Asbestos Fibre Release and Inhalation During Removal of Asbestos-Containing Roofing
HighThe most serious health hazard in roofing removal is exposure to asbestos fibres released during dismantling of asbestos-containing materials common in roofs constructed before 1990. Asbestos cement sheeting, corrugated asbestos roofing, and asbestos-containing underlays were extensively used in Australian construction and remain present in millions of existing buildings. Disturbance of these materials through removal, cutting, drilling, breaking, or simply walking on deteriorated asbestos roofing releases microscopic asbestos fibres that, when inhaled, cause fatal diseases including mesothelioma, asbestosis, and lung cancer developing 20 to 50 years after exposure. Workers may not recognize asbestos materials particularly where they are painted over, concealed beneath later additions, or resemble non-asbestos products. The outdoor elevated working position can create false assumption that fibre dispersal reduces risk, but safe exposure thresholds do not exist for asbestos. Dry removal methods including breaking, cutting with power tools, or high-pressure cleaning generate extremely high fibre concentrations. Even wetting and careful handling release fibres requiring respiratory protection. Contamination of workers' clothing, hair, and skin allows fibres to be transported from work sites to homes and vehicles, creating secondary exposure for families. The long latency period between exposure and disease onset means workers may not recognize the seriousness of exposures until decades later when fatal disease develops.
Consequence: Mesothelioma, an aggressive fatal cancer of lung lining with no cure and survival typically 12-18 months after diagnosis, asbestosis causing progressive lung scarring and respiratory failure, lung cancer, and asbestos-related pleural disease causing breathing difficulty. Secondary exposure of family members from contaminated clothing causing disease in people who never worked with asbestos.
Structural Collapse of Deteriorated Roof Frames During Material Removal
HighRoof structures scheduled for removal or re-covering are often deteriorated from age, water penetration, termite damage, or structural overloading, creating serious collapse risks when roofing materials are removed. The existing roof covering provides bracing and load distribution that maintains marginal structural stability, but removal of sheeting or tiles eliminates this bracing effect and can trigger sudden collapse of weakened structures. Timber roof frames may have extensive termite damage, wet rot from long-term water penetration, or undersized members that were marginally adequate when new but have deteriorated over decades. Steel roof structures may have severe rust perforation reducing load capacity. Previous modifications including removal of structural members, addition of heavy equipment loads, or alterations to load paths may have compromised integrity. Workers operating on roof structures during removal have limited visibility of structural condition from above and may not recognize warning signs of impending failure. Progressive removal creates constantly changing load distributions that can trigger collapse without warning. Partially dismantled structures have reduced redundancy meaning failure of any single member can initiate progressive collapse affecting large roof areas. Workers can fall through collapsing structures or be struck by falling structural members, beams, and roofing materials.
Consequence: Fatal or catastrophic injuries from falls through collapsing roof structures, crushing injuries from being struck by falling beams and structural members, secondary falls to ground level through multiple roof levels in multi-storey buildings, and traumatic injuries from impacts during uncontrolled descent through failing structures.
Falls Through Fragile or Absent Roof Surfaces During Removal Operations
HighAs roof removal progresses, increasing areas of roof surface become fragile, partially removed, or completely absent, creating serious fall-through hazards for workers who must traverse these areas to access remaining work. Deteriorated roofing materials including old corrugated iron, weathered fibro cement, and aged tiles can collapse without warning when workers step on them. Battens and sarking materials may be rotten or termite-damaged and unable to support worker weight. Once roofing materials are removed, only exposed battens or structural members remain, creating large voids between load-bearing elements where workers can fall through to ceiling spaces or lower levels. Workers focused on physically demanding removal tasks may not maintain awareness of fragile surfaces and absent areas. Debris, removed fixings, and off-cuts create trip hazards causing workers to lose balance and fall through fragile adjacent areas. Night work or work in low light conditions reduces visibility of hazardous surface conditions. Renovation work where only portions of roof are removed creates patchwork of removed and intact areas where boundaries between safe and fragile surfaces are not clearly defined. Unlike new installation work where roof surfaces progressively become more stable as materials are added, removal work creates progressively more hazardous working surfaces as materials are stripped away.
Consequence: Falls through fragile roof materials or absent surfaces causing impacts onto ceiling joists, ductwork, or insulation materials in ceiling spaces, potential falls continuing through ceiling materials to lower building levels, serious impact injuries including fractures and head trauma, and potential fatalities from falls of two metres or greater particularly in multi-storey buildings.
