Demolition & Deconstruction Flashcards
What methods of Demolition are there?
• Piecemeal- hand held tools gradually reduce ground level
• Deliberate controlled collapse- explosive or pre weakening followed by remote mechanical demo or pulling using wire rope.
• Pre weakening
• Progressive
• Overturning wire rope pulling.
Common causes of transport related accidents in demo work?
• Poor unstable & uneven ground.
• Poor control of vehicle movements
• Use of unsuitable plant or vehicle’s
• Unauthorised use of plant by untrained operators
• Proximity of private road going trade vehicles to heavy demo plant.
• Vehicles left in unplanned areas, causing obstruction & obscuring sight lines
With regard to hazardous substances what three significant areas outlined in method statement & demo plan.
• How the presence of hazardous substances is to be identified
• Means of disposal
• PPE requirements
How is premature collapse avoided during demolition?
Designers should consider:
• How stability can be maintained & include relevant information
• Temporary scaffold support
• Temporary structures designed to take relevant loads
• The effects structurally by removing certain parts
• Shoring, propping, façade retention, buttresses
• Supports in position prior to removal
• on sound base
• Adequately laced & braced
• can resist dynamic loads
• checked prior and during (vibration)
What protection measures used for noise during demolition?
• Noise assessment to identify noise sensitive areas
• Monitor background noise prior to work at noise sensitive areas
• State actions taken to reduce noise
• Use plant & equipment with low operating noise levels & mains electricity in preference to diesel
• Solid panelled fence not wire
• restrict deliveries to daytime working hours.
• Display project contact details prominently in residential areas to all nuisance issues to be addressed quickly
• Warning signs to keep people away from danger area
• Fit appropriate silencing/ soundproofing to all machinery & plant
• Provide adequate hearing protection
What protection used for dust control on demo sites?
• A COSHH assessment
• Maintaining high standard of housekeeping, regularly cleaning and sweeping site roads
• Using techniques that produce low levels dust - damping down
• Designing vehicle routes to & from site to limit problem
• Maintaining plant- emit fewer pollutants & prevent spillage of oil & fuel
• Wheel wash facilities
• water sprays as suppressant mindful of elec/ pollutants
• Air movers or LEV
• Covered wagons & skips
• PPE
• Asbestos & lead samples etc
What precautions put in place to ensure safe siting of plant & machinery on demo site?
• Properly sited within compound & isolated or immobilised end of each shift
• Suitable parking areas for all vehicles
• Not left in unplanned areas
• Safe loading & unloading areas skips/vehicles
• Prevent parking near scaffolding, material stacks, compressed gas or storage compounds containing toxic or flammable materials especially transport carrying LPG
How is environment protected during demolition process?
Environment info relating to underground tanks or potential chemical biological hazards or presence of contaminated land & buildings former use supplied to contractor prior.
Protection required from Noise. Dust waste & asbestos.
All info included In health & safety plan of project
How do you ensure competence of demolition work force?
• All staff should be competent for tasks they undertake
• CDM regs places responsibilities on client & other persons involved to ensure competent persons employed on project.
• Management should ensure necessary competencies & developed by training.
• In case of subcontractors a H&S policy, suitability of method statements & previous work & accident history, quality of risk assessment & level of training of staff a good guide.
• CITB certification
• Further enhanced by induction or other training covering hazards & legislation involved in demolition. Eg. NVQ’s
What information considered in pre demolition survey?
• Presence of asbestos, types & location
• Identification of key structural elements including pre & post tensioned components
• Types of services & locations
• Identification, significance & extent of any dilapidation of structure
• Review of drawings, structural calculations & existing health & safety file relating to structure.
• Review of historic structural alterations
What type of information is contained in demolition method statement?
• Name & address of demolition contractor on site
• Sequence & method of demolition
• Details of personnel access, working platforms & machinery requirements
• Details of any pre weakening of structures to be pulled down or demolish using explosives & temporary propping required
• Arrangements for protecting workers, public & exclusion of unauthorised people from work area
• Site security including provision of fencing, barriers controlling of spectators or site visitors, use of exclusion zones & containment of demolition materials
• Details of removal or isolation of electrical gas & other services
• Details of temporary services required & welfare services provided
• Arrangements for disposal of waste
• Details of environmental considerations
• Details of COSHH controls & flammable substances
• Any permit to work system
• Arrangements for control & coordination of site transport, contractors & storage.
• Training requirements & competencies of personnel involved in demolition processes
• Identification of people with special responsibilities for coordination & control of safety & emergency procedures/ arrangements
List type of emergency arrangements demolition contractor consider?
• Containing localised chemical spillage or gas/ vapour release
• Dealing with emergencies caused by damage to utility supplies not isolated particularly gas explosion
• Fire evacuation
• Plans to deal with premature or unplanned collapse of structures
• Rescue of persons trapped under collapsed structures
• Recovery of persons fallen from height
• Rescue of persons fallen into cellars pits voids
• First aid treatment
