Cert III Agricultural Mech key terms

The legal obligation of employers, workers and others to take reasonable steps to protect anyone affected by workplace activities from injury or harm, including following procedures and reporting hazards.

Any situation, substance, machine or activity with the potential to cause injury, illness or damage to property or the environment, whether or not it has yet caused harm.

The likelihood that a hazard will actually cause harm, combined with how severe that harm would be, usually assessed before deciding what controls are needed.

A structured process of identifying hazards, judging how likely and how serious the resulting harm could be, and deciding which controls are appropriate before work starts.

A ranked order of risk treatments, from eliminating the hazard through substitution, engineering controls and administrative controls, down to personal protective equipment as the least reliable option.

Clothing and equipment worn by a worker, such as boots, gloves, hearing protection, eye protection or a respirator, to reduce exposure to hazards that cannot be removed another way.

A written document that sets out the steps of high-risk work, the hazards involved, the controls to be used and how the controls will be monitored and reviewed.

A task-based planning tool that breaks a job into steps, identifies the hazards in each step and records the controls and responsibilities before the work begins.

A written or electronic record used to notify supervisors of an unsafe condition, near miss or faulty equipment so that the issue can be assessed, controlled and tracked to closure.

Any activity that requires a person to lift, lower, push, pull, carry or otherwise move a load by bodily force, including awkward postures and repetitive movements.

A procedure in which an energy source is isolated, locked in the off position and tagged with the worker's name so machinery cannot be started during maintenance or repair.

The documented steps for shutting down a machine, disconnecting or bleeding off all stored energy, proving the machine is de-energised and securing it before work proceeds.

A clearly marked control that immediately halts machine movement or power when pressed, used when a person or property is at risk and reset only after the cause is cleared.

A rating that shows which types of fire an extinguisher suits, such as wood and paper, flammable liquids, flammable gases, or electrical equipment, so the correct unit is chosen.

The responsibility to prevent pollution and minimise harm to soil, water, air and vegetation during agricultural work, including safe handling and disposal of fuels, oils and chemicals.

A supplier document that describes a chemical's hazards, safe handling, storage, first aid, spill response and required protective equipment, kept accessible wherever the chemical is used.

The practice of keeping agricultural chemicals in a secure, ventilated, bunded area away from food, stock, water sources and ignition sources, with labels intact and records kept.

The sequence of intake, compression, power and exhaust strokes that a piston completes in four movements of the piston, with the crankshaft turning twice per cycle.

An engine cycle that produces a power stroke every crankshaft revolution, using ports and crankcase pressure to draw in and transfer the fuel-air mixture, usually requiring oil mixed with fuel.

The ratio of the cylinder volume above the piston at bottom dead centre to the volume remaining at top dead centre, which affects power, efficiency and fuel octane requirements.

The small measured gap between the rocker or cam follower and the valve stem, set to the manufacturer's specification so valves open and close fully as the engine warms.

The system that delivers a measured quantity of diesel into the combustion chamber at the correct moment and pressure, using a pump, injectors and timing that must be set precisely.

A device that mixes fuel with air in the correct proportion for a spark-ignition engine, using a venturi, jets and a throttle plate, and often adjustable for idle and high-speed mixture.

A component that removes dirt, rust and water from fuel before it reaches the pump and injectors, protecting precision parts and preventing loss of power or hard starting.

A serviceable element that traps dust and chaff before it enters the engine, protecting cylinders and rings from abrasive wear; it is cleaned or replaced at set intervals.

A lubricant graded by viscosity and service class that reduces friction, carries heat away and holds contaminants in suspension; its level and condition are checked regularly.

The radiator, pump, thermostat, hoses and coolant that keep an engine at its designed operating temperature, preventing overheating and maintaining efficient combustion.

A pressure-relief cap that raises the boiling point of coolant and releases pressure safely; it must never be removed from a hot engine because of scalding risk.

A closed circuit of pump, valves, hoses and cylinders that transmits force through pressurised oil to lift, steer or operate implements on tractors and machinery.

A pressure-storing device in some hydraulic circuits that holds oil or gas under pressure even after the engine stops, so stored energy must be released before servicing.

A flexible reinforced line that carries pressurised oil between components; it must be inspected for cracking, chafing and leaks, and pinhole leaks must never be searched for by hand.

The standard mounting system of two lower links and one top link that connects an implement to a tractor and controls its lift, depth and angle.

A splined shaft on a tractor that drives powered implements at a standard speed, protected by guards and never approached while rotating.

The resistance of a tractor to tipping or rolling, affected by track width, centre of gravity, implement load, speed, slope and tyre pressure, and improved by ballasting and safe driving.

A frame or cab built to protect the operator if a tractor overturns; it only works when the seat belt is worn and it must not be modified or drilled.

A calibrated tool that applies a set twisting force to a fastener so bolts, especially cylinder heads and wheel nuts, are tightened to the manufacturer's specification without damage.

A component that supports a rotating shaft and reduces friction, commonly a sealed ball or roller type that is pressed into a housing and needs correct alignment and lubrication.

A small fitting through which grease is forced into a bearing or pivot with a grease gun during scheduled lubrication, flushing out dirt and water.

A heavy towing point at the rear of a tractor or vehicle used to pull trailed implements, rated for a maximum load and fitted with a safety pin or hitch.