Falling Objects and Materials Striking Workers or Public Below Removal Areas
HighRoof removal generates substantial quantities of falling debris including removed roofing sheets, tiles, battens, fixings, and broken materials that pose serious hazards to anyone in areas below work zones. Metal roofing sheets being removed are large, unwieldy, and act as sails in wind conditions making controlled handling difficult. Dropping a metal sheet from roof height creates a heavy falling object that can cause fatal head injuries or crush injuries to anyone struck. Roof tiles weigh 4 to 5 kilograms each and falling from heights of 5 to 10 metres achieve significant impact energy. Bundles of tiles can shift during handling and cascade off roof edges. Removed battens and structural members falling from height become dangerous projectiles. Small items including screws, nails, broken tile pieces, and debris continuously rain down from removal operations. Wind can catch partially detached roofing materials tearing them free and propelling them unpredictably. Workers on lower roof levels, scaffolding, or ground are exposed to falling object risks throughout removal operations. Members of public including building occupants, pedestrians, and neighbouring property users can be struck by materials falling beyond exclusion zone boundaries. Vehicles parked near buildings can be damaged by falling materials. The chaotic nature of demolition work with materials being removed from random locations rather than systematic sequences increases unpredictability of falling object hazards.
Consequence: Fatal head injuries from being struck by falling roofing sheets, tiles, or structural members, crush injuries to feet and lower legs from dropped materials, lacerations from sharp metal edges or broken tiles, property damage to vehicles and structures, and injuries to members of public requiring emergency response and creating significant liability.
Lacerations and Puncture Wounds from Sharp Edges, Nails, and Broken Materials
MediumRoof removal work involves handling materials with extremely sharp edges including cut metal sheeting, broken tiles, and weathered fibro cement with fractured edges sharper than new materials. Old roofing materials become brittle with age and fracture during removal revealing razor-sharp broken edges. Metal roofing corroded over decades develops sharp rust perforations and edges. Removal of fixings leaves exposed nail points and screw tips protruding from battens and through removed materials. Workers handling materials during dismantling, passing materials to other workers, and loading materials for disposal sustain cuts and punctures to hands, arms, and legs. Gloves worn during removal operations become contaminated with dirt, rust, and debris increasing infection risk from wounds. Tetanus infection risk is significant as roof materials and accumulated debris often contain soil bacteria and contamination from bird and rodent droppings. Removed roofing materials with protruding nails create serious puncture hazards during stacking, loading, and transport. Workers stepping on removed materials or debris can sustain puncture wounds through boot soles if penetration-resistant footwear is not worn. Corroded fixings may break during removal causing sudden hand and tool movement striking adjacent sharp edges or structural members.
Consequence: Deep lacerations requiring sutures or surgical repair, puncture wounds causing infections including tetanus if immunization is not current, contaminated wounds from rust and debris requiring antibiotic treatment, eye injuries from metal fragments and dust during removal operations, and potential loss of work time for wound healing and treatment.
Uncontrolled Descent and Loss of Balance on Sloped Deteriorated Roof Surfaces
HighRoof removal operations occur on sloped surfaces that are often deteriorated, contaminated with debris, and progressively destabilized as materials are removed, creating serious fall and sliding hazards. Unlike new roof installation where workers operate on progressively more stable and complete surfaces, removal work creates increasingly unstable working conditions as materials are stripped away. Slopes that provided adequate grip when roof coverings were intact become extremely slippery when only deteriorated battens or structural members remain. Decades of accumulated debris including dust, leaves, bird droppings, and moss create slippery contamination layers. Morning dew or rain makes surfaces treacherously slippery. Workers carrying heavy removed materials or pulling against corroded fixings can lose balance and slide down slopes toward unprotected edges. Physical fatigue from demanding removal work reduces strength and coordination. The repetitive nature of removal tasks can reduce vigilance about foot placement and edge proximity. Unexpected structural failures or sudden release of adhered materials can destabilize workers. Working backward or in awkward positions to access fixings or dislodge materials prevents optimal balance and stability.
Consequence: Uncontrolled slides down roof slopes resulting in falls from eaves, impact injuries from striking obstacles during descent, lacerations from sliding across sharp materials or exposed fixings, and potential fatal falls from roof edges if edge protection is inadequate or if workers slide under or through barrier gaps.
