Workplace Hazards and Risk Control Essay
Workplace Hazards and Risk Control
· Unexpected collapse of the trench wall /cave in: Sudden collapse of the excavation walls normally happens due to the condition of soil, presence of water, vibrations due to activities in the vicinity, lack of support etc. Severe crush injuries can result from even relatively small collapse as soil is very heavy
· Falling of persons / workers into the trench: Falling of persons normally happens as a result of unfenced edges or while climbing in to or out of the excavation from ladders
· Presence of toxic gases during the trenching: Excavations can get filled with any gas that is heavier than air or other gases in the surroundings can get leach out of the soil and into excavation
· Accumulation of water: Flooding usually happens from surface water due to heavy rain, ground water or due to the rupture of water pipelines.
· Oxygen Deficiency: Deficiency of oxygen may happen due to the depth of excavation / Trench
· Fire due to the presence of underground utilities carrying flammable materials
· Collapse of the adjacent structure: Excavation works can affect the foundations of nearby buildings causing destabilizing or collapse of the structure
· Biological Hazards
· No proper access/ egress
· Mobile equipments falling into the pit
· Inadequate illumination
To avoid the unexpected collapse of the trench / excavation wall, the wall should be protected by means of sloping, shoring, benching or shielding. Check for the presence of underground utilities before the start of the work. The plans of the area of the excavation should be obtained. The buried services should be located using surface clues and detection equipment. The buried services should be discovered by careful digging with hand. Before performing the mechanical excavation, underground utilities should be isolated if possible. The perimeter of the excavation should be protected by means of hard barricades, so as to avoid the unauthorized entry of personnel into the work area and to avoid the vehicles running close to the excavation.
The pit / excavation should be periodically monitored by means of detectors to detect the presence of toxic gases as well the availability of oxygen. If the presence of toxic gases is identified it should be removed by providing adequate ventilation or supply the workers with adequate respiratory protections. Accumulated water inside the excavation / trench should be removed by providing adequate dewatering systems (pumps & motors) and protected against the runaway water (Spoils). Adjacent structures near to the excavation should be protected by providing adequate physical support or underpinning to the structure. Proper lighting and caution boards should be provided in and around the excavation area.
Ladders should be provided for the movement of workers into and out of the excavation correspondingly ramps should be provided for the movement of vehicles. The excavation should be made subject to a permit to enter. Forced ventilation, air monitoring and respiratory protective equipment may be necessary. Excavation should always be inspected by a competent person before the start of work, accidental fall of materials and after any undesired or unexpected events. Vehicles should be prevented from approaching the excavation side by use of barriers and signage’s. Employees working in excavation should be provided with adequate personal protective equipment’s. Periodical inspection should be performed before, during and after excavation.
Mobile Scaffold (Mobile Tower Scaffold):
· Falling of personnel from the working platform
· Objects falling from the platform or due to the work activity
· Collapse of the structure due to overloading, inadequate construction, inadequate bracings, lack of maintenance etc.
· Overturning of the structure (moving the structure through uneven surfaces, overloading at edges, broken castor wheels, moving with personnel on top etc.)
· Contact with overhead electrical line
· Collision with the obstructions or vehicles
Following factors need to be considered when using a mobile tower scaffold: Guard rails must be fitted on the work platform
Tower must not be over loaded
Wheels should be locked when the tower is in use
Tower must be sited on firm and level ground
People and materials should not remain on the tower when it is moved Care should be taken to avoid the overheads when the tower is moved Outriggers should be used where necessary to ensure stability Mobile tower should be built by trained workers
Tower platforms should be fully decked
Castor wheels should have adequate strength
The mobile scaffold in use shall rest upon a suitable footing and shall stand plumb All wheels shall be provided with a positive locking device to hold the scaffold in position Demolition:
Some of the hazards that may be presented during the demolition of the building may include the following:
Unintentional collapse of the building being demolished or the adjoining structures because of the lack of temporary support, buildup of debris, weakening of load bearing sections etc. Debris falling from height during the demolition
Fires, explosion, electrocution etc. due to services not being isolated Health hazards from chemicals, asbestos, lead based coatings, biological contaminations etc. Personnel falling due to unsafe place of work or due to improper access / egress Hazards related to the use of explosives
Hazards related to the manual handling of heavy loads
Site Security for Children:
Some of the security measures that should be considered to prevent the entry of the children into the construction sites are:
Fencing / Barricading the site
Fencing / Covering excavations/ trenches
Display of warning signs and caution boards
Visiting the neighborhood and informing the parents about the work activities Visiting the schools and conducting awareness programs
Monitoring by the use of security patrols and closed circuit televisions Posting caution boards near excavated pits and dangerous machinery Removing ladders and denying access to the scaffoldings
Mobile Elevated Working Platform (MEWP)
The safe working practices that need to be followed while using a mobile elevated working platform include:
Operated by a trained, experienced and competent operator
Operated on a firm and level ground
Do not overload it
Cordon the area when in use.
Outriggers fully extended.
Ensure no overhead obstruction
Do not operate under overhead electric lines
Move the equipment keeping the platform low.
