nebosh questions & answers-gc2 new new new

7/21/2019 Nebosh Questions & Answers-GC2 New New New

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NEBOSHInternational General Certifcatein Occupational Health and Saety

Questions & Answers

Q! Identiythe controlmeasures needed to reduce the riskto workers (8)A12 The controlmeasures needed to reduce the risk to workersinclude:-the detection of underground services by using lans or

cable!ie detectorssuorting the sides of the e"cavation by shoring or benchingstoring materials and soil away from edge of the e"cavationroviding means to revent vehicles falling into the e"cavationsuch as sto blocksroviding guard-rails and barriers to revent eole falling intothe e"cavationroviding means of suort for ad#acent structures to reventcollase

roviding safe means of access!egress into the e"cavationtesting for no"ious fumes and roviding ventilation if necessaryusing ums to rotect against $oodingtaking recautions to safeguard the workers from biologicalha%ards or those caused by the resence of contaminatedgroundarranging for the e"cavation to be insected at regular intervalsby a cometent erson

Q!!Outline a hierarchy of measures for controlling e"osuresto ha%ardous substances& "#$A22 The various stages of the usual hierarchy of risk controlsare underlined in this answer&'limination or substitution is the best and most eective way ofavoiding a severe ha%ard and itsassociated risks& 'limination occurs when a rocess or activityis totally abandoned because theassociated risk is too high& ubstitution describes the use of aless ha%ardous form of the substance& There are manye"amles of substitution* such as the use of water-based rather
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continuing eectiveness& eriodically the risk control measuresshould be reviewed&3onitoring and other reorts are crucial for the review to beuseful& /eviews often take lace at

safety committee and!or at management meetings&A serious accident or incident should lead to an immediatereview of the risk control measures in lace&4inally* secial control reuirements are needed forcarcinogens&

Q% Outline ossible measures to minimise the risks to youngersons at work& (5)

A6 /isk assessment seci7c to young ersons+nduction trainingareful suervision by e"erienced and resonsible workerseci7c health surveillancelear lines of communication/estriction on tye of work and hours worked

Q# efne 9ergonomics (2)A1;&There are many accetable de7nitions:

The study of the interaction between workers and the workenvironment3aking the #ob or task 7t the erson

The study of how eole interact with machinery or euimentwithin the worklace'rgonomics is the alication of scienti7c informationconcerning humans to the design of ob#ects* systems andenvironment for human use4itting the #ob to the eole who have to do it* through thedesign of euiment and rocedures4itting the erson to the #ob* through the use of lacementrocedures or training

The study of how the worklace relates to human functions

Q' Identiy SI( observations of a machine oerators stationwhich could suggest that the machine has not beenergonomically designed& (


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3achine controls in awkward ositionsontrols unmarked or oorly marked and functions not obvious=ack of visibility by the oeratori%e or weight of work item making it di.cult to osition or

because of tye of machine rotection>i.culty in changing* ad#usting or cleaning machine tools

GC!) Control o International *or+place Ha,ards

-ast Questions & Answers ro. NEBOSH IGCE/a.inations

QIdentiythe factors that could lace a greater risk ofaccidents at work on young ersons& ?5@A1 =ack of knowledge* lack of e"erience* lack of training*hysical develoment of the individual* desire!nature of youngerson to take risks* eer grou ressurein young ersons isgenerally greater than that of more e"erienced individuals&

Q!Outlineossible measures to minimise the risks to youngersons at work& ?5@A2 arry out a young ersons risk assessment* comrehensiveinduction training* good suervision by e"erienced andresonsible emloyees* seci7c health surveillance* clear linesof communication* restriction on the variety of work * shiftatterns and number of hours worked&

Q0Identiyeight common causes of 7res in the worklace& ?8@A5 4aulty electrical euimentor incorrectly used electricaleuiment* smoking matrials discarded unsafely* oorlymaintained euiment ie friction caused by lack of lubrication*sarks from certain tyes of work eg grinding* hot surfaces onheating aliances* wilful intention to cause 7res ? arson@*statice electricity resulting from imroer transfer of $ammableliuids* certain chemical reactions can give o heat* hot workeg cutting B welding&Cote: lease remember to ay attention to the wording of theuestion ie D causes of 7resD is dierent from the sread of
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7resE* also + would urge you to ractice answering uestions inaragrah style unless you were asked to +dentify in which caseyou can +dentify or use bullet oint answers&

Q1Outline the ossible eects on health from e"osure tohigh levels of noise"2$&AF ossible eects on health from e"osure to high levels ofnoiseinclude:-both ermanent and chronic eectsnoiseinduced hearing loss(caused by damageto the hair cellsof the inner ear with reduced hearing caacity at articularfreuencies)tinnitusand temorary eects such as temorary threshold

shift* acute tinnitus* stress and fatigue&acute trauma such as a burst eardrum caused by e"osure tosudden loud noise

G< Outlinethe ha%ards that a worker could be e"osed towhen using a etrol driven chainsaw to cut down tree "2$A< 0a%ards from a etrol driven chainsaw include:-contact with moving arts of the chainsawe"osure to fumes and dust

ha%ards arising from manual handling oerationse"osure to noiseand vibrationfalls from heighthandling lubricating oils which might lead to dermatitis$ying articles such as tree bark and sawdustuneven ground or wet grass which could lead to slis and fallsfalling ob#ects such as branches or the tree itselfcontact with overhead servicesha%ards from adverse weather conditions

Q3 +dentify '+H0T common causes of 7res in the worklace (8)AI ommon causes of 7re in the worklace include:-faulty or incorrectly used electrical euimentmachinery or lant which has either incorrectly used or badlymaintained such as friction caused by inadeuate lubricationchemical reactions that may give o heathot work such as welding or cuttingsmoking materials which are discarded in an unsafe mannerhot surfaces such as those on cooking or heating aliancessarks from cold working such as grinding
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static electricity arising from the incorrect transfer of$ammable liuidsarson

Q2Outlinethe recautions that should be taken when usingmobile cranes "2$A8 recautions for the use of mobile cranes could include:-ensuring the crane and its attached lifting gear are suitable forthe taskthat the ground on which the crane is to be sited is $at and 7rmand that the outriggers of the crane are always correctlyositionedthat the driver and slinger to be used in the oeration are

cometentthat there are no obstructions such as overhead owerlines orbuildings in the vicinity of the lift and that warning signs andbarriers are erected to ensure that the area where the lift is totake lace is ket clear of ersonnel not directly involved in theliftthe actual lift should involve carrying the loadsmoothly at anaroriate height and ideally to an arranged lifting lan&

Q% Outlinethe controlmeasures that might be reuired inorder to minimise risks to workers& "2$A6 The controlmeasures that might be reuired in order tominimise risks to workers include:-use of suitable containers for the chemicals carrying warningsigns as to their dangerthe methods used for handling the chemicalsrocedures for the cleaning u and containment of the sillagesthe rovision of adeuate ventilation for the working areas andthe use of ersonal rotective euimentsuch as chemicalroof gloves* eye rotection and overallssite rules setting out the hygienerocedures to be followed androhibiting eating or smoking in the working areassetting u emergency rocedures including 7rst aidrovisionroviding emloyees with instruction* information and trainingon the handling of to"icsubstances and ensuring the rovisionof adeuate suervision and monitoring to check that controlmeasures were being followed&
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Q# '"cavation work is being carried out on a constructionsite& Identiythe controlmeasures needed to reduce the riskto workers"2$

