What this SWMS covers
Tipper and dog combinations consist of a rigid tipper truck (prime mover with integral tipping body) coupled to a tipping dog trailer via drawbar connection, creating multi-body vehicle combinations capable of carrying 20-40 tonnes of bulk materials depending on configuration and regulatory limits. The tipper body configuration uses hydraulic rams to raise the front of the body while material slides out the open tailgate under gravity. Dog trailers are non-articulated trailers connecting via drawbar rather than fifth-wheel coupling, with the trailer supported at front by turntable on truck rear and at rear by trailer axle group. This configuration provides excellent stability for heavy bulk materials and allows both truck and trailer bodies to tip independently. Tipper and dog operations are fundamental to construction material supply, transporting bulk aggregates including crushed rock, sand, gravel, and road base, bulk earthworks materials for site cut and fill operations, demolition waste and construction debris for disposal, imported fill materials and select materials, asphalt and concrete products, and bulk landscaping materials including topsoil and mulch. The tipper discharge method allows rapid unloading without requiring external equipment like cranes or forklifts, making it efficient for high-volume material movements. However, the tipping process creates significant hazards including overhead power line contact when bodies are raised, vehicle instability and potential rollover when tipping on slopes or soft ground, material avalanche when tailgates open on cohesive or frozen materials, and struck-by hazards to workers in discharge areas. Tipping operations require careful site assessment and positioning to ensure vehicle stability and clearance from overhead hazards. Drivers must verify ground bearing capacity supports concentrated loads from tipping forces, identify overhead power lines, tree branches, scaffolding, crane jibs, and building structures, ensure adequate clearance exists when body is fully raised typically 6-8 metres total height, position vehicle level avoiding cross-slopes that could cause rollover during tipping, and establish exclusion zones preventing workers from approaching raised tipper bodies. The hydraulic tipping mechanism creates crush points between body and chassis, with additional pinch hazards at tailgate hinge points. Material may not discharge cleanly, requiring drivers to rock loads by partially lowering and re-raising bodies, or in extreme cases, manual intervention to break up bridged materials presenting additional hazards. Load securing during transport is critical as unsecured bulk materials can shift causing vehicle instability, spillage on roadways creating hazards for other traffic, and overloading of individual axles exceeding legal limits. Materials must be contained within body height limits, covered with tarps if required to prevent spillage, and loaded to achieve legal axle weight distribution without exceeding gross vehicle mass. Cohesive materials like clay may stick to body sides and floor rather than discharging cleanly, requiring manual cleaning between loads. Abrasive materials accelerate wear on body floors and tailgates requiring regular inspection and maintenance. Wet or frozen materials increase weight and may not flow during tipping, creating difficult discharge scenarios. Construction site operations involve navigating rough temporary access roads, steep grades, tight turning areas, and congested work zones with multiple contractors and mobile plant. Tipper and dog combinations have restricted manoeuvrability compared to articulated vehicles, requiring wider turning radii and greater swept path clearance. The drawbar coupling can jackknife if excessive angle develops during reversing or tight turns. Loaded combinations require extended braking distances particularly on downhill grades or in wet conditions. Site personnel may not recognize tipper discharge hazards including material slide area, raised body instability, and overhead clearance requirements, necessitating clear communication and exclusion zone enforcement during tipping operations. Australian regulations governing tipper operations include Heavy Vehicle National Law mass and dimension requirements, Chain of Responsibility obligations for load security and vehicle roadworthiness, WHS requirements for controlling tipping hazards and protecting workers in discharge areas, electrical safety regulations regarding clearances from overhead power lines, and environmental requirements for containing loads and preventing spillage. Drivers must hold appropriate heavy vehicle licence class (HR minimum for rigid tippers, HC if combination exceeds 4.5 tonne trailer), with demonstrated competency in load calculation, safe tipping procedures, overhead hazard recognition, and site access planning. The high-consequence potential of tipper incidents including power line contacts causing electrocution, vehicle rollovers during tipping, and workers struck by tipping bodies makes rigorous risk assessment and documented safe operating procedures essential for all tipper and dog operations in construction environments.
Fully editable, audit-ready, and aligned to Australian WHS standards.
