Lecture 5 Hazard Classification in Construction

8/3/2019 Lecture 5 Hazard Classification in Construction

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Hazard Classification

In construction

Hazard Classification

ass azar s: con on or prac ce e y o cause

permanent disability, loss of life or body part and/or

extensive loss of structures, equipments or materials

Class B Hazards: A condition or practice likely to cause

harm, and/or damage of structures, equipments or materials


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Class A Hazards

. ra c an a e y: ra c an s ou e organ ze o

ensure a smooth flow within and/or around construction sites

Recommended Actions:

.

streets or other areas, which restricts access to work areas

.

Class A Hazards

. ra c an a e y:


2. Restrict the speed limit to 25 Km/hr for light vehicles and less

than that for other types of moving equipments inside

construction site.

3. Qualified flagmen should be positioned to alert traffic and

detours. Flagmen shall be identified with orange vests.


3/34

Class A Hazards

. eavy qu pmen : or ers ac on or nac on an or

unanticipated mechanical failure of machinery may causeaccidents.

1. Post back-up spotter for all heavy equipment.

2. Clear work area of personnel before operating heavy

.

3. Provide designated parking area in and around construction

site.

Class A Hazards

. eavy qu pmen :


4. Booms, forklifts, pay loaders and the like should be kept at a

safe distance from overhead-energized lines. It should be

kept at least 6 meters with power lines up to 250,000 volts

and 7.5 meters above 250,000 volts.

. ,

except riggers doing some rigging work.


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Class A Hazards

. eavy qu pmen :


6. Operator should receive signals only from authorized and

qua e emp oyees ass gne or e purpose.

7. Detailed and regular ins ection of all hoists es ecially load

hooks, ropes, brakes, tires, hydraulic leaks, limit switches

...etc. should be schedule.

8. All booms should be lowered after each shift, except

o erw se au or ze y s superv sor an e sa e y

representative

Class A Hazards

. eavy qu pmen :


9. Provide escort when moving cranes around construction

site.

. ,

equipment is properly parked e.g. parking brakes applied.

11. Heavy equipment operator sunshades obstructing clearviews are prohibited. All vehicles must have 360o clear

view.


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Class A Hazards

. eavy qu pmen :


12. Only authorized personnel shall operate heavy equipment.

13. Level crane in all direction before lifting.

14. Survey site for utility Hazards such as buried cables and

pipe lines and develop operating procedures for working intheir vicinity.

Class A Hazards

. eavy qu pmen :


15. During travel, crane hooks must be anchored to the crane

body to avoid swinging freely.

-.

/ equipments.

17. Operator should not allow unauthorized personnel tooperate the equipment assigned to him, nor should he allow

such persons to ride on the equipment while it is moving.


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Class A Hazards

. eavy qu pmen :


18. Operator should determine safe clearances of overhead

obstructions and building openings, and to proceed only

when satisfied.

Class A Hazards

. ng qu pmen : eavy equ pmen an mec an ca

hoisting machines are commonly used for lifting loads.

Likewise actions are also indicated for Cables and Slings,Wire Ropes, Hooks and pulleys.


1. Inspection of equipment must be done by a qualified

ins ector ever three months or after ma or re airs. Cranes

shall have test certificate and sticker.


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Class A Hazards

. ng qu pmen :


2. Barricade the area during lifting operation and re-direct

traffic/personnel.

. .

4. Only qualified rigger or authorized personnel shall be allowedto attach slings to loads being lifted and give signal to crane

operator.

Class A Hazards

. ng qu pmen :


5. No loads shall be attached to the hook while cranes are

traveling.

. .

7. Operator shall not leave his position at controls while load is

suspended.


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Class A Hazards

. ng qu pmen :


8. Timber pad support of substantial size beneath outrigger

floats shall be provided for all crane working at

unpaved/loose ground.

9. Lifting operations shall be stopped if wind speed is over 35

. .

10. Open mouthed hooks, e.g. C, S or half link hooks are not

allowed.

Class A Hazards

. ng qu pmen :


11. Riding on loads, hooks, material hoists, or buckets, is

prohibited, except for especially devised equipment for

elevated work and all personnel are equipped with safety

belts properly secured.

.

hook approaches personnel, a warning horn signal shall be

sounded to warn personnel within the vicinity.


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Class A Hazards

. ng qu pmen :


13. Side pulls shall not be made directly over the load to be

lifted.

. ,

proper locks and braking equipment, which shall be capable

the full rates load.

Class A Hazards

. ec r ca : s r u on o e ec r ca power on cons ruc on s e

is different from permanent installations.

Recommended Actions:Portable Electrical Equipment and

1. Only qualified electricians shall use or repair electrical

equipment.

