On an open site the first control against being run over is not hi-vis. It is keeping people and moving plant apart.

The collision duty exists before the collision

An open worksite mixes the ingredients the WHS Regulations treat with the most suspicion: heavy powered mobile plant, vehicles arriving and leaving, and people on foot in the same ground. The primary duty is the familiar one, a person conducting a business or undertaking must ensure, so far as is reasonably practicable, that workers and others are not exposed to risk, which means eliminating the traffic risk where it can be eliminated and minimising it where it cannot. On top of that general duty the regulations add a specific one for machines that move. Where powered mobile plant is used, the person with management or control must manage the listed risks including the plant colliding with any person or thing, and the guide states the duty plainly: you must ensure the plant "does not collide with pedestrians or other powered mobile plant", and fit a warning device for the people at risk where a collision is possible. Officers carry a due-diligence duty to see that the business has these controls, and workers must take reasonable care and follow the reasonable instructions they are given. This page is about open-site traffic, the yard, the haul road, the laydown area, the loading zone in the open. For the indoor version, forklifts, docks and the high risk work licence, see the warehouse and forklift page; for the wider plant duties of guarding, maintenance and registration, see the plant and machinery page.

Separation first: the hierarchy on an open site

The guide walks the ordinary hierarchy of controls in traffic terms, and the order matters because the law requires the highest practicable control first. Elimination comes before everything: in a loading zone you can design out the reversing vehicle with a drive-through layout, multi-directional plant or a rotating cab, and on a road job you can close the road rather than run traffic through the work. Substitution is next, a safer machine or method in place of the risky one, electronic traffic control or lights instead of a person directing traffic, mechanical means instead of workers on foot. Then comes the control that does the heavy lifting on an open site, isolation, physically separating people from plant so the two cannot meet. The guide's catalogue is concrete: overhead or fenced walkways, barriers and guardrails at the points where someone could step out in front of a machine, separate entry and exit points for people and for large vehicles, and exclusion zones, plant-only areas around an operating excavator or a loading bay, pedestrian-only areas around crib rooms, amenities and site entrances. Where a hard barrier is not practicable, delineation devices define the path: cones, bollards, barrier boards and containment fencing that keep a walking route clear of the traffic route. Engineering controls sit below isolation, speed limiters on the plant, proximity detection and collision-avoidance systems that warn when a machine is closing on a person or another machine, and lighting placed to remove the glare and shadow that hides a person from an operator. Only then do the administrative controls arrive, and the high-visibility vest arrives last of all. Hi-vis is genuine PPE with genuine duties attached, but as the PPE page explains, the law puts it at the bottom of the order, and a traffic plan that leads with it has the hierarchy upside down: a barrier does not get tired, and a walkway that never crosses a haul road needs no one's vigilance to work.

Reversing is where it goes wrong

The single most repeated open-site failure is a machine or a vehicle moving where no one meant it to, and reversing is the sharp end of it. The guide's first answer is again to eliminate the reverse, with drive-through layouts, so that a vehicle never has to back toward people. Where a reverse cannot be removed, the administrative controls are specific: a competent person to direct the reversing vehicle where the driver cannot see clearly behind, in visible contact with the driver at all times and wearing high-visibility clothing, and designated reversing areas that are clearly marked, signposted and well lit. Speed management supplements those controls rather than replacing them, and signs and road markings warn operators and pedestrians of the blind corners, crossings and exclusion zones the layout depends on. None of this is theoretical. This masthead's running read of the NSW mining incident summaries has found the same category of event in the detailed incidents week after week: a drill rig boom striking a light vehicle at an underground intersection, a dozer and a haul truck reversing toward each other on a dark, dusty ramp, a haul truck reversing into a dozer, a reversing van with no working alarm or camera striking a worker. The NSW Resources Regulator's advice in those cases lands on exactly the controls above: positive, confirmed communication between machines before anyone moves, proximity and collision-avoidance technology, and lighting laid out so every operator can see what is around them. The hazard is not unique to a mine. It is a reversing truck in a yard, a loader working next to a walkway, and a vehicle backing at a loading dock.

The traffic management plan is the document that proves it

For a workplace with a high volume of traffic, or work on or near a public road, the guide does not leave traffic control to habit; it expects a written traffic management plan, developed by a competent person, tested on site by both the people who wrote it and the people who must follow it, and kept available to workers. The guide lists what the plan should contain: the duties and responsibilities of the people involved, the risks and the controls to be implemented, the desired flow of pedestrian and vehicle movement including the space plant operators need to get in and out of their machines safely, the expected frequency of interaction between vehicles and pedestrians, illustrations of the layout of barriers, walkways and signs, and how short-term, mobile and complex situations will be handled. For roadwork the plan also defines the familiar zones, the advance warning area, the taper that guides traffic past the work, the safety buffer that absorbs a driver's error before it reaches a worker, the work area itself and the termination area where normal conditions resume. Like every control, the plan is meant to be a living one: the guide requires it to be monitored and reviewed regularly, and specifically after an incident, so that a near miss on Tuesday changes the layout by Wednesday rather than waiting for the version that never gets updated. A plan that sits in a folder and never changes after a close call is not doing the job the guide describes.

What the enforcement and the pattern say

Regulators treat this as a front-line hazard, not a paperwork one. In a statewide compliance operation reported in March 2025, SafeWork NSW inspectors issued more than 140 notices in a single push on mobile plant, fixed machinery and vehicles across the agricultural, retail, construction, manufacturing and transport sectors, with most of the notices relating to forklift and separation risks, and on-the-spot fines available of up to $4,500 for a business and $900 for an individual. The head of SafeWork NSW, Trent Curtin, framed being hit by moving plant or vehicles, and injuries around fixed machinery, as preventable hazards the regulator sees across the state. The weekly resources-sector picture points the same way: for five consecutive editions the NSW Resources Regulator's detailed incidents have featured vehicle interaction or unplanned plant movement, which is why its advice keeps returning to separation, communication, proximity technology and lighting. The through-line for a duty-holder in any industry is the one the guide states at the top. The most reliable control is the one that does not depend on a person paying attention at the wrong moment: keep people and moving plant apart, and where they must share ground, engineer and plan the interaction rather than trusting a vest and a glance over the shoulder.