算出大约有四分之三的电气事故是因操作不安全引起的。,12,Inadequatemaintenancecanresultinequipmentorinstallationswhichwereoriginallyconsideredsafetodeterioratetothepointthattheyposeanunsafecondition.Normallyunsafeelectricequipmentand/orinstallationscanbeidentifiedbythepresenceofwornorcrackedinsulation,looseconnections,orunguardedliveparts.疏于保养会使原来安全的设备或设施降到出现不安全的状态。通常，电气设备和/或设施的不安全可从绝缘的磨损或裂开、连接松动或带电的部件没有接地等来识别。Inanumberofwaystheworkenvironmentcanalsobeacontributingfactorinelectricalaccidents.Explosiveatmospheres,corrosiveatmospheres,wetand/ordamplocationsareexamplesofunsafeenvironmentsthatcanimpactelectricalsafety.工作的周围环境也有许多途径可能成为电气事故发生的原因。周围含可爆气体、腐蚀性气体、多雨和/或潮湿的位置都是影响电气安全的例子。,13,Unsafeactscantypicallyberecognizedasfailuretode-energizeelectricequipmentformaintenanceorrepairs,intentionaluseofobviouslydefectiveand/orunsafetools,ortheuseoftoolsorequipmenttooclosetoenergizedparts.典型的不安全操作的例子有：在保养或维修时不断开电气设备的电源，有意使用明显有故障和或不安全的工具，或使用的工具（设备）离带电部件太近。,14,PROTECTIVEMEASURES保护措施SECCOdesignandspecifyallelectricalinstallationscomplywithexistingcodesandpracticesasgovernedbyOSHA,theNationalElectricalCode,andinternalcorporatestandards.SECCO设计和规定所有的电气设备必须符合OSHA，全国电气规程和公司内部标准的现行规范和惯例。Theuseofproperinsulatingmaterials,guarding,and/orlocatingofelectricalequipmentisdonetoassureemployeeprotectionfromthehazardsofelectricitypresentatthisplant.合理使用绝缘材料、加强警卫、和/或为电气设备选择合适的位置，以保证雇员不受到工厂内的电气危险。However,eventhoughequipmentmaybeincompliancewithinstallationrequirements,employeesmaystillbeatriskofexposuretoelectricalhazardsifsafeworkpracticesandproceduresarenotfollowed.然而，即使设备符合安装要求，如果不按安全的工作惯例和规程去做，雇员仍有可能受到电气危险的威胁。,15,Suchworkpracticesincludekeepingaprescribedsafedistancefromexposedenergizedlines,avoidingtheunsafeuseofelectricalequipment,andfollowinglockout/tagoutprocedures.安全工作惯例包括：离开暴露的带电线路保持规定的安全距离，避免不安全使用电气设备，遵守锁定和/或掛牌程序。SECCOhaveimplementedmultiplesiteSafetyPoliciesandProcedurestoaddresssafeelectricalworkpractices.SECCO在电气安全操作方面贯彻了各种现场的安全方针和规程。Inadditiontothesewrittenpolicies,othergoodgeneralworkinformation,reminders,andpracticesforelectricalsafetyare:除了书面的规定外，还有以下常规的良好工作信息、提醒和电气安全方面其它的工作惯例：Priortousingportableelectricalequipment,carefullyinspectitfordefectssuchasfrayedordamagedinsulationorissingparts.Ifthereisaproblem,removetheequipmentfromervice,tagit,andnotifypropersupervisiontohaveitrepaired.在使用手提的电气设备前，仔细检查绝缘有无磨损、损坏、或部件有无缺损。若检查发现有问题，要把设备撤离工作线，做上标记，通知检查维修。,16,Portableelectricalequipmentshouldnotbepickeduporcarriedbyitspowercord.Alteringaplugorreceptacleorusinganadapterdesignedtooverridethegroundingconductorisdangerousanditshouldntbedone.手提式电气设备的电源线不能作提起或搬运用。改换插头或插座，或用适配器避开接地导体是很危险的，不能这样做。Routineopeningandclosingofcircuitsshouldbeaccomplishedwithswitches,interrupters,orcircuitbreakers.日常开、关电路要用电闸、断续器或断路器。,17,Ifacircuitisopenedbythetrippingofaprotectivedevicesuchasafuse,circuitbreakerorGFI,donotresetthecircuituntilyouhaveidentifiedandresolvedtheproblem.Insomecases,itmaybenecessaryfora“Qualified”persontoinvestigateandcorrectthesituation.Protectivedevicesinacircuitarethereforapurposeandarenottobedefeated,modified,orbypassedeventemporarily.若电路受熔丝、断路器或GFI等保护装置的跳闸而断开时，在找出原因和解决故障之前，不要重新接通电路。有时，可能需要请“合格的”人员到现场寻找原因并解决问题。电路中的保护装置在电路中都是有它的用途，不能使其失效、修改或被旁通，即使临时这样做也不行。Electricityhastheabilitytoarc,orjumpfromunguardedpowerlinestoanindividualincloseproximitytotheline.Quiteafewpeoplehavebeenkilledorinjuredwhilecarryingapieceofconductiveequipment,suchasaladder,inanelevatedpositionorbybeingincontactwithavehiclethatcomeswithinarcingrangeofanoverheadpowerline.电可产生电弧，或能从未保护的电源线跳到附近的人身上。不少人在高处扛着一个导电的设备（如梯子）走的时候，或接触了来自架空电源线电弧范围内的车辆，触到电源线的电弧而死亡或受伤。,18,Theminimumsafeapproachdistancefor“Unqualified”personstooverheadlineshasbeenestablishedat10feet.Theminimumsafeapproachdistanceforcraneboomshasbeensetat20feet.“不合格”人员离架空电源线的安全距离规定至少为10英尺（3m)。起重机吊架离开的安全距离规定至少为20英尺(6m)。Standardred,black,andwhite“DANGER”warningsignsaretobeusedtomarkhighvoltageelectricalinstallationstoalertemployeesofthepotentialelectricalhazardsastheadministrativemeansofhazardcontrol.Periodicinspectionsshouldbeperformedtoverifythatsignsorinplaceandingoodserviceablecondition.应采用标准的红、黑、白色的“危险”警示牌来标记高压电气设施，提醒雇员潜在的电气危险，作为控制危险的管理措施。对此要定期进行检查，确认这些标记在指定的地方，并处于良好的状态。,19,SUMMARY结论Whendealingwithelectricalequipmentandtoolsitisveryimportantweunderstandandfollowidentifiedgoodsafeworkpracticesinourdailyjobactivities.ThisisespeciallytruewithinSECCOwiththepresenceofthehighvoltagesrequiredtopowerprocessequipment.OSHA,throughtheissuanceoftheSubpartSelectricalsafetystandards,hasestablishedthecategoriesof“Qualified”and“Unqualified”personsintermsofelectricalworkknowledgeandtraining.在与电气设备和工具打交道时，很重要的一条是我们要知道并遵守日常工作中良好的安全工作惯例。这在SECCO范围内尤为如此，因这里需有高压电来开动工艺设备。职业安全与卫生条例管理局通过发布S部分电气安全标准，它根据人们的电气工作知识和培训的情况，规定了“合格”和“不合格”二类人员。,20,“Qualified”individua