Element 12 - Demolition & Deconstruction Flashcards
Define “Demolition”?
Demolition involves knocking down buildings to clear ground, dismantling parts of structures or the removal of walls.
Identify some typical demolition hazards?
- Premature collapse of structures.
- Work at height.
- Plant and machinery.
- Contact with live overhead cables.
- Contact with buried services.
- Asbestos.
- Dust.
- Movement of vehicles.
- Explosives.
- Noise and vibration.
- Hazardous substances.
- Biological hazards from vermin or stagnant water.
- Sharp objects (glass, nails, syringes, etc).
- Manual handling.
Give some typical safety control measures for demolition?
- Careful assessment of demolition method (keep workers away from the immediate area).
- Elimination or control of work at height.
- Structural surveys to assess strength and stability of structures.
- Propping or supporting might be necessary.
- Assess strength of floors (do they support plant and machinery).
- Disconnect services (electricity, gas, water).
- Removal and disposal of hazardous materials.
- Securing of the site (fencing/hoarding to create a buffer zone and exclude unauthorised access).
- Damping down with water spray to reduce dust.
Define DECONSTRUCTION?
Often also referred to as “dismantling”, is the taking down of all, or a substantial part of a structure (often for re-use).
Give some Demolition and Deconstruction methods?
- Piecemeal Demolition
- Deliberate Controlled Collapse
- Pre-Weakening
- Progressive Demolition
- Overturning by Wire Rope Pulling
Identify the 2 TYPES of Equipment that are used during Demolition and Deconstruction?
- Hand Tools
- Use of Machines
Give examples of machines used for Demolition?
- Demolition Balls
- Impact Hammers
- 360 degree Excavator
- Hydraulic Pusher Arm
- Shears
Explain how EXCLUSION ZONES can be determined?
- Plan Area (area to be demolished)
- Designed Drop Area (immediate hazard area where most of collapse of structure will occur)
- Predicted Debris Area
- Buffer area (allowing for unpredictable events)
List the causes of falling materials?
- Deliberate dropping
- Materials falling or being ejected from the apertures
- Inadvertent falls of dislodged material
- Materials acting as a projectile
- Falling loads or equipment
- Lifting loads over areas of public access
Unplanned falls of material, including accidental falls of tools and materials
Define DELIBERATE DROPPING?
In demolition, deliberate dropping refers to deliberate pulling down or knocking over of a structure
Describe how transport-related accidents in demolition work occur?
- Poor, unstable and uneven ground
- Poor control of vehicle movements
- Use of unsuitable plant or vehicles
- Unauthorised use of vehicles and plant by untrained operators
- The potential proximity of private or road-going trade vehicles to heavy demolition plant
- Vehicles left in unplanned areas, causing obstructions and obscuring sight lines
List some hazards relating to Demolition and Deconstruction?
- Premature Collapse
- Falls and Falling Materials
- Plant, Vehicles and Other Equipment Overturning
- Manual Handling
- Dust and Fumes
- Noise and Vibration
- Existence of Services
- Hazardous Substances
- Dilapidation
Give some general control measures for Demolition work?
- Avoidance of Premature Collapse
- Protection from Falls and Falling Material
- Siting and Use of Plant, Vehicles and Other Equipment
- Protection against Dust and Fume
- Precautions to avoid Noise and Vibration
- Protection of the Environment
- Competence of the Workforce
Define a BUTTRESS?
An inclined tube assembly anchored at one end (on the ground or other suitable point) and fitted to the scaffold at the other, to widen the structure base and increase stability
Give two methods of avoiding Premature Collapse?
- Temporary Structural Supports
- Facade Retention Systems