A1; The controlmeasures needed to reduce the risk to workersinclude:-the detection of underground services by using lans orcable!ie detectors suorting the sides of the e"cavation byshoring or benchingstoring materials and soil away from edge of the e"cavationroviding means to revent vehicles falling into the e"cavationsuch as sto blocks roviding guard-rails and barriers torevent eole falling into the e"cavation

roviding means of suort for ad#acent structures to reventcollaseroviding safe means of access!egress into the e"cavationtesting for no"ious fumes and roviding ventilation if necessaryusing ums to rotect against $oodingtaking recautions to safeguard the workers from biologicalha%ards or those caused by the resence of contaminatedgroundarranging for the e"cavation to be insected at regular intervals

by a cometent erson

Q A glassworks roduces covers for streetlights andindustrial lighting& The rocess involves molten glass beingblown by hand and shaed in moulds&(i) Identiy4JK/ health eects that may be caused by workingin the hot conditions ofthe glass factory& (5)(ii) escri4emeasures that could be taken in order to

minimi%e the health eects of workingin such hot environments& (


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5& Murns from handling hot molten glassF& (Additional answer) the eyes can also be aected by highintensity light from looking at molten glass&(ii) The health eects of working in a hot environment can be

reduced by the gradual acclimati%ation of new workers& 'venafter the initial acclimati%ation* freuent rest eriods will benecessary to allow the body to acclimati%e to the hot conditionson a daily basis& /est should be in cool areas which in summermay need to be arti7cially cooled& +f* in addition* the humidity ishigh* a good suly of ventilation air will be needed* to helcontrol sweating& Adeuate suly of cold drinking water isessential to avoid dehydration&orkers in hot conditions should wear aroriate clothes*

which must be a comromise between lighter garments toromote evaoration of ersiration* and rotective clothes torevent burns& +t will be necessary to rovide rotective leatheror 7 re resistant arons and gloves* and aroriate eye andface rotection such as eye visors& Nisors may need to besulied with cooling air to kee eole cool and ermit roervision& creens could also be rovided to rotect workers fromradiant heat&eriodic health surveillance should be rovided& 4inally* workers

should be trained to recognise ill health aects on others&(iii) The task should be analysed in detail so that all asects ofmanual handling are covered including the use of mechanicalassistance& This will involve a manual handling risk assessment&

The number of eole involved and ersonal factors* such asage and health* should also be considered& A satisfactory bodyosture must be adoted with the feet 7rmly on the ground andslightly aart& To avoid work related uer limb disorders(/K=>) there should be no stooing or twisting of the trunk,it should not be necessary to reach uwards since this willlace additional stresses on the arms* back and shoulders& Thefurther the load is held or maniulated from the trunk* the moredi.cult it is to control and the greater the stress imosed onthe back& These risk factors are signi7cantly increased if severalof them are resent at the same time& The load should not becarried over e"cessive distances (greater than 1; m)& Thefreuency of lifting* and the vertical and hori%ontal distancesthe load needs to be carried (articularly if it has to be liftedfrom the ground and!or laced on a high shelf) can lead tofatigue and a greater risk of in#ury& +f the loads are handled


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whilst the individual is seated* the legs are not used duringlifting and stress is laced on the arms and back&

There should not be e"cessive ulling* ushing or suddenmovements of the load& The state of $oor surfaces and the

footwear of the individual should ensure that slis and tris areavoided&

There should be su.cient rest or recovery eriods and!or thechanging of tasks articularly in the hot ambient temeraturesof the glassworks& This enables the body to recover more easilyfrom strenuous activity&

The imosition of a high rate of work is a articular roblemwith some automated roduction lines and can be addressed bysells on other work away from the line&

The handling caability of an individual is aro"imately halvedwhen he or she becomes a member of a team& Nisibility*obstructions and the roughness of the ground must all beconsidered when team handling takes lace&

The load must also be carefully considered during theassessment O it may be too heavy& The ma"imum load that anindividual can lift will deend on the caability of the individualand the osition of the load relative to the body& There istherefore no safe load but guidance is available from 0'

literature* which does give some advice on loading levels& +f theload is too bulky or unwieldy* its handling is likely to ose a riskof in#ury& Nisibility around the load is imortant* as is awarenessthat it may hit obstructions or become unstable in windyconditions& The osition of the centre of gravity is imortant forstable lifting O it should be as close to the body as ossible,however* this may be di.cult if the load is hot* such as in bo"esor trays of recently blown glass& They should be allowed to coolsu.ciently&

The load becomes di.cult to gras when it is carried oversliery surfaces* has roundedcorners or there is a lack of foot room& ometimes the contentsof the load are likely to shift& This is a articular roblem whenthe load is a container full of smaller items* such as small glasscovers& These are glass comonents which may shatter ifdroed and leave shards of glass to be carefully cleared u&

The load is likely to be hot and could be shar as well in lacesor when broken so that ersonalrotective euiment* such as leather gloves and arons luseye rotection* may be reuired&


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Q! Outlinethe recautions that may be needed whencarrying out reairs to the $at roof of a building& (8)A12: /oof work is ha%ardous and reuires a seci7c risk

assessment and method statement rior to the commencementof work so that the reuired recautions may be identi7ed& Thearticular ha%ards are fragile roo7ng materials* including thosematerials which deteriorate and become more brittle with ageand e"osure to sunlight* e"osed edges* unsafe accesseuiment and falls& There must be suitable means of accesssuch as scaolding* ladders and crawling boards& uitable edgerotection will be needed in the form of guard rails to reventthe fall of eole or materials* and access must be restricted to

the area below the work using visiblebarriers& arning signs indicating that the roof is fragile* shouldbe dislayed at ground level& rotection should be rovided inthe form of covers where eole work near to fragile materialsand roof lights& The means of transorting materials to andfrom the roof may reuire netting under the roof and evenweather rotection&recautions will be reuired for other ha%ards associated withroof work* such as overhead services and obstructions* the use

of euiment such as gas cylinders and bitumen boilers andmanual handling&4inally* only trained and cometent ersons must be allowed towork on roofs and they must wear footwear having a good gri&+t is good ractice to ensure that a erson does not work aloneon a roof&

Q0 4or 'A0 of the following agents* outlinethe rincialhealth eects AC> identiya tyical worklace situation inwhich a erson might be e"osed:(i) carbon mono"ide (2)(ii) asbestos (2)(iii) legionella bacteria (2)(iv) heatitis virus& (2)

A1L:(i) arbon mono"ide is a colourless* tasteless and odourlessgas& +t causes headaches and breathlessness and at higherconcentrations unconsciousness and death& The most commonoccurrence of carbon mono"ide is in e"haust gas from a vehicle


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engine& orking in a vehicle reair garage without roerventilation to e"haust gases would e"ose a erson to carbonmono"ide fumes&(ii) Asbestos roduces 7ne 7bres which can become lodged in

the lungs& This can lead to asbestosis (scaring of the lungs)*lung cancer or mesothelioma O cancer of the lining of the lung&Asbestos can be found in buildings* in ceiling tiles and aslagging around heating ies& hen these sites are disturbed*the asbestos 7bres become airborne and inhalable aectingthose engaged in maintenance or demolition work&(iii) =egionella is an airborne bacterium and is found in a varietyof warm water sources between 2; and 5FP& +t roduces aform of neumonia caused by the bacteria enetrating the

alveoli in the lungs&The disease is known as =egionnaires disease and hassymtoms similar to in$uen%a& The threemost common systems at risk from the bacteria are watersystems that incororate a cooling tower* air conditioning units*and showers& eole working on these systems or working inthe area of infected systems are at risk* articularly if they areover 5F years of age and it aects men more than women&(iv) 0eatitis is a disease of the liver and can cause high

temeratures* nausea* #aundice and liverfailure& The virus can be transmitted from infected faeces(0eatitis A) or by infected blood (0eatitis M and )& 0ositalworkers and 7rst aiders who come into contact with bloodroducts are at risk of heatitis&

-ractice Questions & Answers ro. NEBOSH IGCE/a.inations

Q '"cessive dust levels have been discovered in a worklace*the rincial cause being the ine.cient local e"haustventilation system (='N)& Identiy 4JK/ indications that couldhave highlighted the ='N systems ine.ciency& (5)A1 >eosits of dust on surfaces and eoleNisible articles in the air>iscomfort and irritation by emloyeesAir monitoring reviewsActual ill-health in emloyees due to e"osure to dusts


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Q! Outline the factors which could have reduced the ='Nsystems eectiveness& (8)A2 oor design=ack of lanned testing

=ack of maintenance'"traction hood too far from dust source>amaged or blocked ducting or 7ltersystem alterations O unauthori%edettings incorrect4aulty fanrocess changes that could lead to greater dust emissions&

Q0 escri4e other methods of control to minimise levels of

airborne dust e"cet from ='N& (8)AL 0ierarchy of control'liminating the rocess causing the dustA change in rocess to reduce dust amountsubstitution of materials i&e& casule form* ellets or liuidegregation or enclosure of the dust creation rocess>aming down the dust for easier removal such as vacuuming3ethods of cleaning so as not to disturb the dust i&e&vacuuming instead of sweeing

Q5 Outline necessary recautions to be taken whenedestrians are reuired to work close to vehicle movementareas& (8)A5 egregation systems for vehicles and edestrianslear and aroriate road markingsNisibility O mirrors* transarent doors* adeuate lighting etc&Nehicular audible warningsite rules0igh-visibility clothingHood housekeeing

