Day Eight Questions NEBOSH

8/20/2019 Day Eight Questions NEBOSH

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Day Eight Questions (NIGC)

1. Outline the hazards to which a worker could e e!"osed when cutting

down a tree using "etrol dri#en chainsaw. ($)

Chainsaw (%etrol Dri#en)& 'azards

• Cutting on contact with o#ing lade.

• Entangleent with o#ing lade.

• Drawing in at ni""oint etween lade and casing.

• %uncture y e*ected "arts (es"ecially roken lade +ragents).

• ,urns on the hot e!haust syste.

•

Noise.• -iration (into hands).

• ire and e!"losion +ro "etrol (+uel).

• Ergonoic +ro handling.

• 'ealth hazards +ro dust/ +ues and luricating oils.

0. Outline +our ain ty"es o+ guards and sa+eguarding de#ices that ay e

used to reduce the risk o+ contact with dangerous "arts o+ achinery. ($)

Fixed Guards

• Co"letely "re#ent access to dangerous "arts o+ achinery

• re +i!ed in "lace

• 2e3uire a tool +or reo#al

Interlocked Guards

Guard o"en&

• %ower to the achine is disaled when the guard is o"en and it will not

o"erate until the guard is in "lace

Guard closed&

• 4he guard is locked shut until the achine has returned to a sa+e

condition

• 4he act o+ o"ening the guard sto"s the dangerous "arts o+ the

achinery and disales "ower


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Adjustable/Self-Adjusting Guards

5sed when it is not "ossile to "re#ent access to dangerous "arts

• d*ustale guard

o 6et anually to a range o+ "ositions y the o"erator • 6el+ad*usting guard

o 5sually s"ringloaded to ad*ust itsel+ to the work"iece

o 2e3uires no ad*ustent y the o"erator

Trip Devices

• Not a "hysical arrier • 5se sensors to detect "resence o+ o"erator and sto" the achine

• 4hey include&

o "ressure ats

o tri" ars

o "hotoelectric de#ices

• 7iitations88

Liitations include

o#erriding y e.g. "lacing a "lat+or o#er the "ressure at/

9ay not o"erated +ast enough

4ri"s ay lead to "roduction delays

:. Gi#e the answer o+ elow 3uestions ;

a) Identi+y +our echanical hazards associated with the use o+ a "edestal

drill. (


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• Drawing in at ni""oints etween otor and dri#e elts.

• Electricity.

• Noise.

• 'ot "arts (es"ecially the drill it).

•'ealth hazard +ro cutting +luid (e.g. deratitis).

) Outline +our control easures to reduce the risk o+ in*ury to o"erators o+

"edestal drills. (


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) Outline control easures that could e taken to reduce risk. (


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• Noise.

• -iration.

• ire and e!"losion +ro "etrol (+uel).

• 'ealth hazard +ro sensitisation to grass sa"/ "ollen/ etc.

%rotection

• i!ed guards o#er dri#e echanis.

• 6a+ety switch under seat to ensure that dri#er is in seat e+ore achine

will o"erate.

• 5se restricted to trained o"erators only.

• 'earing "rotection.

• 2e+ueling carried out in well#entilated area.

• Ao rotation ay e necessary to liit #iration e!"osure.

• 5se restricted +or workers with sensitization.

$. Outline +ollowing;

a) De+ecti#e conditions o+ non"owered hand tools that could "resent risks

to the user. (0)

) 4he re3uireents +or the sa+e use o+ non"owered hand tools. (0)

4ools ust e suitale +or the task that they are going to "er+or and +or the

en#ironent in which they are to e used/ e.g. nons"arking tools (do not

"roduce s"arks when struck) are suitale +or use in a "otentially +laale

atos"here.

B. Outline the +unction and ad#antages o+ +ollowing;

a) i! Guard. (0)

+i!ed guard is a "hysical arrier that "re#ents a "erson +ro coing into

contact with dangerous o#ing "arts. 4he guard ay y sha"ed to +it the

achine 3uite closely (enclosing guard)/ or it ay e ore like a +ence

around the achine ("erieter guard). It ay ha#e o"enings in it (e.g. to

allow raw aterial to e +ed into a achine)/ ut these ust e designed in


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such a way that it is not "ossile to reach in and contact dangerous "arts

(distance guard).

) utoatic Guard. (0)

c) Interlock Guard. (0)

n interlocked guard is a "rotecti#e de#ice designed to e reo#ed as a

noral "art o+ routine achine o"eration. 4he guard is intended to allow

+re3uent access to a achine or danger zone y reo#ing the "ower source

and "re#enting the e3ui"ent +ro o"erating while the guard is o"en. ?henthe guard is reo#ed a sa+ety interlock syste "re#ents achine o"eration.

d) d*ustale Guard. (0)

d*ustale and sel+ad*usting guards are used when it is not "ossile to

co"letely "re#ent access to dangerous "arts. 4hey are coonly used to

sa+eguard woodworking and etalworking achinery where a work"iece

has to e +ed into the achine or ani"ulated during achine use.