. ,

installations shall be equipped with approved type Ground

Fault Circuit Interrupter (GFCI)


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Class A Hazards

. ec r ca :

Recommended Actions:Portable Electrical E ui ment and

Flexible Cords

3. Extension cords and cables must be connected to junction

boxes of molded rubber.

4. All receptacle outlets voltage should be 240 volt single

, .

5. Inspect electrical equipment and tools before using and

remove from site any damage ones.

Class A Hazards

. ec r ca :

Recommended Actions:Portable Electrical E ui ment and

Flexible Cords

6. Visual inspection of portable cord and plug connected to

equipment and flexible cord sets must be done regularly.

7. Over loading of electric circuits is prohibited all circuits shall

.


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Class A Hazards

. ec r ca :

Recommended Actions:Workin on Live E ui ment

1. Only qualified trained electricians will be allowed to work on

live electrical equipment.

- -. .

3. Do not allow any employee to work alone on any liveelectrical equipment.

.

until proven that they are not.

Class A Hazards

. ec r ca :

Recommended Actions:Workin on Live E ui ment

5. Non-conductive or insulated tools shall be used on or near

energized equipment.

-.

working on live equipment.

7. Work must be properly planned before executing.


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Class A Hazards

. ca o ng an or a orms: n some p ases o wor ,

erecting scaffolding of different types or construction workplatforms will be needed. Necessary steps should be taken in

performing these jobs.


1. Scaffolding and platforms shall be erected only by qualified

scaffolders.

2. Warning signs and barriers shall be provided to keep un-

necessary personnel away from the base of scaffolds.

Class A Hazards

. ca o ng an or a orms:


3. Use of personal protective equipment on and below scaffolds

and work platforms shall be enforced such as safety belt and

helmets.

4. If possible, tie scaffolds to solid structures every 7.9 meters

. .

5. All scaffold components shall be in good condition and

inspected regularly for damage or wear.


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Class A Hazards



6. Scaffolds shall have guard rails (top and midrail), toe boards,

ladder, bracing and other supports, which are of appropriate

strength to carry the imposed loads. Top rail at least 106 cm,

midrail are approximate 55 cm and two boards at 10 cm

hei ht. Timber sills wood lanks shall be at least 23 cmwide by 3.8 cm thick. A guard rail should stop a 100kg side

.

Class A Hazards



7. Mobile scaffolds shall not be moved with men equipment, or

materials riding on the scaffold.

.

cannibalized for use with different scaffold system.

9. Outrigger bracing against the ground shall be used onerected scaffolds more than two sections high.


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Class A Hazards

. e ng an u ng: e ng an cu ng w e requ re

during various phases of construction; Hazards will arise frommolten slag, ultraviolet rays, open flames, hot electrodes and

electric shocks.

Recommended Actions:ARC Welding & Cutting

1. Ground the welding equipment by bonding to the ground of

the main su l s stem with se arate substantial conductor.

2. Close all doors, covers and panels when operating the

equipment.

Class A Hazards

. e ng an u ng:

Recommended Actions:ARC Weldin & Cuttin

3. Electrode holder and connector shall be free from cracks or

damage and all connections made tight.

.

power tools plugged into welding equipment auxiliary outlet.

5. In remote areas, electrically bond the equipment to a metalwater pipe.


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Class A Hazards

. e ng an u ng:


6. Fire extinguisher must be provided for every welding and

cu ng o .

7. Pro er electrical contact shall exist at all joints when a

building structure or pipeline is used temporarily as ground

return circuit.

8. Pipelines containing gases or flammable liquids or conduits

carry ng e ec r ca con uc ors w no e use or a groun

circuit return.

Class A Hazards

. e ng an u ng:


9. Cables shall be substantially supported overhead. Special

care shall be taken to see that welding supply cables are not

near to power supply lines or other high tension cables.

10.Welding cables shall be kept dry where practicable and free

.


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Class A Hazards

. e ng an u ng:

Recommended Actions:Gas Weldin & Cuttin

1. Cylinders shall be stored in a well-ventilated location and

shielded from direct sunlight with steel plate or non-

combustible canvass.

2. Before starting work, a leakage test shall be made at all

.

3. It is preferred to have the cylinders in use secured in portable

racks or handcarts.

Class A Hazards

. e ng an u ng:


4. Acetylene regulator pressure shall not exceed 15 psi (it may

explode above 15 psi).

. ,

loaded on cradles, net or skid pans, but never in slings or

.

6. Isolate oxygen cylinders from acetylene cylinders at least 6.6

meter or with fireproof barrier/wall at least 1.6 meters high.