Training and suervision of all involved on site

Q1 4actory cleaning sta use a rotary $oor olisher each night&Identiy the associated ha%ards& (5)AF 'ntanglementlis* tris and fallsCoiseNibration'lectrical ha%ards


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'rgonomic ha%ardsossible chemical involvement of cleaning agents

Q6 Outline what control measures could be used to reduce the

risks& (5)A< Huardingable management+solation for the task of changing brushesAroriate non-sli footwear/egular testing and maintenance/esidual current devices O />s

Training to ensure re-use checks

Q3 Outline recautions needed when maintenance work isbeing carried out in an underground storage vessel& (8)AI ermit-to-work/isk assessment+solationre-cleaningurging and testing the vessels atmoshereafe means of access and egressAroriate tools i&e& non-sark

&&'Aroriate lightingontinual monitoringometent and trained ersonnelHood communication systems between tank and above-groundworkers3aintenance of detailed emergency rocedures

Q2 Outline the rincial reuirements to ensure e"cavationwork is carried out safely&(8)A8 '"amine the suort structures weekly by cometenterson/ecord e"amination+nsect working art daily or er shift if deeer than 2m+nsect suort material before useuort work done under suervision of cometent ersonCo erson to work in e"cavation unless cometently e"aminedCo ro#ecting nails on suort structureCo materials left near edges of e"cavation


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Q%ith resect to work-related uer limb disorders(/K=>s)& Identiy tyical symtoms& (5)A6 Mack* neck and shoulder ainwollen #oints

/educed mobility and stinessrams and muscle fatigue!tiredness

Q# Outline the factors that would increase the develomentof /K=>s& (5)A1; >islay screen euiment issues O >'=ayout of workstation+nsu.cient breaks from the task+nadeuate sace leading to oor ostures

'"cessive force needed to carry out tasks4reuency of the taskNibrating tools!euimentre-e"isting medical conditionsregnant women

Q Outline what is reuired for a safe means of escae whenevacuating a building in the event of 7re& (8)A11 At least two escae routes in oosite directions7 none to

e"ceed the recognised travel distance'scae route 7re integrityelf closing 7re doors that oen outwards easily'scae routes clearly marked'mergency lighting for routes/outes ket free from obstructionafe* clearly signed assembly ointQ! hat are the rincial ha%ards associated with the use ofladders at workQ (L)A12 oor maintenance+ncorrect use+ncorrect locations

Q0 E/plainhow these ha%ards may be eliminated or reduced&(F)

A1L +nsection and reairorrect storageIF degrees sloe (1 in 5)ecured to and baseCot to use aluminium ladders near overhead cables


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Q5 Outline the recautions to rotect against electrocutionwhen e"cavating near underground cables (5)A15 uly isolation

able routes identi7cation via lans and cable detectorshecking for service bo" covers3arking of cable routes>igging with hand-tools

Q1 Outline the recautions to rotect against electrocutionwhen working near overhead ower lines (5)A1F +solationHoal-ost barriers de7ning clearance distances

Kse of signs and bunting to clearly mark danger %onesafe access routes under linesKse of marshals and banksmen when cranes* e"cavators ortier lorries may aroach/estriction on use of metal ladders and scaold tubes

Q6 Identiy '+H0Troutine insection items included on acheck+dentify at the beginning of a shift* before using a fork-lifttruck& (8)

A1< Tyre ressure and condition=ights functioning (where 7tted)ecure and roerly ad#usted seatsKndamaged mirrors with good vision=eakages from various $uids O diesel* battery acid* oil* brake$uid etc&Mattery connectionshains in good order0orn oerates/eversing audible signals where 7tted4orks in good orderMreak checks* including hand break4orks do not dro when raised O hydraulic $uid levels okCo lay in steering wheel

Q3 Outline '+H0Trecautions that should be considered torevent in#uries to children who may be temted to access aconstruction site& (8)A1I 4encingarning signs of any dangers


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ecurity atrolsTN+solating services/educing heights of materials

overing e"cavations/emoving ladders O lashing the ladders O to deny access toscaoldingecuring tools* chemicals* euiment and vehicles under lockand keyommunity liaisons

Q2 efne 9ergonomics& (2)A18 The study of the interaction between workers and their

work* and is concerned with the design of the worklace* workeuiment and work methods with the needs and limitations ofthe human oerator in mind&

Q% Outline which health issues could be caused by oorergonomic designs of dislay screen euiment (>')workstations& (5)A16 ork-related uer limb disorders such as: ain inshoulders* arms (including forearms)* wrists* hands* 7ngers and

even neck ains&'ye strainThis uestion asks for an outline which would tyically includedetail of the symtoms and the circumstances that would makethe eects more likely&

Q!# Outline which factors should be considered for anergonomic assessment of a >' workstation&(15)A2; 'uiment'nvironment

Task+ndividual -inter-relationshis between these four/eetitionorking osture of 7ngers* hands and wristsorking osture of shoulders and armssychosocial factors such as: ace of work* unlannedovertime!shift work* little control over own work* stressfuldeadlines*lack of training


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Q! Kseescri4ees to clearly show what is meant by thefollowing terms relating to mechanical ha%ards from movingarts of machinery&'ntanglement (2)

rushing (2)>rawing-in (2)hear (2)A! Co need for a masteriece& lear reresentation ofmachinery arts demonstrating each articular ha%ard& Arrowsto show the direction of movement


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Q!! Outline the main considerations when deciding on thesiting of 7re e"tinguishers& (5)A22 AccessibilityNisibilityro"imity to e"its and escae routes

Travel distancesuort of the euiment o the ground4ree from obstruction

rotection from the weatherrotection from other sources of damage


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Q!0 Outline maintenance and insection reuirements for 7ree"tinguishers& (5)+nsection O routine i&e& monthly visual checks ensuring

e"tinguishers are in lace* have not been discharged and haveno obvious damage&3aintenance8 annual tests by a cometent erson accordingto the manufacturers instructions in order to ensure thee"tinguishers integrity* with faulty euiment being removedand relaced&

Q!5 E/plain these terms with regards to noise control&ilencing (2)

Absortion (2)>aming (2)+solation (2)A25:Silencin9

The suression of noise generated by the air $ow* gas orsteam in ducts and ies* or when e"hausted to theatmoshere* and uses either absortive material or baResA4sorption

/eduction of re$ected noise by using materials such as foam ormineral woola.pin9/eduction of amount of noise radiating from large anels and iseected by increasing the stiness of the anelsIsolationhysical searation of eole from the noise source such asacoustic booths or havens* or by isolating the noise by vibrationusing $e"ible ies or anti-vibration machine mounts

Q!1 Outline a rocedure for the safe lifting of a load whilstusing a crane* ensuring the crane has been roerly selectedand ositioned for the task& (8)A2F The suitability of the lifting tackle such as its safe workingload* free from defects* etc&

The cometence of the eole involved i&e& driver* slinger*signaler

The load must be lifted vertically* secure balanced andcontrolled during the lift by the use of tag lines whenevernecessary


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roer communicationArea must be ket clear of non-essential ersonnel=ifting* moving and lowering must be erformed at the correctrate maintaining roer control at each art of the oeration

Q!6 efne the occuational health term Starget organ&(2)

A2< A art of the body that sustains an adverse eect whene"osed to* or is contaminated by* a articular substance oragent& The harmful eects of a to"ic substance con7ned toarticular organs such as the lungs* liver* skin or kidneys&

Q!3 Outline ersonal hygiene methods that would decrease

the risk of ingesting a ha%ardous substance& (


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ystem not overloaded

Q0# Outline the main recautions to be taken whilstundertaking an e"cavation ro#ect& (8)

AL; >etection of services using lans* cable!ie detectors etc&uorting the sidestorage of materials and soil away from the edge3easures to revent vehicles falling into e"cavations such assto blocksHuard rails and barriers3easures to revent collase of ad#acent structuresafe means of access!egress

Testing for* and ventilation of* no"ious fumes

3easures to um out waterafe rocedures for working with mechanical lant+nsection* training and suervision

Q0StateTJasbestos related resiratory diseases& (2)AL1 3esotheliomaAsbestosis=ung cancer

Q0! Identiy where you are likely to encounter asbestos in abuilding undergoing renovation work& (


