Concrete Slab on Ground Safe Work Method Statement

Slab construction requires extensive manual handling of steel reinforcement mesh, reinforcement bars, formwork timber, fill materials, and concrete finishing tools. Standard SL72 mesh sheets measure 2.4m x 6.0m and weigh approximately 25kg, requiring two-person lift and carry across potentially uneven fill surfaces. Reinforcement bars in thickened beams come in 6-metre lengths weighing 15-20kg each, stored in bundles that can exceed 100kg requiring mechanical lifting or careful manual debundling. Steel fixers work in sustained awkward postures kneeling and bending to tie mesh intersections and install bar chairs, with typical residential slab requiring 200-400 ties creating cumulative strain on lower back and knees. Concrete finishing work requires prolonged kneeling during bull floating, extended forward bending during power troweling, and sustained squatting or kneeling during edge finishing and joint cutting. Large commercial slabs may require 8-12 hours continuous finishing work without adequate breaks due to concrete setting time constraints.

Consequence: Acute lower back strain requiring immediate medical attention and extended time off work, chronic back conditions including disc degeneration creating permanent disability, knee damage from sustained kneeling on hard rough surfaces, shoulder impingement from repetitive overhead work placing bar chairs, hernias from lifting excessive loads, and accumulated musculoskeletal disorders shortening working careers in the concreting trade.

Wet concrete contains Portland cement creating highly alkaline conditions with pH 12-13 that causes progressive chemical burns through skin contact. Concrete finishing requires workers to kneel and place hands in wet concrete during screeding, floating, and edging operations. Concrete that penetrates gloves or enters boots through top openings creates sustained skin contact for hours. The chemical burn develops slowly - workers often notice only mild irritation initially but serious burns develop over 4-8 hours of exposure. Traditional cotton or fabric gloves absorb cement water increasing exposure, while disposable nitrile gloves tear easily in abrasive concrete. Kneeling in wet concrete during finishing allows penetration through clothing reaching knees and lower legs. Workers who develop cement dermatitis through repeated exposure can become permanently sensitized, experiencing severe reactions to even minor cement contact making future work in concreting impossible.

Consequence: Painful chemical burns requiring medical treatment and debridement of dead skin tissue, infection risk from open wounds exposed to worksite contaminants, permanent scarring from deep burns, development of cement dermatitis with chronically painful cracked bleeding skin on hands and forearms, allergic sensitization preventing future work with cement products, and career-ending disability for workers who become allergic to cement creating substantial workers compensation liabilities.

Concrete delivery involves multiple concrete trucks weighing 20-30 tonnes reversing into residential driveways and construction sites with limited space and visibility. Drivers have restricted rear vision even with cameras and reversing alarms, while multiple workers operate around trucks during concrete discharge. Concrete trucks must position chute over formwork, requiring reversing close to excavations and workers. Boom pumps used for larger slabs or difficult access extend booms 15-30 metres positioning concrete hose over slab, creating struck-by hazards during boom movements. Pump operators have limited visibility of work areas beneath boom requiring radio communication with placement crew. Hose whip during pumping creates impact forces sufficient to knock workers down, while hose disconnection can discharge high-pressure concrete striking nearby personnel. Workers concentrate on concrete placement and finishing becoming unaware of moving vehicles and equipment around them.

Consequence: Fatal crushing injuries if worker struck by reversing concrete truck, serious traumatic injuries including fractures and head trauma from boom strikes, lacerations and impact injuries from high-pressure concrete discharge if hose fails, multiple casualties if truck or pump movements strike grouped workers, equipment damage and project delays from collision incidents, and prosecution liability for principal contractors and concreters if inadequate traffic management implemented.

Concrete placement creates extremely slippery surfaces due to wet concrete, concrete slurry on formwork, and cement residue on footwear and equipment. Finishing work requires workers to move across wet slab surfaces during screeding, bull floating, and final troweling. Formwork timber becomes slippery when wet, creating fall hazards during concrete placement when workers walk forms to guide concrete flow. Reinforcement mesh and bars protruding above slab surface create trip hazards particularly during early morning or evening pours in reduced lighting. Concrete slurry accumulates on site creating slippery conditions on access paths and around wash-down areas. Falls onto wet concrete or reinforcement steel create laceration and puncture injuries, while falls carrying tools or equipment create additional impact hazards.

Consequence: Lacerations and puncture wounds from falling onto reinforcement steel bars or mesh, fractures from falls onto concrete formwork or ground surfaces, serious injuries if workers fall while carrying vibrating equipment or heavy tools, infections from wounds contaminated with cement and soil, eye injuries if workers fall face-first into wet concrete getting cement in eyes, and drowning risk if workers fall unconscious into deep wet concrete.

Concrete placement and finishing occurs in outdoor environments often during summer months when ambient temperatures exceed 30-35 degrees Celsius. The exothermic reaction of concrete curing adds to ambient heat, with concrete surface temperatures reaching 40-50 degrees during hot weather. Concreters perform sustained heavy physical work during placement including pushing wheelbarrows loaded with 150-200kg of concrete, screeding operations using manual or vibrating screeds, and power troweling requiring constant movement and pressure application. Concrete setting times dictate work pace - workers cannot stop for extended breaks as concrete continues setting regardless of worker fatigue or heat stress symptoms. Placement work for typical residential slab requires 4-6 hours continuous physical exertion, with limited opportunity for rest or cooling. Protective equipment including long sleeves and waterproof gloves for cement protection increases heat retention reducing body cooling capacity.

Consequence: Heat exhaustion causing dizziness, nausea, excessive fatigue, and impaired decision-making increasing incident risk, heat stroke creating medical emergency with potential fatal outcome if not treated immediately, dehydration reducing physical capacity and increasing injury risk from manual handling, increased errors during finishing creating quality defects requiring expensive remediation, and collapse or loss of consciousness creating falling or struck-by hazards if worker becomes incapacitated while operating equipment or working near hazards.

Concrete finishing work requires sustained awkward postures creating accumulated musculoskeletal stress. Bull floating immediately after concrete placement requires workers to lean forward extending 3-4 metre float handles across slab surface while walking backward along slab edge. Power troweling requires operators to walk behind trowel machines applying downward pressure on handles while machine rotates beneath, creating sustained forward bending and arm loading for 3-5 hours. Hand troweling of edges and areas inaccessible to power trowels requires kneeling or squatting positions sustained for 30-60 minutes. Joint cutting using hand groovers requires kneeling while pulling groover through setting concrete along string lines, often for 200+ linear metres on commercial slabs. The setting time of concrete prevents workers from taking adequate breaks to recover from awkward postures - all finishing must complete before concrete becomes too hard to work, typically 2-4 hours after placement depending on weather conditions.

Consequence: Chronic lower back pain from sustained forward bending during power troweling and hand finishing, knee damage and osteoarthritis from prolonged kneeling on hard concrete surfaces, shoulder impingement and rotator cuff injuries from sustained overhead work and repetitive movement during finishing, neck strain from sustained head-down positions during detailed finishing work, accumulated musculoskeletal disorders requiring career change if work practices not improved, and acute injuries if workers lose balance from fatigue while in awkward positions near slab edges or operating equipment.