Ergonomic Assessment of RTG Cranes
Port of Felixstowe
Background
The Port of Felixstowe is the largest container port in the UK and one of the largest in Europe. Rubber Tyred Gantry (RTG) cranes are large mobile cranes that are used for loading and unloading standard containers from road haulage vehicles and tugmaster tractor trailers. The containers are then retrieved and stacked within container park rows.
Project
To support the health and safety of their crane drivers, the Felixstowe Dock and Railway Company (FDRC) have undertaken a number of ergonomic studies. As part of this ongoing programme of work, we were commissioned conduct two programmes of research. The first involved a comparative ergonomics study of driving postural effort between different Rubber Tyred Gantry (RTG) cranes. The second programme entailed an ergonomics assessment of the effectiveness of enhancements / adaptations to a particular RTG model. The enhancements / adaptations included auto-steering, a remote viewing CCTV system and an anti-collision device.
Implementation
The research was conducted with a number of methods that included analysis of data (e.g. medical records, training records and technical specifications of the cranes); interviews with and observations of RTG crane drivers; and CAD analysis of driver posture, reach, vision and physical fit for each crane type using SAMMIE human modelling system (System Aiding Man Machine Interaction Evaluation).
Outcomes
It was found that the main source of ergonomics risk to the RTG drivers comes from the postures that they adopt when operating the RTGs. The most effective way of resolving these issues is the use of CCTV monitors within the cab. This would provide the required viewing capability for the drivers without them having to adopt awkward postures.
On this basis the following recommendations were made:
- CCTV monitors are installed in all RTG cabs to avoid the RTG drivers having to adopt poor postures when driving
- The CCTV monitors are installed correctly so that they show the required image, that there are no issues with monitor glare and the monitor does not obstruct the operator and/or impede their work
- The CCTV cameras need to be positioned on the RTG such that they show a good clear image with a suitable field of view under all lighting conditions to ensure that drivers can see on their monitors the various targets that they need to adequately and safely perform operations
- The design of the cab seating should be reviewed if CCTV based operation is to become the norm in RTGs. The postural improvements to be expected from this adaptation would only be achieved in conjunction with correctly designed and maintained seating.
- The anti-collision, CCTV and auto-steering should be implemented across all RTG cranes in the Port of Felixstowe. The auto steer and CCTV functions will be the most advantageous in terms of ergonomics risk, since they address postural problems, while the collision detection function is likely to offer operational and financial benefits.