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3echanical failure

:e;ision Questions & Answers ro. NEBOSH IGC

E/a.inations

Ele.ent


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U kee records: record the training undertaken by individualoerators and certi7cation awardedalong with continuous assessment and test resultsU authorisation: rovide written authorisation to those allowed

to oerate lift trucks&U monitor erformance:V kee an eye on oerating rocedures etcU refresher training: rovide as and when necessaryU health surveillance: rovide routine medical checks for lifttruck oerators* articularly for thosein middle age and above

Q!roduce a check-+dentify of key oints for the design and

layout of vehicle tra.c routes&A2 >esign and layout of vehicle tra.c routes* check+dentify ofkey oints:U ensure roadways are wide enough for the largest vehiclelikely to use them&U take account of the ma"imum number of vehicles andedestrians entering or leaving theremises at the beginning and end of each shift&U design road systems to rovide minimum travel distances

between laces where vehicles have to visit&U where ossible eliminate the need for vehicles to reverse by*for e"amle* the introduction ofone-way tra.c systems&U where ossible eliminate shar bends and blind corners,where this is not ossible rovidesuitable warning signs and mirrorsU kee road #unctions and rail crossings to a minimumU ensure entrances and gangways are wide enough to rovidesu.cient sace to accommodatevehicles stoed for checking from causing obstructionsU ensure there are clear direction signs and identi7cationmarkings on doors and buildings to hel avoid driver error andunnecessary tra.c movement

Q0>itto* a check-+dentify of the key oints for edestriantra.c routes&AL edestrian routes need to be ket clear and unobstructed&

The following key oints* outlined


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in the free 0' ublication J.cewise (+C>H1IL)* are worthstressing with regard to edestriantra.c routes:U do not allow trailing leads to create triing ha%ards

U do clear u sillages uicklyU do relace or reair torn $oor coverings etcU do rovide handrails on stairways and ensure stairs are welllitU do not block assageways or corridorsJbviously* the above recautions refer to 9in the o.ce,management must also ensure thatrisk assessments also e"tend to encomass:U edestrian routes into and out of the building: do doors

9suddenly oen on to avements*or on to vehicle routesU car arking arrangements* and so on

Q5 Outlinethe most imortant general reuirementsconcerning the conditions of $oors andtra.c routes&A5 Heneral reuirements concerning the conditions of $oorsand tra.c routes:

U sound constructionU su.cient strength and stability to meet the reuired demandsU surfaces should be even and free of faultsU secial attention must be aid to surfaces which are liable tobecome sliery* for e"amlein a machine sho with its oils and lubricants, in such anenvironment* $oors should benon-sli and every eort should be made to contain theinevitable sills by mounting themachines in 9trays and carefully designing the system of iesand valves by which themachines can be drained of coolant oils and other $uidsU when any sills or a leakages do occur* they should becleaned u immediatelyU $oors and tra.c routes which are oen to the elementsshould have 9non-skating rinksurfaces which may need to be gritted in sells of free%ingweather


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Q1eole and vehicles* what are the key reuirements of Theorklace /egulationsQAF eole and vehicles* reuirements of The orklace/egulations:

U searation of edestrians and vehiclesU careful design of crossing lacesU signosting and the use of $oor markings to indicate routes tobe followed by internalvehiclesU 9restraining barriers at sites where edestrain routessuddenly emerge onto vehicle routesU doors and gatesV use of transarent viewing anels

V safety features with ower-oerated doorsV safe use of uward oening doorsU consideration to be given to disabled eoleU suitabililty of routes used by vehiclesU signosting of restrictions (headroom* resence ofedestrians* sloes* blind bends andso on)U shielding and marking of dangerous obstructions such asoverhead electrical cables or

ieworkU rotection of illars and iework from imact by vehicles(fork-lift trucks are very heavy -the author once saw such a truck drive into a set of storageracking at a snails ace* butstill causing an ama%ing amount of damage)

Q6hat are the three main tyes of ha%ard faced byedestriansQA< lis* tris and falls, collisions, in#ury or damage caused byenvironmental conditions&

Q3hat are the main ha%ards causing slis* tris and falls onthe same levelQAI et or greasy $oors* uneven or loose surfaces* andobstacles on the surface&

Q2hat are the four main environmental ha%ardsQA8 =ighting levels* heat* noise and air uality&


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Q% Statefour items that a risk assessment should consider inrelation to otential ha%ards to edestrians&A6 There are many such factors& The following were given inthe unit:

W The normal atterns of movement in and around theworklaceW atterns of movement outside of those which are normal*whether authorised or not* and which may be reasonablyredictedW The articular needs of certain grousW The needs of eole not normally on the remisesW The in$uence of dierent weather conditionsW The in$uence of maintenance rocedures

W Accident and incident reortsW 0ow good are the e"isting measures and systems of work inroviding adeuate rotection for edestrians&

Q#hat is a designated walkwayQ(F) >esignated walkways are areas which are seciallyrotected from ha%ards by segregating eole from vehicles*and within which edestrians should be reasonably safe fromharm&

Qhere and how should ha%ard warning markings belacedQ(


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A1L =oss of control* overturning and collisions with othervehicles* edestrians or 7"ed ob#ects

Q5hat may cause loss of control of a vehicleQ

A15 >river error* mechanical failure and environmentalconditions&

Q1hat factors may contribute to the risk of overturningQA1F everal factors may be involved* including:W eed of travelW teeness of the sloeW 0eight of the vehicle (including its load)- tability of the loadW 0igh tyre ressureW Any e"ternal longitudinal ressure* such as wind or collidingob#ectsW resence and si%e of any bums or holes in the surface&

Q6 Identiythe environmental conditions which mightcontribute to accidents&A1< Adverse environmental conditions include:W oor weatherW oor lighting&

W oor sight lines&W oor ground surface&W ongestion&

Q30ow can visibility be imrovedQA1I My ensuring adeuate lighting is rovided for the tra.croute (and its surroundings)* and by making sure that sightlines are good&

Q2 Identiythe main safety measures used to managevehicle oerations and movement&A18 3anagement of vehicle oerations and movementsincludes the following measures:W 3ovement systemsW eed limitsW Nehicle arkingW igns and markingsW ignalling

W =oading and unloading roceduresW ecial rules for articular sites


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W Heneral rules to make sure vehicles do not become ha%ards&

Q%Jn what key areas should vehicle safety maintenanceconcentrateQ

A16 Nehicle safety maintenance should concentrate on:W Mraking systemsW teering mechanismsW TyresW '"haust systems&

Q!#+n what conditions should warning lights and alarmsystems be usedQA2; arning lights and alarms should be used to alertedestrians and other drivers of the aroach of a vehicle&

They are articularly imortant at blind corners* #unctions anddoorways* and on reversing&

Q!hat secial euiment should be 7tted to vehicles torotect driversQA21 The main methods of rotecting drivers are the use of seatbelts* secured doors and rotective cages and cabins withshatter-roof glass&

Q!!hat are the main means of searating vehicles andedestriansQA22 There are three main means of searation:W Marriers and!or clear surface markings to mark searateroutes for edestrians and vehicles&W >esignated crossing oints for edestrians to use whencrossing vehicle routes&W earate doorways* etc&* for edestrians&

Ele.ent !


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+f you are not able to illuminate each of these with a coule ofe"amles* refer back to the studymaterial&

Q!ho might be resonsible for the manual handlingassessment in a articular worklaceQA2 /esonsibility for conducting a manual handlingassessment: the answer to this uestion is the same generalanswer we always give when we consider who is able toundertake a articular risk assessment in a articularworklace* namely the erson(s) who searately or togetherhave a thorough knowledge of the work activities in uestion& +fno such erson(s) are available* then serious uestions must be

raised concerning both the working ractices and the trainingsta have received& '"cetions to this reuirement that in-house sta should be able to undertake the necessary riskassessments will arise with secialised euiment such assteam boilers and certain lifting euiment where outsidee"ertise (erhas rovided by insurance comanies) may beneeded& +n the +H2!2 study material we outlined the seci7cin-house e"ertise that might be called uon in a manualhandling assessment&

Q0auses of manual handling accidents and common manualhandling in#uries - together thebasis of many C'MJ0 uestions over the years* generally notdi.cult and one that shouldreward you with good marks& Accordingly* rovide an answer &&&AL auses of manual handling accidents and in#uries:U slis* tris and fallsU oor lifting techniuesU loads which are too heavy for the individual concernedU loads with shar cornersU decetive loads: either because they are une"ectedly heavyor because the centre of gravity is not as anticiatedU oor ostureU reeated handling and maniulation of loads which might beaccetable as a 9one-o&ommon in#uries include:U strains and muscle in#uries involving the sineU strains and muscle in#uries involving other arts of the bodyU scratches* bruising and gra%es (mostly to the uer body)