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Class A Hazards

. e ng an u ng:


7. All compressed gas cylinders should be used in a chained

vertical position and when not in use should be capped,

chained and stored in vertical position.

8. Torches shall be constructed of brass, bronze or stainless

.

9. Cylinders shall be tagged Full and Empty cylinders shall be

returned immediately to the storage area.

Class A Hazards

. e ng an u ng:


10.Shielding or welding curtain (fire blankets) shall be placed

around work area to protect other personnel from flash and

sparks.

11.Do not use copper or silver in any system containing

.

12.Fire extinguisher must be provided for every welding and

cutting job.


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Class A Hazards

. e ng an u ng:


13.When work is completed, the cylinders valve shall be

c ose , an regu a ors an oses s a e remove an pu

in proper place.

14.Grease and oil must never be used near oxygen.

. ose connec ons s a e ma e roug su s an a ngs,

and clamped or otherwise securely fastened so as to

w s an , w ou ea age a pressure w ce as grea as e

maximum pressure on the system.

Class A Hazards

. xcava ons: xcava on or oun a ons an u y renc es

represent a hazard for personnel and equipment on site.

Workers and equipments may accidentally fall into excavationand/or toxic gases may accumulate or danger of excavation

collapse.

ecommen e c ons:

1. Provide a roved shorin on all excavations over 1.20m

deep. Excavation over this deep must also comply with, .


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Class A Hazards

. xcava ons:


2. Place signs Danger Keep Away and use warning tape as

a barricade. For deep excavations, physical barricade will be

required.

3. Provide ladder for access and egress in trenches not

.

1m above step-off point.

Class A Hazards

. xcava ons:


4. Spoil bank (soil) and any equipment to be kept at least 1.2m

back from edge of deep excavations.

. ,

required for pedestrian traffic or to access any equipments.


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Class A Hazards

. on ne pace n ry: s s e ne as any wor area

with limited or restricted access or workers are out of sight ofobservers, or where emergency egress is difficult or where

hazardous gases can collect or accumulate.


1. Conduct gas tests before entry.

.

sufficient natural draft of air or by installing air movers.

Class A Hazards

. on ne pace n ry:


3. Ensure mobile equipment such as generators is placed so

that exhaust gases do not contaminate the confined space.

.

and egress

5. An entry attendant is required each time a person enters theconfined area.


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Class A Hazards

. on ne pace n ry:


6. Ensure adequate lighting. All electrical lighting shall be

explosion proof in areas where flammable vapors are likely

to be present. Lighting systems shall be rated at 25 volts or

less.

.

be connected to an air compressor approved for breathing air

service.

Class A Hazards

. on ne pace n ry:


8. Provide a ground fault circuit interrupter (GFCI) for 100 volt

electrical equipment inside the confined space.

.

hearing protection, respirators and chemical protective

.

10.Welding gas cylinders or any other compressed cylinders are

not allowed inside the confined space.


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Class A Hazards

. on ne pace n ry:


11.Prior to the use of gas welding equipment, inspection should

be done to ensure that all equipment is free of leakage.

Class B Hazards


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Class B Hazards

. ower oo s: azar s w ar se w en uns e an

untrained labors are allowed to operate power tools.


1. Only qualified and trained personnel are allowed to use

power tools.

2. Foreman of the trade shall make sure that his labor is familiar

.

3. Inspection and maintenance of all power tools shall be done

at least once a week by a competent technician.

Class B Hazards

. ower oo s:


4. All power tools shall be ground and of double insulated type

cable.

. .

6. Proper shields or guards shall be attached for power tools

such as grinders, cartridge operated tools.


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Class B Hazards

. a n ng an es ves: a n s an a es ves are source

of Health Hazards because of their chemical nature.


1. Use proper mouth, hand/skin, nose and eye protection

equipment during application.

2. Ensure that enough ventilation is properly maintained at all

.

3. Maintaining food housekeeping.

Class B Hazards

. oncre e ac ng an n s ng: emen s a s n an eye

irritant and because of its messy nature, it can be a source of

hazard during handling and application .

1. Use of hand, ear and eye protection equipment is required.

2. Use of rubber boots to protect feet is necessary.

3. Use of warning signs at fresh placed concrete.

4. Removal of s illed concrete.

5. Proper handling of concrete must be observed.


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Class B Hazards

. ressure es ng: y ro an neuma c ressure es ng s

a source of many hazards because the risk of possible failureis appreciably greater during testing.

1. Erect barrier tapes and placed warning signs, etc.

2. Use of pressure relief valves during testing.

3. Ensure that pipe ends, connections and all fittings are in

good condition to avoid ruptures.

