Construction and Works of a temporary nature - Hazards and Controls Flashcards
Range of Construction Activities
Site Clearance Demolition and Dismantling Excavation Loading, unloading and storage of materials Vehicle movements Fabrication Decoration Cleaning Site Services - Utilities Landscaping
Particular construction issues
Transitory nature of workers
Temporary nature of construction activities and the constantly changing workplace
Time pressure
Weather conditions
Literacy, numeracy and language
Regulations covering Construction Projects
Construction (Design and Management) Regulations 2015 - CDM
What all construction projects must have
Workers with the right skills, knowledge, training and experience
Contractors providing appropriate supervision, instruction and information
A written construction phase plan
What projects with more than one contractor must have
All for construction projects plus:
Principal designer and principal contractor must be appointed
Needs a health and safety file
When must client notify the HSE
If the project lasts longer than 30 days and has more than 20 workers or exceeds 500 person days
Types of duty holder under CDM
1) Clients
2) Domestic Clients
3) Designers
4) Principal Designers
5) Principal Contractors
6) Workers
Principal Designer responsibilities
Plan, manage and coordinate H&S in the pre-construction phase of a project, including identifying. eliminating and controlling risks and ensuring the designers carry out their duties
Principal Contractor responsibilities
Plan, manage and coordinate H&S in the construction phase of a project, including:
Liaising with client and principal designer
Preparing construction phase plan
Organising cooperation between contractors and coordinating their work
Pre-Construction Information
Provides the H&S info needed in advance of work and is used to prep the construction phase plan.
Provided by the client and contains things like H&S file, Asbestos surveys etc…
Info must be relevant to the project and have appropriate level of detail and be proportionate to the nature of the risk
Construction Phase Plan
Outlines:
H&S arrangements for managing significant H&S risks associated with the project
The site rules
Any specific measures concerning work listed in CDM as involving particular risks
Client must ensure it is in place before the work begins
Works under CDM which involve particular risks
Risk of burial under earth, engulfment or falling from height
Risk from chemical or biological hazard
Ionising radiation work in controlled areas
Near high voltage power lines
Exposure to risk of drowning
Work on wells, underground earthworks and tunnels
Divers using a system of air supply
Workers in cassions with a compressed air atmosphere
Involving explosives
Assembly or dismantling of heavy prefabricated components
Who preps the Construction Phase Plan
Single-contractor projects it is the Contractor
Multi-contractor projects it is the Principal Contractors duty
Health and Safety File
Must contain info about the project likely to be needed to ensure H&S
Only required from projects with more than one contractor
Should be clear, concise and easily understandable in a conveniently accessible format
General site security precautions
Perimeter fencing with adequate signage and lighting
Doors and gates
Storage compounds and facilities for plant, hazardous and dangerous substances
Height of perimeter fencing
2m
What should be included in site inductions
Signing in/out arrangements Fitness to work / alcohol / drug screening procedures Parking and site traffic rules PPE requirements Working conditions on site Emergency procedures Use of mobiles, smoking Specific PTW requirements Use of welfare facilities
Regulations covering Height
Working at Height Regs 2005
Examples of Working at Height
Gutter cleaning Putting up a display Minor roof work Shelf stacking Window cleaning Unloading a vehicle Machine maintenance
Hierarchy for managing work at height
Avoid where possible
Use work equipment or other measures to prevent falls
Use work equipment or other measures to minimise distance and consequence of falls
Priority of preventing falls
Prevention over consequence limitation
Collective measures over personal protective measures
Passive preferred to active measures
Fall prevention equipment
Guard rails
Work restraints
Fall Arrest equipment
Lanyard and shock absorber
Landing systems
Types of common access equipment
Ladders and step ladders
Trestles and staging platforms
Independent tied scaffolds
Mobile tower scaffolds
Hazards of using ladders and stepladders
Overloading - Exceeding the max weight of the ladder
Overreaching - body not remaining between stiles and not having both feet on the same rung
Selecting a ladder
Suitable for worst case surface conditions
Suitable for task/environment
Class 1 ladders for work
Suitable size
Used with manufacturers recommended stability devices
Securing a ladder
Tie to suitable point
Use a ladder stability device if tie off not possible
Last resort, foot the ladder
Training for using ladders
Users should be trained and instructed to use equipment with the following rules:
1) ensure the ladder is long enough
2) ensure rungs or steps are level for use
3) ensure weather is suitable
4) wear robust sensible footwear
5) Know how to prevent members of the public using them
6) Know that certain medical conditions or drugs could stop them using them
7) Know how to tie it properly
Independent tied scaffold
Made of 2 rows of standards both internal and external.