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U fractures* either as a result of falls or droing heavy ob#ectsonto the bodyJther common manual handling uestions ask the candidate to+dentify grous of workers who are

articularly at risk when it comes to manual handling in#uries& Agood answer will suly* erhas* four or 7ve at-risk groustogether with a brief outline of work they undertake and thein#uries likely to be encountered&

Q5 Outlinesome other general oints concerning manualhandling techniuesA5 Additional manual handling techniues include:U using a midway stage which may* for e"amle* be valuable

when an ob#ect has to be liftedfrom the $oor to a high shelfU making use of the strong leg muscles to ush an ob#ect into(storage) ositionU team handling - using two eole in certain manual handlingoerationsU ensuring that workers are aware of the most e.cient ways ofmanoeuvring euiment such astrolleys

U avoiding unnecessary stretchingU use of 9kinetic handling techniues

Q1 E/plain* giving a few details* how avoiding the need for aarticular manualhandling oeration can be achieved by: elimination of handling*or if this is not ossible*automation&AF Avoiding the need for a articular oeration &&&'limination of handlingU are certain handling oerations necessaryQU can the same results be achieved another wayQU can a rocess such as machining or wraing be carried outin situ* without handling theloadQ Automation or mechanisation* if the load handlingoerations cannot be avoided entirely:U can the oeration be mechanised - for e"amle* the use ofroller conveyorsU is automation a ossibilityQ


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Q6Knder the following motion of machinery ha%ard categories(+H2!L)* 9i;esome e"amlesof ha%ards seci7cally associated with handling euiment:U entanglement

U friction and abrasionU cuttingU shearU stabbing and unctureU imactU crushingU drawing inA< 0andling machinery ha%ards* some e"amles:U entanglement: rollers on conveyor systems* drum and cable

lifting dveicesU friction and abrasion: any handling system involving belts(very tough* very abrasive) for themovement of grain* coal* sand, simle building site roe andulley systemsU cutting: hard to think of a seci7c handling cutting e"amle*aart from the side edge of atravelling conveyor belt* although obviously many of the othercategories included here might

also involve cuttingU shear: lift moving across the oening in a lift shaft, any liftingeuiment that makes use ofscissor-actionU stabbing and uncture: any fast moving handling euimentmight* either on its own* orthrough the articles being carried cause this tye of in#uryU imact: clearly #ust about any moving handling euimentcould cause an imact in#ury (9tra.c ha%ards* +H2!1), weshould also mention the imact eects of euiment such asfork-lift trucks hitting storage racking* brick walls and so on -the damage that can be caused by evena very slow moving vehicle can be uite remarkable: bucklingand toling storage racks andso onU crushing: device such as an insection latform ushes theworker on the latform into theceiling* ventilation ducting etcU drawing in: roller and screw conveyor systems for movingbulk materials


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Q3+n addition to the motion of machinery ha%ards of therevious uestion* outlinesome otherha%ards associated with handling euiment&

AI Jther ha%ards associated with handling euimentU electrical ha%ards from the owerful batteries used in milk$oats* hand-oerated trucks etcU falls from heightU toling over of lifting euiment (you should be able tosuggest a few ossible causes)U electrostatic eects leading to 7re and e"losion ha%ards(think conveyor systems with thebuild-u of dust* frictional generation of electrostatic charges

etc)

Q2hat are the main causes of in#ury to workers as a result ofmanual handling oerationsQA8 The main causes of in#ury are:W 4ailing to use a roer techniue for lifting and!or moving theob#ect(s) or loadW 3oving loads which are too heavyW 4ailing to gri the ob#ect(s) or load in a safe manner

W Cot wearing aroriate ersonal rotective euiment&Q%hat is a /K=> and how might it be brought aboutQA6 /K=> stands for Swork related uer limb disorder andrefers to ill-health conditions aecting the uer limbs*articularly the soft connecting tissues* muscles and nerves ofthe hand* wrist* arm and shoulder&/K=>s arise from the reetition of ordinary movements (suchas griing* twisting* reaching or moving)* often in a forcefuland awkward manner* without su.cient rest or recovery time&

Q#hat is the rimary means of minimising the ha%ards ofmanual handlingQA1; The elimination of risk by the use of mechanical aids&

Qhat are the characteristics of the load which mayresent a ha%ardQA11 The characteristics of a load which constitute a ha%ard areits weight* si%e* shae* resistance to movement* rigidity or lack

of it* osition of its centre of gravity* resence or absence of


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handles* surface te"ture* stability of any contents and thecontents themselves&

Q! Identiythe main ha%ards resented by the working

environment in relation to manual handling oerations&A12 The main ha%ards in the working environment are:W /estrictions on movement and ostureW onditions of $oors and other surfacesW Nariations in levelsW Temerature and humidityW trong air movementsW =ighting conditions&

Q00ow can manual handling tasks be re-designed to make

them less ha%ardousQA1L /e-design of the task may include:W euencing O ad#usting the seuence of tasks in a rocess tominimise the number of oerations involving lifting andcarrying loads&W ork routine O reducing reetitive oerations to allowvariation in movement and osture* by such means asintroducing breaks* #ob rotation and roviding ways in whichworkers can oerate more at their own ace* rather than the

work being controlled by a continuous suly of materials to behandled&W Ksing teams O sharing the load by using teams of workers tocarry out the task&

Q5hat are the most common ha%ards associated with:(i) 4ork-lift trucks(ii) =ifts and hoists(iii) ranes

(iv) ack trucksQ

A15(i) The most common ha%ard of lift trucks is that* with theirsmall wheels and articularly when loaded and with the forksraised* they may become unbalanced* resulting in themshedding their load or tiing over& Jther ha%ards arise fromthe constant needto reverse the truck* obscured vision when the load is raised

and using unsuitable trucks for the working environment&


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(ii) The main risks associated with lifts and hoists are falls froma height (from a landing level* from the latform or with thelatform) and being hit by materials falling from the latform&Jther ha%ards include being struck by the latform or other

moving arts* and being struck by e"ternal ob#ects orstructures while riding on the latform&(iii) The main ha%ards associated with cranes are the risk ofthem becoming unbalanced and toling over* the arm of thecrane swinging out of control or the load striking somethingwhilst being moved hori%ontally or falling&(iv) The main ha%ards of sack trucks are overloading* instabilityof the load* tiing when moving over uneven ground or onsloes* and careless stowage&

Q1 hat ersonal rotective euiment might be aroriatefor working with:(i) allet trucks(ii) ranesQA1F(i) afety footwear* as well as gloves and arons to rotectwhilst handling loads&(ii) afety helmets&

Q60ow can entry to and e"it from lifts be made safe foreoleQA1< The main means of rotection is the use of interlockinggates which ensure that access to and egress from the liftlatform is only ossible when the lift is at rest& Jther relevantsafety measures include the ositioning of the oerator so thateach access oint can be seen or the use of signallers to informthe oerator that it is clear&

Ele.ent 0 *or+ e>uip.ent ha,ards and control

Q0ow is work euiment de7ned* give some e"amles&A1 ork 'uiment is de7ned as what is and what isnt workeuiment& Although you robably think that this answer is alittle evasive* such a statement should form art of your answertogether with some e"amles which fall within the de7nition ofwork euiment: lawn-mower* hotocoier* hand saw and somee"amles which fall outside the


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de7nition of work euiment: livestock* substances* structuralfeatures such as walls&

Q! escri4e* giving e"amles* what is meant by 9mobile work

euiment* 3'&A2 3' includes any euiment which carries out work whilstit is travelling (dumer* fork lift truck* cro srayer) or whichtravels between dierent locations where it is used to carry outwork (comressor* trench diggers* mobile latform forinsecting street lights)&

Q0Mrie$y outlinesome of the legal reuirements which alyseci7cally to 3'&

AL Co emloyee shall be carried on 3' unless it is suitableand incororates features to revent ersons falling underwheels and tracks& /oll-over rotection &&&reventing unauthorised start-u, starting* stoing*emergency stoing, drivers 7eld of vision,lighting for use in the dark, carriage of 7re aliances and soon*/emote ! robotic controlled self-roelled work euiment muststo automatically if it leaves its control range and risks of

crushing and imact must be guarded against&rotection against the ha%ards associated with the transmittingower from one iece of workeuiment to another* for e"amle the ower take-o shaftfrom a tractor to a hay baler&

