Conveyor System Safety Engineering Design Lyttelton Port Company

The Client

Lyttelton Port Company (LPC) is a major New Zealand port operator managing bulk material import and export operations. The site runs a large and complex conveyor network that includes export lines, import conveyors, reclaimers, stackers and ship loaders, all within a high-risk, heavy industrial environment.

The Goal

LPC’s existing local guarding was insufficient to adequately safeguard the conveyor hazards and was not practical for maintenance. The size and weight of the guards meant they were often not properly reinstated after removal. LPC set out to develop a compliant safeguarding and control design for its conveyor system using the AS/NZS 4024.3610, 3611 and 3614 conveyor standards.

The design needed to address access to hazards including nip and shear points, exposed rotating parts, falling or projected material, and energy hazards during operation and maintenance. It applied a Zone A and Zone B safeguarding methodology specifically at the head and tail end pulleys, convex curves (brow positions), snub and take-up pulleys of the bulk material handling (BMH) conveyors, and the travelling tripper, along with emergency stops, pull wires, interlocked access, and isolation and restart controls across the conveyor lines.

The objective was to give LPC site-specific design outputs for upgrading conveyor safety across an operating port environment and to standardise future conveyor safety upgrades.

Why TEG Risk

TEG Risk was engaged to undertake Summary Machine Risk Assessments (SMRAs) of the conveying system following a fatal incident in which a person was engulfed in coal dust. The assessments identified multiple deficiencies in the existing local guarding: guarding that was not fit for purpose, with hooks used to hang fixed panels, and openings that allowed reach-through and reach-over access to hazards. TEG Risk issued a clear, practical report that included a prioritised action register and recommendations aligned with AS/NZS 4024.3610, 3611 and 3614.

Engaging the design team called for proven expertise in conveyor safety, including bulk materials handling systems, mobile plant, and interfacing equipment across complex operational environments. LPC required assurance that site-specific conditions were fully considered, with safeguarding and control upgrades developed to be practical and effective across project, operations and maintenance perspectives. The work involved detailed interpretation and application of AS/NZS 4024.3610, AS/NZS 4024.3611, AS/NZS 4024.3614 and AS/NZS 4024.1801 across a range of fixed, mobile and transportable conveyor systems.

The Solution

TEG Risk established the applicable standards hierarchy, drawing on AS/NZS 4024.3610 for general conveyor requirements, AS/NZS 4024.3611 for bulk materials handling conveyors, AS/NZS 4024.3614 for mobile and transportable conveyors, and AS/NZS 4024.1801 for guard opening and reach distances.

A Zone A and Zone B safeguarding methodology was used. Zone A hazards were safeguarded, while Zone B was assessed on risk, operating conditions, access frequency, pre-start warnings and personnel exposure.

Perimeter fencing was specified as the primary safeguarding method for accessible hazard areas, with a 1 m reach to pulley hazards, a 1.8 m minimum guard height, 120 mm maximum gaps through or around guards, an 850 mm minimum reach distance to hazards, and a 180 mm maximum clearance beneath guards. Interlocked access gates and trapped key systems were applied to guarded areas, typically allocating one trapped key per area or conveyor, with key switches and exchanges located at the relevant MCC or safety control panel. Solenoid release considerations were included where stopping time or process conditions influenced safe access to hazards after a stop command was initiated.

Emergency stop and pull wire design was standardised, with readily accessible emergency stop devices at operator stations, pull wire coverage along accessible conveyor lengths, compliant pull wire support spacing, and fail-safe activation on wire break, slackening or removal. Hold-to-run requirements were defined for movement functions on luffing and slew conveyors.

TEG Risk produced equipment-specific retrofit solutions, including local fixed guarding, guard extensions, relocation of controls outside fenced areas, walkovers and crossovers, handrails, toe kicks, counterweight protection, cable reel guards, track wheel guards, bucket wheel guards and fall prevention measures.

Challenges

The LPC system included a broad mix of export and import conveyors, transfer areas and large mobile plant, which meant the same design principles had to be adapted to very different layouts and access conditions. Many areas had constrained space, with existing platforms, pits, cable routes and walkway arrangements that affected where perimeter fencing, interlocked gates and local guarding could be fitted. Several hazard zones required the safe stopping of multiple conveyors or interfacing plant when a single access gate was opened, such as where adjacent conveyor ends shared access. The design also had to balance safeguarding with maintainability, so that inspection, lubrication, cleaning and routine tasks could still be carried out effectively and safely.

Results

TEG Risk delivered a site-specific conveyor safety engineering design that set out compliant safeguarding, access and control solutions across the LPC conveyor systems. The work standardised the safety architecture for LPC, including Zone A perimeter fencing, interlocked access, trapped key systems, emergency stops, pull wires, reset methodology, isolation and hold-to-run functions where required.

It defined clear retrofit actions for high-risk exposure points such as tail ends, head ends, counterweights, cable reels, track wheels, bucket wheel couplings, shafts, accessible snub rollers, and climb-over or reach-around points. The design improved the basis for safe maintenance by incorporating walkway clearance, crossover access, handrails, toe kicks, control relocation and guarding arrangements that reduce the need to remove guards for routine tasks. The result gave LPC a practical upgrade roadmap aligned to current conveyor safety standards and suited to staged implementation in an operating port environment.

The Engineers

The LPC conveyor safety engineering design was developed by TEG Risk’s machine safety engineers, Andrey Zhidkov and Charles Webb.

Andrey Zhidkov  

Safety and Electrical Engineer, TEG Risk

Andrey is a Chartered Professional and degree-qualified Electrical Engineer. He is a Certified Functional Safety Application Expert (CFSAE), accredited through SGS TÜV Saar, and a Certified Machinery Safety Expert (CMSE), accredited through TÜV Nord. His experience spans the design of material handling systems, process engineering, industrial controls and consultancy, with a focus on project-based management and risk improvement across operations and engineering environments.

Charles Webb

Machine Safety Engineer, TEG Risk

Charles is an experienced Machine Safety Engineer with a demonstrated history in industrial machinery design and construction. He is skilled in machine risk assessment and functional safety, machine and control systems design and build, electronics and PCB design, and mechanical product design and build. He holds a Bachelor of Engineering Technology focused on mechatronics, robotics and automation engineering.

Client Feedback

“We engaged Andrey and Charles from TEG Risk to develop a guarding solution for our existing conveyor system to ensure it met current guarding specifications and safety requirements in New Zealand.

From the outset, both were highly professional, flexible, and easy to work with throughout the entire process. They took the time to understand our operational requirements and design brief and ultimately presented a solution that fully met our expectations.

The final product was delivered to an exceptionally high standard and exceeded expectations in both quality and execution. Their collaborative approach and willingness to adapt throughout the project made the process straightforward and efficient.

We would have no hesitation in recommending Andrey, Charles, and TEG Risk to others seeking a professional and capable team able to deliver high-quality safety and engineering solutions.”