Class B Hazards

. ressure es ng:


4. Inspect and check visually for defects the testing equipment

and associate accessories, such as hoses, fittings, and

ensure the condition before testing and shall meet test

pressure requirements.


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Class B Hazards

. ompresse r qu pmen : ere are some equ pmen

that are driven by compressed air such as jack hammerswhich are normally used on site to break and demolish

existing pavement, i.e. , concrete or asphalt or associated

accessories may result to minor or major injury.

ecommen e c ons:

1. Ensure that o erator and ersonnel in the vicinit of noisequipment in use wear earplugs and other personal

.

Class B Hazards

. ompresse r qu pmen :


2. Ensure no over pressure is taking place. Regularly check

pressure relief valves.

.

type clamps and strong wire.

4. Damage hose must not be used. Visual inspection and checkof the equipment and accessories, especially the air supply

hose shall be done regularly.


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Class B Hazards

. ompresse r qu pmen :


5. Ensure that air supply machine is monitored by another

person to continuously observe the pressure of the supplied

air.

Class B Hazards

. ras ve an as ng: ras ve an as ng o s ee

components before painting represents risk for both the

worker doing the cleaning as well as other workers within thevicinity of the operation.


1. Both operator and helper must wear full protective clothing

desi ned for abrasive blastin o eration, a roved air su l

including full face shield with respirator, helmet, industrial, .


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Class B Hazards

. ras ve an as ng:


2. A Dead Man switch/valve shall be fitted in the nozzle control

for automatic shut-off in case the operator accidentally

releases the nozzle.

3. Grit shall be frequently removed to avoid accumulations and

.

4. Frequent watering of the work area shall be done to minimize

dust accumulation.

Class B Hazards

. ras ve an as ng:


5. Other workers in the vicinity shall be kept away upwind as far

as possible from the sand blasting area or operation by

barriers and warning signs.


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Class B Hazards

.

activities POSES a great hazard to our hearing and should.


1. The Project Management and the Safety Representative will

conduct re ular review of the work area and determine where

workers need hearing protection. As a guide, if you have to

raise you voice to be heard over the noise, then hearingprotection is needed.

.

excessive noise.

Other Potential Risks


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.

construction work. The manner materials are handled can.


1. Assign qualified person to control materials handling

o eration. Re-route the edestrian and vehicle traffic if

required during the material handling by providing barricades

and warning signs.

2. Flammable and/or corrosive materials must be stored in

be posted stating the nature of the hazards.


.


3. Adequate fire fighting equipment must be provided in all

.

4. When storing materials, make sure that the floor will support

e we g , an a ac es ave een prov e or easy

access of material.


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.


1. Learn the mode of operation of fire extinguishers, and proper

.

extreme importance during emergency.

. s a so u e y pro e o smo e or use open ames n

restricted areas, which have been provided with No

.

3. Do not handle or store flammable liquids in bottles, open

cans, etc. approved safety containers with cover and

markings must be used.


.


4. Oily waste rags, etc. should be disposed of in metal cans with

.

5. All rubbish shall be cleared from work areas to avoid

accumu a on o com us e ma er a s.

6. Temporary high voltage wires shall not be run above storage

piles or combustible materials.


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.


1. Never leave unprotected floor opening. If the job has not

,

it; in addition, warning lights should be installed.

. oose o ec s a may nvo ve s um ng azar s s ou

be removed from the floor immediately, especially on, or in

,

stairways, ramps, etc.


.


3. Round goods or materials like drums, barrels should be

.

4. Broken glass is dangerous and should not be pick up with

a e an s, sweep up.

5. Never leave protruding nails where they can be stepped on

by other persons. If nails cannot be pulled out or bentimmediately, protruding nails should be pilled out of the way

nails facing down, until they can be transported to a more

suitable location to do so.


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.


1. Never substitute proper tools, materials or equipment, useonl a roved and ri ht tools for a s ecific ob.

2. It is dangerous to carry up-ended sharp or pointed tools in. .

3. Provide ground fault circuit interrupter (GFCI) for all power.

4. Brittle tools such as files and rasps, must not be stuck witho er me a oo s. es an o er oo s w po n e s emsmust not be used without corresponding handles.


.


1. Only experienced and authorized workmen should operate

proper care.

. erson n c arge o e un s ou con uc regu ar

inspection of woodworking machines; tools and other related

.

3. Smoking is strictly prohibited inside the work/ machine shop.


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.


4. Woodworking machines should have a master switch that

.

5. Power saws should not be stopped too quickly, nor is a piece

o woo rus e aga ns e cu ng e ges w en power s

shutoff.

6. When operating a power saw, do not stand in line with it.

Stand on one side to avoid being hit by a possible kickback.

Lecture 5 Hazard Classification in Construction

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