Before use check whether the brakes, limit switches are in working condition. Safe working load be displayed
It should be inspected as an item of lifting equipment designed to carry people. Violence
Works that has the proximity for violence at work:
Handling money or valuables – cashiers,
Providing care, advice, education and training (nurses, ambulance staff, social workers, teachers)
Carrying out inspection or enforcement duties (police and traffic wardens, ticket inspectors) Working with mentally disturbed, drunk or potentially violent people (prison, officers, bar staff, mental health workers)
Working alone (home visitors, taxi drivers, and domestic repair workers) Control Strategies:
Zero tolerance policy and prosecution to offenders, Queue management and information, Change the job to give less face to face contact, Use cheques, credit cards, tokens instead of cash, Check credentials of “clients” and meeting locations, Avoid lone working in high risk areas, Call-in system for lone workers, Arrangements to get staff home if working late, Training employees to deal with aggression, Changing public waiting areas, Video cameras, alarm buttons, visible security staff, Protective screens and coded security locks, keeping record of past incidents and vetting customers, security doors between public areas and staff areas, Panic alarms, Visitors should not be allowed after dark, secure parking areas for the staff.
Movement of People – Slips & Trips
Factors that may cause slips & Trips:
Floor Surface: Slippery floor, holes on the floor, uneven floor, smooth floor Contamination: Spillages, Leaks
Obstructions: Rubbish, trailing cables, rugs etc.
The Task: How the task is performed: Carrying loads that is not properly arranged, Overloading, obstruction of vision etc.
Environment: Inadequate lighting, dusty atmosphere etc.
Footwear: Unsuitable footwear
The People: Unaware of the dangers
Risk Assessment: Conduct a risk assessment on the path, which is used by the employees for movement to identify the hazards and to provide the control measures. Floor Surface: Provide Non Slipper y floor and even floor ; ensure no pot holes on the floor; Contamination: Ensure no Spillages and Leaks of water, grease , oil on the floor Obstructions: Keep the Rubbish & its bins at the side of the path, route the trailing cables so that it does not obstruct the path, ensure no loose rugs placed which would cause trip etc. The Task: Ensure employees carry loads not more than their capacity. Loads carried do not block their view. Give them enough rest pauses if the load is carried for long distance. Provide enough space to work.
Environment: Provide enough Lighting at the passages, adequate ventilation if possible to remove the dust or smoke persisting in the workplace
Footwear: Provide suitable footwear or inform them to wear appropriate foot wears. The People: Make employees aware of the hazard on the path they move. Designated walkway: Provide designated walkway for people movement. Reporting: Inform employees to report hazards they noticed to the management Independent Tied Scaffold:
Scaffolds should always be erected under a competent supervisor Only experienced and trained employees be deployed for the work No damage scaffold material to be used
Factor of safety for all components on a scaffold is 4
Ground shall be even, firm, and capable of carrying the scaffold weight Unstable objects such as barrels, boxes, loose brick or concrete blocks shall not be used to support scaffold base
Base plate shall be used to spread the load of the scaffold All scaffold posts (standards) shall be pitched on steel base plates Screw jacks shall be used to compensate for variations in ground level Scaffold posts and frames shall be erected and maintained vertical and plumb and vertically braced in both directions to prevent swaying and displacement Adequate Ties or guys shall be provided to meet the design requirements of the scaffold. Every scaffold platform shall be closed planked or decked as fully as possible between the guardrails
Platforms shall be kept free of obstructions, unnecessary materials, projecting nails and other unnecessary tripping hazards (including uneven decking)
Adequate space for workers to safely pass shall be provided and maintained wherever materials are placed on platforms or if any higher platform is erected thereon Platform units that have become slippery with oil, sand, or any other substance shall be cleaned, or otherwise removed and replaced, prior to continuing use
Effects of Heat on Workers:
Working on the hot and humid climatic conditions usually has large impacts on the health of the workers. Some of the effects of the temperature on the
human body are listed below: Sun Burns – Too much of exposure to sun or working in humid conditions can cause reddening of the skin along with painful / blistering peeling of the skin Heat Exhaustion – Working in hot or humid climatic conditions may cause fluid loss in the form of sweating which also causes loss of salt from the body. Inadequate water intake under these circumstances causes body cooling system to break down
Heat Rashes – Exposure to humid conditions can cause red bumpy rash with severe itching on the skin
Fainting – Fluid loss and inadequate intake of water can cause dehydration which can result in fainting.
Heat Stroke – When the human body has used up all its water and salt reserves it will stop sweating which can result in stroke.
Remove or reduce the source of heat where ever possible, control the temperature using engineering controls e.g. change the processes, use fans or air conditioning, use physical barriers that reduce exposure to radiant heat. Providing periodic breaks and rest facilities in cooler conditions and by circulating cool drinking water for the workers prevents them from dehydration. Allow the workers to work in shifts so that they may not be fully exposed to the humid conditions. Provide suitable personal protective equipment’s to the workers. Prevent employees who are more susceptible to heat stress either because of an illness or medications that may encourage the early onset of heat stress. Working on Height – Fragile Roofs / Roofs (Can be asked in both ways, control measures will be almost same in both)
Hazards – Fragile Roofs
Fall from roof edges
Fall through fragile roof sheet.
Fall through openings in the roof
Hot Bitumen (Coal tar) material when using it.
Material Fall from height
1) Provide edge protection around the roof perimeter
2) Cover or guard the openings on the roof
3) Use crawler board on slope fragile roof
4) Provide proper access and egress to the roof
5) Tie safety net below the roof
Protections for preventing material fall from height:
1) Materials shall be lowered from height, no material shall be dropped.
2) Do not keep any loose materials unsecured on the roof
3) Tie the tools used for roof work to the waist
4) Sheets shall be secured and kept on roof.
1) All employees should appropriate PPEs like Safety helmet, gloves, Safety Harness etc.
2) They shall wear spectacles when working under hot sun on a GI sheet work. Employees:
1) Employees send for the roof work should be selected and trained
2) Employees selected for the job should undergo premedical test.
3) Establish Height work permit
4) Appropriate rest pause should be introduced.