HighHot mix asphalt is maintained at 150-180°C during transport and discharge, a temperature that causes immediate full-thickness burns upon skin contact. Workers face burn risks during truck loading when material is discharged from plant bins, during transport if material splashes from inadequately secured tarpaulins, and especially during discharge operations when material flows from the truck body into pavers or onto the ground. Bitumen's viscous nature causes it to adhere to skin, clothing, and safety equipment, continuing to burn tissue as it cools. Unlike burns from hot water that can be quickly removed, bitumen bonds to skin and attempting removal causes additional tissue damage. Burns commonly affect hands and forearms when workers guide material flow, face and eyes when unexpected splashes occur during discharge, and legs and feet if workers step in spilled material. The severity of injury depends on contact temperature, duration, and surface area affected, with even small burns requiring specialised medical treatment at hospital burn units.
Consequence: Full-thickness burns causing permanent scarring, tissue damage requiring skin grafts, prolonged hospitalisation, permanent disability affecting hand function, or fatal injuries if large body surface areas are affected.
MediumHot asphalt releases complex mixtures of organic compounds as fumes when heated, including polycyclic aromatic hydrocarbons (PAHs), hydrogen sulphide, sulphur dioxide, and other volatile organic compounds. Fume generation increases with temperature and during discharge operations when material is agitated and exposed to air. Workers in the immediate vicinity of discharge points experience the highest exposures, particularly in calm weather conditions when fumes do not disperse rapidly. Short-term exposure causes eye, nose, and throat irritation, headaches, nausea, and dizziness affecting worker performance and potentially causing incidents if cognitive function is impaired. Chronic exposure has been associated with respiratory sensitisation, with some studies suggesting potential long-term health effects from PAH exposure. Truck drivers experience repeated exposure during multiple daily deliveries, with cumulative exposure depending on delivery frequency, site ventilation conditions, and duration spent near discharge points. Enclosed operator cabins provide some protection but drivers must often exit vehicles to coordinate discharge operations, entering high-exposure zones.
Consequence: Acute respiratory irritation causing immediate discomfort, headaches affecting work performance, potential respiratory sensitisation from chronic exposure, or long-term health effects from repeated PAH exposure over career duration.
MediumRepeated skin contact with bitumen and asphalt products causes occupational dermatitis affecting primarily hands and forearms. Bitumen acts as a skin irritant, and some workers develop allergic sensitisation after repeated exposure. Drivers who handle contaminated equipment, clean truck bodies, or work with bitumen-covered tools experience chronic low-level exposure. Bitumen contamination on gloves, clothing, and equipment creates ongoing contact hazard even after work activities have ceased. The condition presents as red, itchy, inflamed skin that may crack and bleed, increasing risk of secondary infections. Workers who develop sensitisation may experience increasingly severe reactions with each exposure, potentially requiring removal from asphalt work entirely. Hand dermatitis affects grip strength and manual dexterity, increasing risk of other incidents when workers cannot properly handle tools or equipment. The chronic nature of the condition affects quality of life beyond working hours, with sleep disruption from itching and appearance-related psychological impacts.
Consequence: Chronic skin inflammation requiring ongoing medical treatment, development of allergic sensitisation necessitating job modification, secondary infections from cracked skin, or permanent dermatitis requiring complete removal from bitumen work.
HighHot asphalt trucks are heavy vehicles typically weighing 40-50 tonnes when loaded, operating in congested construction sites with limited manoeuvrability and rear visibility. Reversing operations to position at discharge points create high risk of striking workers, site personnel, or public who may enter the vehicle's path unnoticed by the driver despite mirrors and reversing cameras. Trucks often operate on freshly prepared surfaces that may be unstable or have insufficient bearing capacity for heavy vehicle loads, creating risk of bogging or lateral movement. Tipping operations shift the vehicle's centre of gravity rearward and upward, creating roll-over risk if conducted on sloping ground or soft surfaces. Overhead powerlines present electrocution hazard when tipping bodies are raised, particularly in urban environments where utility clearances may be limited. Traffic management changes frequently in active road construction, with lane configurations, barriers, and personnel positions changing between deliveries, requiring drivers to reassess site conditions for each entry. High engine noise, site background noise from other equipment, and radio communications interfere with driver awareness of verbal warnings from ground personnel.
Consequence: Fatal or severe injuries to workers or public struck by reversing vehicles, electrocution from contact with overhead powerlines during tipping, vehicle roll-over causing driver injury and material spillage, or traffic incidents involving public vehicles entering work zones.
MediumUncontrolled discharge or spillage of hot asphalt creates multiple hazards including thermal burns from walking through spilled material, environmental contamination if bitumen enters stormwater systems or waterways, and traffic hazards if material extends onto public roads. Spillage can occur from overloading causing material to overflow during transport, mechanical failure of truck tipping mechanisms causing uncontrolled discharge, or operator error during discharge positioning. Spilled bitumen quickly adheres to surfaces and is extremely difficult to remove, with cleanup requiring specialised equipment and trained personnel. When hot bitumen enters stormwater systems, it can cause blockages and release toxic compounds as it cools and breaks down. Discharge onto unsealed surfaces creates lasting contamination requiring soil excavation and disposal as hazardous waste. Spillage onto traffic lanes creates immediate hazard for public vehicles that may lose traction on bitumen-covered surfaces. Cleanup operations expose workers to thermal and chemical hazards as they handle contaminated materials, often under time pressure to restore traffic flow.
Consequence: Environmental prosecution for bitumen discharge to waterways, costly remediation of contaminated soil, public safety incidents from bitumen on traffic lanes, or worker injuries during emergency cleanup operations.