Is tied to a building being worked on
Main hazards associated with scaffolds
Collapse
People falling from the scaffold
Objects falling or being dropped
People walking into it
Statutory inspection of scaffolds
Immediately after construction
Before anyone goes on it
After and incident that may have damaged it
Every 7 days
Inspection must be done by a competent person,
Written report should be made following the inspection
Falsework
Any temporary structure used to support a permanents structure while it is not self-supporting, either in new construction or refurb
Approved methods of mobile scaffold tower construction
Advance guard rail system
Through the trap systems
Inspection of mobile tower scaffolds less than 2m high
After assembly in any position
After an event liable to have affected stability
At suitable intervals
Inspection of mobile tower scaffolds more than 2m high
After assembly in any position
After an event liable to have affected stability
At intervals not exceeding 7 days
Types of temporary access
Suspended access cradles
Work positioning systems
Boatswains Chairs
Rope access techniques
Definition of a fragile roof
Would be liable to fail if reasonably foreseeable loading were applied to it
Demolition - Pre-demo surveys
Structural Survey
Hazardous Substance Survey
Site/Environmental Survey
Soft stripping
Removal of non-structural components
Hard stripping
Salvage of structural components
Types (principals) of demolition
Piecemeal (progressive) demolition
Controlled (deliberate) demolition
Pre-weakening through deliberate removal of structural components
Demolition techniques
By hand
By machine
By explosive
By other means
Demolition equipment
Base machine
Equipment - boom and dipper arm
Attachments - various
Demolition equipment - hydraulic attachments
Pusher arm Impact hammer Hydraulic shears Pulveriser Demolition pole Grapple Multi-purpose
Demolition equipment - non-hydraulic attachments
Ball
Wire rope pulling
Drilling and sawing
Main safety hazards of demolition
Premature collapse Falling materials Falling from height Impact from site vehicle movements Mechanical hazards Fire and explosion hazards Confined spaces
Main health hazards of demolition
Chemical
Physical
Biological
Exclusion zone
3D space from which all persons including the public are excluded during demolition activities
Hazards associated with excavations
Ground movement / collapse of sites Surcharging Ground and surface water Stability of adjacent structures / services Underground services Overhead lines People falling in Plant falling in Materials falling in Toxic gas and oxygen deficiency Biological and chemical hazards Noise and vibration
Ground controls for excavation
Battering or stepping
Supports
Surcharging
Occurs when plant or material is near the side of the excavation and increases the horizontal load causing walls to collapse
Controls for Surcharging
Barriers and signs to keep vehicles away
Stop blocks for tipping vehicles
Materials stored away from excavation
Controls for ground water
Water is channelled into sumps and removed using hydraulic pumps
Controls for stability of adjacent structures / services
Shoring of structures
Supporting of services
Hazards of underground services
Electricity cables can result in explosion or burns
Escaping gas can ignite
High pressure water pipes, sewers, telecoms all pose specific hazards
Controls for underground services
Check existing plans
Use Cable Avoidance Tools
Appropriate digging techniques
When do most fatal injuries with excavators occur
When moving - strikes a pedestrian
When slewing - Trapping a person between plant and fixed structure or vehicle
When working - When moving the bucket or other attachment strikes a person or if the bucket falls from the excavator
5 precautions to control the risk of using excavators
1) Exclusion
2) Clearance
3) Visibility
4) Signaller
5) Bucket attachment
3 categories of worker who must be trained and competent for excavator works
1) Driver
2) Signallers
3) Pedestrians
Quick hitches or Quick Couplers
Latching device that enables attachments to be connected to the dipper arm of an excavator and changed quickly
Trenchless Technology - Horizontal Directional Drilling
Uses curved trajectory to enable a pipeline to pass under an obstacle such as a river or a road without the need for excavation
Trenchless Technology - Impact Moling
Uses pneumatic piercing tool to create a bore hole. The approach compacts and displaces the soil rather than excavating and removing it, so minimises the disruption to the soil
Trenchless Technology - Pipe Bursting
Can be used to replace existing or damaged pipeline with a new pipeline of the same diameter. The old pipeline is burst in-situ or removed piece by piece and broken up as it is pushed out the tunnel
Statutory inspections of excavation, equipment and materials
1) At start of the shift
2) After any event likely to haver affected strength of the excavation
3) After any material unintentionally falls or is dislodged
Requirements to report statutory inspections
Report must be made under Reg 24 of CDM
1 report needed every 7 day period
Must be retained at site and available for HSE inspectors
Retained until work is finished and a further 3 months afterwards