1. Identi+y +our echanical +our non echanical hazards "resented y

hand held electric grinder and outline in each case how in*ury ay occur. ($)

6ecure grinder in "osition.

• i!ed enclosing guards around otor and "art o+ arasi#e wheel.

•

d*ustale "olycaronate eye guards o#er e!"osed "art o+ wheel.• 4ool rest ad*usted to iniise ni" "oint etween rest and wheel.

• 5se and setting restricted to trained o"erators only.

Eye "rotection (i"act resistant).

• 'earing "rotection ay e necessary.

• Installation o+ 7E- ay e re3uired to control dust.

•

2outine aintenance/ including ins"ection and "ortale a""liancetesting +or electrical sa+ety.

• 2egular checks o+ the grinding wheel.


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• 2egular checks to ensure correct grinding aterial has een selected.

• O"erators to a#oid loose clothing which ay ecoe entangled.

• I+ used +or "rolonged "eriods/ *o rotation ay e a""ro"riate to

reduce e!"osure to noise and #iration.

•5se restricted to trained o"erators only.

11. ?ith re+erence to an accident in#ol#ing an o"erator o+ lathe achine

who coes into contact with a dangerous "art o+ the achine outline

+ollowing;

a) 4he "ossile iediate causes. (0)

) 4he "ossile underlying causes. (0)

10. Outline the hazards associated with the use o+ a circular saw and outline

general control easures against each hazard. ($)

'azards

• Cutting on contact with lade.

• Entangleent with dri#e otor.

• Drawing in at ni""oints etween otor and dri#e elt.

• E*ection o+ work"iece during cutting.

• Electricity.

• Noise.

• 'ealth hazard +ro inhalation o+ wood dust.

%rotection

• i!ed guard +itted to otor and otto o+ cutting lade.

• d*ustale to" guard +itted ao#e lade.

• 2i#ing kni+e +itted ehind lade ("re#ents the tier +ro "inching

shut on the saw lade a+ter it has een cut which can lead to the

tier eing kicked ack towards the o"erator).

• 'earing "rotection.

• Eye "rotection (i"act resistant).• E!traction #entilation or res"irator ay e necessary.


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• 2outine ins"ection and "ortale a""liance testing.

• 5se restricted to trained o"erators only.

1:. Identi+y "reuse checks +or electrical sa+ety that should e carried out on

+ollowing;

a) %ortale drill. (0)

) 'and 'eld Grinder. (0)

1)

1@. Gi#e the eaning o+ the +ollowing;

a) -oltage. (0)


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easure o+ the "otential di++erence or electrical dri#ing

+orce"ressure that is +orcing electricity through the conductor (unit& #olt;

syol& -).

) Current. (0)

easure o+ the rate o+ +low o+ electricity through a conductor (unit&

a"ere or a"; syol& I).

c) 2esistance. (0)

easure o+ how uch a co"onent in the circuit resists the "assage

o+ electricity (unit& oh; syol& 2).

1$. Identi+y "ossile e++ects on the huan ody +ro a se#ere electric shock.

(


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o+ in*ury reduced.

c) Doule Insulation. (0)

4he "rinci"le ehind doule insulation is e!actly as suggested&4here are two layers o+ insulation etween the user and any li#e conductors.

4his eliinates the need to "ro#ide earth "rotection/ so douleinsulated

e3ui"ent will ha#e a twocore +le!& li#e (hot) and neutral only. Doule

insulation is coonly used as the eans o+ "rotection +or handheld

"ortale electrical e3ui"ent such as hedge triers.

d) Earthing or grounding. (0)

Earthing is a way o+ "rotecting e3ui"ent so that in the e#ent o+ an electrical

+ault/ current +lows sa+ely to earth rather than +lowing through a "erson who

ight e touching the e3ui"ent. 4he earth wire o+ an ite o+ electrical

e3ui"ent is usually connected to the outer etal casing or chassis o+ the

e3ui"ent. I+ a +ault de#elo"s and the casing or chassis ecoes li#e then a

current will +low down this earth wire. Electricity alwaystakes the "ath o+ least resistance/ and since the earth wire will ha#e #ery low

resistance the a*ority o+ +ault current will +low sa+ely to earth through the

wire. ny "erson touching the casing will recei#e a inor shock.

01. 7ist the +actors when deterining the +re3uency o+ the ins"ection and

testing o+ electrical e3ui"ent at construction sites. (


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,) ?orking on high #oltage electrical "anels. (0)

C) ?orking in the #icinity o+ li#e o#erhead "ower lines. (0)

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Day Eight Questions NEBOSH