Machine Guarding Compliance Under WHS Regulation 2025

Machine guarding is the primary engineering control that prevents worker contact with dangerous parts of machinery including rotating shafts, gears, belts, cutting tools, press dies, and conveyor nip points. The WHS Regulation 2025 requires that every machine with dangerous parts is fitted with guards or safety devices that prevent access to the danger zone during operation. Machine guarding failures remain the leading cause of serious injury prosecutions in Australian manufacturing, with regulators consistently finding guards removed, interlocks bypassed, and safety devices defeated. After Section 26A commences on 1 July 2026, the Managing Risks of Plant in the Workplace Code of Practice becomes legally binding. This code sets detailed requirements for guard design, interlock specifications, safe distance calculations, and maintenance that become enforceable as standalone obligations. Manufacturers that rely on informal guarding arrangements or have not reviewed their machine guarding against the code requirements should conduct a comprehensive audit before the July 2026 commencement date.

The code of practice recognises several guard types, each suited to different machine configurations and operational requirements. Fixed guards are permanently attached to the machine frame and can only be removed with tools. They are the most reliable guard type because they cannot be easily defeated, and they should be used wherever access to the danger zone is not required during normal operation. Interlocked guards are movable guards connected to an interlock switch that stops the machine when the guard is opened. They are used where frequent access is needed for loading, unloading, or adjustment, but the machine must be stopped before access. Guard locking interlocked guards add a locking mechanism that prevents the guard from being opened until the machine has reached a safe state, such as the spindle stopping completely. These are used on machines where the danger continues after power is removed due to inertia. Adjustable guards allow the guard opening to be adjusted to suit different workpiece sizes while maintaining protection. Tunnel guards restrict access to the danger zone by limiting the approach path to a narrow channel that prevents hands reaching the danger point. The selection of guard type must be based on a risk assessment of the specific machine and the tasks performed on it.

Australian Standard AS 4024 specifies the safety distances that must be maintained between guard openings and danger zones based on the size of the opening and the part of the body that could pass through it. These calculations ensure that even if a worker can reach through a guard opening, their hand or fingers cannot reach the danger zone. For example, a slot opening of 12 mm or less prevents finger access and allows the danger zone to be positioned at any distance behind the guard. A slot opening of 20 mm allows finger insertion up to the second knuckle and requires the danger zone to be at least 120 mm behind the guard. An opening of 120 mm or more allows full arm insertion and requires the danger zone to be at least 850 mm from the opening. These calculations must be applied to every guard opening on every machine, including gaps between guard panels, openings for material feed, and access points for operator controls. Manufacturers should measure all guard openings against the AS 4024 tables during their guarding audit and retrofit any openings that allow reach-through access to danger zones.

Interlocked guards are only as reliable as their interlock systems. An interlock that can be easily defeated — by inserting a screwdriver, cable tie, or piece of wire to hold the switch in the closed position — provides no protection. The code of practice requires interlocks to be designed so that they cannot be easily defeated using readily available items. Coded interlocks that use unique key, tongue, or magnetic coding are significantly more defeat-resistant than simple position switches. RFID-coded interlocks offer the highest level of defeat resistance. The performance level of the interlock system must be matched to the risk level of the machine using the risk assessment methodology in AS 4024. High-risk machines such as presses and robot cells require Performance Level d or e interlocks with redundancy, diagnostics, and self-monitoring. Interlock systems must be functionally tested at defined intervals to verify that they stop the machine when the guard is opened. Testing should be documented with the date, tester, machine identification, and pass/fail result. Any interlock that fails functional testing must be repaired before the machine returns to service.

A machine guarding compliance program should begin with a comprehensive audit of every machine on the factory floor, assessing the current guarding against the requirements of the Managing Risks of Plant Code of Practice and AS 4024. The audit should document the guard type, interlock configuration, safe distance compliance, interlock defeat resistance, and overall condition of each guard on each machine. Any non-conformances should be classified by risk level and addressed in priority order. The program should include a machine guarding register that lists every machine, its guards, interlock types, and inspection schedule. Scheduled inspections at defined intervals verify that guards remain in place, interlocks function correctly, and no defeats have been introduced. A guard removal permit system requires formal authorisation before any guard is removed for maintenance and verification that the guard is replaced before the machine returns to service. All interlock bypasses must be reported as critical safety incidents, investigated, and corrected. Worker training should cover the purpose of guards, the prohibition against defeat, and the reporting obligation when guards are damaged or missing. EHS Atlas manages the complete guarding compliance program including the machine register, inspection scheduling, corrective actions, and training records.