Q5+n develoing a training rogramme which will satisfy theneeds of legal reuirements* three articular asects of workwill need to be addressed - what are theyQA5 The three asects of work that will need to be encomassedin a training rogramme will be:U day to day oeration of the euiment - starting* stoing*loading* unloading and so onU foreseeable abnormal situations such as a drill bit shatteringor a tyre uncturingU what the 0' describe as 9conclusions to be drawn frome"erience in using the work euiment which means that*following training* the worker should have su.cient knowledgeto be able to make constructive criticism about the euimentand its use in the worklace in uestion&


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Q1hen develoing the training rogramme* what factors willneed to be considered as far asthe needs of individual workers are concernedQ

AF +t will be necessary to consider the emloyees age ande"isting cometence and hence what additional training will benecessary to enable them to use* suervise or manage the useof the work euiment with due regard to health and safety& (+tis imortant to remember that an emloyer has an obligation totrain not only to those who use work euiment but also tothosesuervising or managing&)

The training rogramme should also take account of the

circumstances in which the emloyee is to work (alone* underclose suervision of a cometent erson or whatever)&

Q60ow can you de7ne the motion of machinery artsQA< 3achinery motion may be described as being a combinationof rotary and linear motion, (recirocating movement can beseen as a form of linear motion)&

Q3There are various dierent ways of classifying the

mechanical ha%ards associated withmachinery motion, in our study material we have chosen to usea common classi7cationwhich divides mechanical ha%ards in eight categories, the 7rstis entanglement* can youIdentiythe other sevenQAI The mechanical ha%ards associated with machinery motionmay be classi7ed as follows:U entanglementU friction or abrasionU cuttingU shearU stabbing or unctureU imactU crushingU drawing in* which might lead to one or more of the aboveha%ards

Q2 efnethe following terms (some of which you havede7ned in +H1!1):


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U machineryU ha%ardU riskU safeguard

U guardU safety deviceU safe working ractice or safe system of workU interlockU failure to dangerU failure to safety (the referred term is now 9failure to minimaldanger)U integrityA8 >e7nitions

U machinery is aaratus for roducing or alying ower*having 7"ed or moving arts eachwith de7nite functionsU a ha%ard has the otential to cause ersonal in#ury or illhealthU risk is a measure of the likelihood that a ha%ard will result inharm together with the resultingseverityU a safeguard is a guard or device designed to rotect ersons

from dangerU a guard is a hysical barrier that revents or reduces accessto a danger ointU a safety device is a device other than a guard that eliminatesor reduces dangerU a safe working ractice or safe system of work is a method ofworking that eliminates orreduces the risk of in#uryU an interlock is a safety device that interconnects a guard withthe control system or theower system of the machineryU failure to danger is any failure of the machinery* itsassociated safeguards* its control circuits or its ower sulythat leaves the machinery in an unsafe conditionU failure to minimal danger is any failure of the machinery* itsassociated safeguards* controlcircuits or its ower suly that leaves the machine in a safecondition* or rather* a conditionof minimal danger


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U integrity is the ability of the devices* systems and roceduresto erform their functionwithout failure or defeat

Q% Outlinethe hierarchy of control which is aroriate formachine safety&A6 The hierarchy of control which is aroriate for machinesafety: having assessed the riskosed by the machinery in uestion* the solution must then bechosen through the hierarchy of controls (we have added a fewnotes under each heading):U substitution* the use of a safer machine &&&& remember thatthere are legal reuirements for

urchase of new machineryU engineering control to reduce the severity of harm and thelikelihood of harm arising fromthe ha%ard in uestionU administrative control including the establishment ofaroriate working rocedures for day to day oeration andcleaning and maintenance and emergency roceduresU ersonal rotective euiment if all other measures fail toachieve su.cient control

Q#3atching hakeseares seven ages of man* we came uwith the eleven stages in thelife of a machine - what are they* starting with the design of themachineQA1; The eleven stages of machine:U designU constructionU transortU installationU commissioningU oeration* including start-u and shut-downU setting or rocess change-overU cleaningU ad#ustmentU maintenanceU decommissioning and dismantling

QThe selection of guards forms one ste in the hierarchy ofcontrol of machines - what is


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the common aide-memoire used to show the order ofreference for the selection ofguardsQ Xou should be able to rovide e"amles of the varioustyes of guard&

A11 election of guards: 4 + A T& 4i"ed guards being the 7rstchoice* followed by interlock guards* automatic guards and 7na&

Q!(i) 4rom what do the risks in the use of hand tools ariseQ(ii) 4rom what do the additional risks of ortable ower toolsariseQA12(i) The risks in the use of hand tools arise from oerator error*

misuse and imroer maintenance&(ii) The additional risks of ortable ower tools arise from theresence of the ower source (and esecially the electricalcables) and the seed and force of the tool itself&

Q0hy might each ower tool be markedQA1L To identify it for insection uroses as art of a routinemaintenance system&

Q5hat are the general factors about machines and the wayin which eole may come into contact with them which causethe seci7c mechanical ha%ards in any situationQA15 There are si" general factors:W hae of the machineO for e"amle* whether an ob#ect hasshar edges* angular arts* etc&* which may be a ha%ard even ifnot moving&W /elative motion of machine arts or of a machine art to abody* or art of a body&W 3ass and stability of the machine or arts of it* including theworkiece&W Acceleration of moving arts of a machine (or theworkiece)* either under normal conditions or if somethingbreaks&W +nadeuate mechanical strength of a machine or art of it&W otential energy of elastic comonents which may betranslated into movement&

Q1hat are drawing-in in#uriesQ


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A1F These occur where a art of the body is caught betweentwo moving arts and drawn into the machine&

Q6 Identiythe non-mechanical ha%ards arising from the use

of machinery&A1< Coise* vibration* electricity* temerature* ha%ardousmaterials and substances (including radiation) and ergonomics&

Q3hat ha%ards might arise from the use of the followingmachinesQ(i) Mench to grinder(ii) imle robot(iii) neumatic drill

(iv) Mench-mounted sawA1I(i) Mench to grinder: 3echanical O contact* e#ection of arts*swarf Con-mechanical O dust(ii) imle robot: 3echanical - imact!crushing Con-mechanicalO noise(iii) neumatic drill: 3echanical - imact!crushing Con-mechanical O noise* vibration* dust(iv) Mench-mounted saw: 3echanical O cutting!severing Con-

mechanical O noise* dust

Q2hat is the hierarchy of rotective measuresQA18 The hierarchy of rotective measures referred to in the te"tis as follows:W 4i"ed enclosing guardsW Jther guards or rotection devicesW rotection aliancesW The rovision of information* instruction* training andsuervision&

Q%hat 7ve reuirements are there for any guardingsystemQA16 That they should:W Me comatible with the rocessW Me of adeuate strengthW Me roerly maintainedW Cot increase riskW Cot be easily byassed or disabled&


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Q!# escri4ethe rinciles of an interlocking guard system&A2; +nterlocking guards comrise a system which links theoening of the rimary guard to the oeration of a secondsafety device* leading either to the comlete stoage of the

machine or to the oeration of another guard&

Q!hat is a tri deviceQA21 A tri device is a system which stos or reverses themotion of a machine when a erson enters the ha%ard area&

Q!!hat are the limitations of ad#ustable guardsQA22 There are two otentially serious limitations:W They can easily be defeated

W They rely uon oerators being 1;;Y vigilant in roviding fortheir own safety* a condition the guard should rovide* not theoerator&

Q!0hat are rotection aliancesQA2L These are hand held tools or hand controlled 7"ed deviceswhich are used to hold or maniulate a workiece as it entersthe machine* is worked on and!or removed from the machine&

They allow the oerator to kee control of the iece whilst not

coming into contact with the ha%ardous arts of the machine&They include ush sticks* #igs and other tyes of holder&

Q!50ow may two-handed controls be over-riddenQA25 Two eole can over-ride the system by each holding onehandle&

Q!1hen are oerators reuired to be trained in the use ofsafety euimentQA2F At all times and in all situations&

Ele.ent 5 Electrical ha,ards and control

4or many eole* electricity seems to be erceived as a sub#ectof secial obscurity and comle"ity, for this reason* in the'lectrical ha%ards and control element* we decided to adot adierent aroach to usual* namely e"osing students veryearly in their study to tyical C'MJ0 erti7cate e"aminationuestions&


