Workplaces often require areas greater than the AS 1428 access standard series and we’re often asked about ramps within workplaces and Designers WHS 2012 duty of care which is reason for this guide note.
The dimensions in AS 1428.1 were initially based on studies by J. Bails, Project report on the field testing of the Australian Standard 1428-1977 Part 1 and 2, Public Building Department of South Australia, 1983. It’s important to remember that Bails research analysed the anthropometry of wheeled mobility users which is similar but different to workplace needs.
While there’s detailed guide documents for the design of health facilities generally, the requirements for safe people handling is limited and often refers to AS 1428.1 standard for access. The risk factors that we consider in designing ramps in workplaces is the magnitude of the forces that have to be exerted. Reducing the risk means decreasing the forces to the lowest level as practicable. Key factors impacting on push and pull forces include floor gradients and materials, and high forces when manoeuvring wheeled equipment increased the risk of musculoskeletal disorders.
Our best state of knowledge on pushing and pulling on ramps in workplaces is based on the work of Snook and Ciriello. (1991) The design of manual handling tasks: revised table of maximum acceptable weights and forces. Ergonomics 34.9:1197-1213, P37 gradients and slopes
“The forces required to manually push wheeled equipment up a slope will increase as the gradient of the slope increases. The total force is equal to that required to push the equipment on a horizontal surface, plus a force component due to the slope. It is preferable to avoid slopes where wheeled equipment is manually moved . If this is not practicable, control measures to reduce the force …..(Administrative controls are lower order controls that rely on human behaviour and may be used only in conjunction with, or where implementation of higher order controls such as engineering controls ….are not reasonably practicable).” End quote.
For guidance Aged Care, we often refer to ‘A guide to designing workplaces for safer handling of people’ from work-safe Victoria and if you’re working with the guide you may have found it tends to conflict with the BCA requirements for access. This is why we get called in at the early stages to rule out any uncertainties about WHS and access ramps in workplaces that often plague projects.