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Q efnethe meaning of the following terms which are+dentifyed in the syllabus: cometence*earthing* isolation* insulation* rotection* reduced voltage*e"cess current rotection*

residual current device and duty holder&A1 >e7nitionsU ometence is de7ned as those working on electricaleuiment must have the necessary knowledge and e"erienceor be under aroriate suervision&3aybe you feel that this is a slightly evasive or circularde7nition but you try to think of abetter way of e"ressing the concet of cometence&U 'arthing &&& very low resistance electrical connection to the

'arth* which* in the event of a faultwill allow e"cess current to $ow away, this $ow to earth shouldtrigger the oeration of a safety device such as a fuse or a rcd&U +nsulation &&& material of such a high electrical resistance thatno electrical current will $owthrough it&U rotection &&& the usual meaning of the word - as we havestressed* rotection which is aroriate to revent irrearabledamage to a iece of euiment (for e"amle* a fuse) may be

insu.cient to revent irrearable damage to a erson (the veryraid circuit breaking action of a rcd is needed to rotecteole)&U /educed voltage &&& most tyes of electrical ower tool can beroduced in versions whichoerate o 11; volts rather than the normal mains 2L; volts&Mecause of the way the electrical circuits for such euimentare constructed (9centre-taed)* in eect the voltage to whicha victim might be e"osed is reduced by a factor of four&0owever* because FF volts is still caable of roducing a fatalshock* other forms of rotection (rcd) will still need to beincororated in the electrical circuit&U '"cess current rotection &&& if e"cess current is $owing in anelectrical circuit* something iswrong* and devices such as the fuse and the rcd are needed torovide the reuired level ofrotection&U /esidual current device &&& very fast acting electrical devicewhich will break the circuit if it


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detects that electrical current is any way being 9silled fromthe circuit - that is actually thesigni7cance of the word 9residual& lease seak to your tutor orhone us in hichester if you wish to discuss further&

U >uty holders &&& we can identify three grous of duty holder*namely: emloyers* self-emloyed eole and emloyees eachwith their seci7c duties which relate to matters which arewithin the control of each of these grous, the /egulationsreuire emloyer ! emloyee co-oeration& when this isnecessary&

Q!hat does 9double insulation meanQA2 >ouble insulation is an aroriate form of rotection in

euiment which no e"osed metal arts may not need to bebonded to earth (earthed) and the electrical circuit willcomrises line (brown) and neutral (blue)& The second level ofinsulation (9double insulation) in such euiment may berovided by lastic casing of the euiment&

Q0hat is the voltage of a circuitQAL Noltage is the measure of dierence in electrical otentialbetween the two terminals of a circuit&

Q5hat determines the current in a circuitQA5 The current in a circuit is determined by the voltage&

Q1hat is the dierence between resistance and imedanceQAF +n rincile* there is no dierence as both terms relate tothe slowing of the $ow of electricity through a circuit&Henerally* resistance relates to the comonents connected to acircuit whereas imedance relates to resistance within theconductor itself&

Q6hat is a short circuitQA< A short circuit is formed where another conductor touchesthe circuit and rovides the electricity with an alternative athto a terminal with a larger otential dierence than the neutralterminal* usually the earth&

Q3hat does arcing doQAI 'arthing rovides a safe ath for any faulty current to bedisersed to earth through a designated conductor&


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Q2hat is the main eect of electric shock on the bodyQA8 An electric shock results in a convulsive resonse by thenervous system to the assage of electricity through that art

of the body* causing the muscles to contract* often violently&

Q%+f a erson receives a shock for one second which assesthrough the body along a ath with an imedance of 1;*;;;ohms* what would be the current received and what eectmight it have on the erson if the voltage of the circuit touchedwas:(i) 25; volts(ii) 11; volts

(iii) F; voltsQA6 Ksing the euation for calculating current from Jhms =awand e"ressing the result in milliams:

(i)+ Z /NZ ;;; 1o*25;Z 25 mA&

This will causestrong musclecontraction andossibly somebreathingdi.culties&

(ii)+ Z /NZ ;;; 1o*11;Z 11 mA&

This will beainful and therewill be somemusclecontraction&

(iii)+ Z /NZ ;;; 1o*F;Z F mA&

This will be barelyercetible*erhas somemild tingling willbe felt&

Q#hat is the 7rst ste in treating a victim of electric shockQ


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A1; The 7rst action should be to break any continuing contactbetween the victim and the current&

Qhat is arcing and what risks does it oseQ

A11 Arcing is the electrical bridging through air of oneconductor with a very high otential to another nearby earthedconductor& +f the arc is connected to a erson* the victim maybe sub#ect to both a $ame burn from the arc and electric shockfrom the current which asses through the body& There is also adanger of burns from ultraviolet radiation and radiated heat*even where the arc does not actually touch a erson& Arcingcan also rovide a source of ignition for 7re&

Q!hy are cable drum e"tension leads dangerousQA12 The bends in the cable increase resistance and may causeoverheating of the conductor&

Q0hat 7ve factors should be used to assess the suitabilityof the construction of an electrical systemQA1L The factors to be considered when evaluating thesuitability of the construction of electrical systems are:W The manufacturers recommendations

W The likely load and fault conditionsW The robable use of the system(s)W The need for suitable electrical rotection devices* such asoverload rotectionW The environmental conditions which may aect themechanical strength and rotection reuired&

Q5hat rotection is oered by the cord gri in a lugQA15 A cord gri restricts movement at the oint of entry of the$e"ible cable into the lug* thus reventing abrasion of thecable& +t also revents the conductors being ulled loose fromtheir terminals&

G1F hat is the dierence between a fuse and a circuitbreakerQA1F A fuse forms a weak link in a circuit by overheating andmelting by design if the current e"ceeds the safe limit& A circuitbreaker is a mechanical device in the form of a switch whichautomatically oens if the circuit is overloaded&


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Q6hat is the urose of a fan in an item of electricaleuimentQA1< A fan is designed to diserse e"cess heat generated by thenormal oeration of the euiment& +t is not designed to

revent overheating from electrical faults&

Q3hat is euiotential bondingQA1I 'uiotential bonding is the rocess of connecting alle"ternal metalwork in the system to a common bondingconductor* thus ensuring that all the metalwork is at the sameotential and* if any of the metal 7ttings become live* currentwill not $ow through the system&

Q2hat is the dierence between switching o and isolationQA18 witching o refers to deriving the euiment of electricower* but still leaving it connected& +solation refers tohysically searating it from any source of electric ower* withthe additional ste being taken of ensuring that it cannot beinadvertently re-energised&

Q%hat rotection is oered by a reduced voltagetransformer in a circuitQ

A16 /educed voltage circuits reduce the eect of any shockreceived from making contact with art of the circuit&

Q!# Statethe main features of a roer system ofmaintenance&A2; The main elements of a roer system of maintenance are:W +denti7cation of the euiment which has to be maintainedand where!how it is to be usedW >iscouragement of Sunauthorised euiment in theworklaceW arrying out simle user checks for signs of damage, fore"amle* casing* lug ins and cable sheathW 4ormal visual insections carried out routinely by acometent ersonW eriodic testing of euiment by a cometent ersonW ystems for the reorting and relacement of defectiveeuimentW /ecording of all maintenance and test results along with theinventory of euiment in use&


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Q!hat checks should be carried out before an item ofelectrical euiment is usedQA21 The erson utilising the electrical euiment shouldvisually check for signs that the euiment is not in sound

condition, for e"amle:W >amage to the cable sheathes* #oints or lugsW The euiment has been sub#ected to conditions for which itis not suitable, for e"amle* it is wet or e"cessivelycontaminatedW >amage to the e"ternal casing of the euiment or there areloose arts or screws&

Q!!hat is the safest method of owering electric hand tools

which are being used outdoorsQA22 +f they cannot be owered by battery* the electrical owershould be delivered through a reduced voltage circuit and!orrotected by a residual current circuit breaker&

Ele.ent 1 ?ire ha,ards and control

Qhat are the essential elements necessary for 7re to occur,e"lain the imlications for 7recontrol&A1 'ssential elements for 7re to occur or continue&0ere you should have described the 7re triangle* emhasisingthat removing any side of the triangle will revent the 7re fromstarting (7re recautions) or will sto a 7re that has started (7re7ghting)&As we have ointed out* almost any uestion on the reventionand 7ghting of 7re can beanswered* at least in art by aroriate mention of the 7retriangle& A rich answer would e"lain that the heat side of thetriangle is actually formed of two comonents - the heat tocreate a vaour (because it is the vaour that actually burns*not the solid or liuid itself) lus the energy to ignite thevaour& ome authorities have argued that it might thus bereferable to talk of a 7re 9suare but it seems as if thetriangle is now too well established to be relaced&

Q! E/plainthe terms: e"othermic and o"idising&


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A2 '"othermic* o"idisingU e"othermic: a reaction that gives out heat as it takes laceU o"idising: the reaction consumes o"ygen (strictly* chemistsmay rovide a dierent de7nition*

but this will su.ce for our uroses)

Q0Mrie$y descri4esome common causes of 7re&AL ommon causes of 7re include:U delayed discovery allowing develoment into a ma#or 7reU combustible material not roerly stored - or disosed ofU resence of e"losive dusts* gases or vaoursU resence of $ammable material (for e"amle* $ammableliuids) in unsuitable containers

U oor building design combined with lack of aroriate 7restoing measures - inadeuate 7re doors* roof voids andcavity walls which allow 7res to develo and sread withoutbeing detected and so onU use of combustible materials in constructionU windows and ! or doors accidentally or intentionally left oenU vandalism resulting in the disabling of 7re 7ghting systemsU arson+magine now that the uestion had asked for the 9rincile

sources of ignition for 7res O although there is obviously anoverla with this 9common causes uestion* your answershould focus on ignition sources such as friction* staticelectricity and so on& (3ake sure that you can indeed +dentifyand describe seven or eight sources of ignition&)

Q5 escri4ethe basic methods of heat transfer in the sreadof 7reA5 Masic methods of heat transfer in the sread of 7re:U conduction (for e"amle: along ies* through brickwork)U convection (via the sace above false ceilings* u stairwells)U radiation (from a burning building or trees across a distanceof many metres)U direct burning (9eating steadily along - remember what wesaid about this)

Q1 Identiythe four methods heat transfer by which thehuman body can loose heat& hich ofthese cannot be involved in heat gainQ


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AF The body may loose heat by the three basic means of heattransfer - conduction* radiation and convection lus heat lossvia sweating (in many situations* the most imortant means ofheat loss)& 0eat cannot be gained by sweating&

Q6 efne:U sontaneous ignition temeratureU lower $ammable limitU uer $ammable limitA< >e7nitionsU sontaneous ignition temerature is the lowest temeratureat which a substance will ignitesontaneously without any e"ternal source of ignition: coal tis*

haystacks and oil soakedrags are some e"amlesU lower $ammable limit is the smallest concentration of$ammable gas or vaour which* when mi"ed with air* iscaable of ignition and subseuent $ame roagationU uer $ammable limit is the highest concentration of$ammable gas or vaour which* whenmi"ed with air* is caable of ignition and subseuent $ameroagation

Q34ire detectors oerate by sensing a change in one or moreof three hysical ! environmentalfactors - what are theyQ Xou should also be able to brie$ydescri4ethe method of oerationof these detectors&AI 4ire detectors are intended to detect an outbreak of7re!smouldering in its early stages bysensing one or more of the following:U heat detectors and $ame detectors have three basicoerating rinciles:V fusion (melting)V e"ansionV infra-red $ame and smoke detectorsU smoke detectors generally fall into three categories:V ionisation detectorsV light scatter detectorsV obscuration detectors(3ake sure that you can brie$y describe all these&)


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Q2 Outlinethe oeration of the two main tyes of automaticsrinkler system&A8 rinkler systems may be divided into two main tyes:U wet systems where the ie work is fully charged with water

at all times and thus there must be no danger of the waterfree%ingU dry installations are installed where the temeratureconditions are arti7cially maintained close to* or below free%ing*for e"amle in cold stores, the ies are ket charged with airunder su.cient ressure to hold back the water suly

Q%4ires and 7re e"tinguishers are classi7ed as lass AO>* 4&Mrie$y outlinethe characteristics

of each lass& hat has haened to lass 'Q hat colour arethe 7re e"tinguishers foreach lassQA6 lasses of 7re and 7re e"tinguishersU lass A 4ires involving solid materials - aer* wood* fabrics&ooling by water or srayfoam is the most eective way of e"tinguishing this tye of 7re&U lass M 4ires involving $ammable liuids such as etrol* oils*fats, foam and dry owder

e"tinguishers should be used&U lass 4ires which are fuelled by $ammable gases such asCorth ea Has* butane and soon& riority must be given to shutting o the source of fuel andthe 7re should be tackledwith dry owder&U lass > 3etal 7res involving metals such as aluminium andmagnesium, secial owdersare reuired in such situations&U (4ormerly known as lass ' 4ires) in which live electricaleuiment is involved& 4or such7res* non-conducting agents such as owder and carbondio"ide must be used, if those7ghting the 7re can* with certainty* disconnect all electricalower* then the 7re can be treatedin terms of its aroriate lass* AO>* 4&U lass 4 0igh temerature ([L


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All e"tinguishers are now to be coloured red although the oldcoding system (cream for foame"tinguishers etc) can be retained as a coloured stri on thee"tinguisher&

Q#hat are the si" main factors to be considered whenassessing a building with regard tomeans of escae in the case of 7reQA1; The main factors to be considered when assessing abuilding with regard to escae in the case of 7re are as follows:U construction of building (layout and materials)U time needed for the comlete evacuation of the buildingU tye of occuancy

U number and location of e"itsU travel distances to the e"itsU management control

Qhat is the urose of emergency lightingQA11 'mergency lighting may be classed as 9maintained (inoeration at all times)* 9non-maintained which is triggeredwhen the normal lighting fails and 9stand-by lighting whichrovides a full relacement system in areas such as an

oerating theatre or a control rocess control centre&'mergency lighting has three functions:U indicate escae routesU rovide su.cient illumination along such routes to ermitsafe escae in case of 7reU ensure that 7re alarms and 7re 7ghting euiment situatedalong the escae route can bereadily located&

Q! escri4ea diagram of a 7re notice&A12 A 7re notice should encomass the following:


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Q0Mrie$y outlinethe factors that may be involved in causinga dust e"losion, what measuresmay be taken to minimise the risk of such e"losionsQA1L 3easures to reduce the risk of dust e"losions include:U good housekeeingU engineering control by use of e"haust ventilation to gather uand disose of e"cess dustU control of electrostatic sources by the use of earthing and soon

Q5 Outline7ve or si" key factors in the revention of liuid7res&A15 The key to the revention of liuid 7res is to control theformation of vaour:U contain the liuid so that vaour does not escae duringstorageU handle the liuid so that sillages are contained and disosedof aroriatelyU rovide ventilation so that any vaour which is created is

disersed


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U control ignition sources - static electricity* electricaleuiment* cigarettes* naked $amesU treat 9emty containers as if they were fullU kee 9immediate use sulies in small uantities in metal

cuboardsU kee bulk stocks in 7re-resisting stores

Q1>itto the revention of 7res involving $ammable gases&A1F revention of 7res involving $ammable gases such aso"ygen and acetylene:U the referred otion is to site gas cylinders outside thebuilding and to ie the gas through7"ed ie work to where it is needed, where this is not ossible*

for e"amle with mobilewelding sets* it will be necessary to take the gas cylinders tothe lace reuired and rotectthem by chaining in racks or trolleysU oerators must be trained in the correct use of $ammablegases: changing cylinders* checkingvalves and connectors* testing for leaks* working roceduresU ensuring good ventilationU storage of full and emty cylinders (referably in secure* well-

ventilated stores in outsidebuildings* never below ground level or ne"t to drains andsimilar)

Q6hat is likely to haen if you oen a window to releasethe dense smoke in a room created by a 7reQA1< The smoke may begin to clear but by allowing fresh air intoan o"ygen-deleted environment the 7re is likely to burn withincreased intensity&

Q3 E/plainbrie$y how each of the following might start a7re&(i) tatic electricity(ii) 4riction(iii) ace heaterA1I(i) tatic electricity is an electrostatic charge roduced byfriction or induction& The charge may be transorted aconsiderable distance from the oint of origin and a sark may


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be roduced when su.cient charge accumulates& This sarkmay have enough energy for ignition&(ii) 4riction is the rocess whereby heat is given o by twomaterials moving against one another& +n the absence of a

lubricant or cooling substance it can result in the surfaces ofthe materials becoming hot or actually roducing sarks* eitherof which may be su.cient to cause ignition& 4riction can becaused by imact (one material striking another)* rubbing(when moving arts of a machine contact stationary surfaces)or smearing (for e"amle*

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