The visibility audit: a conceptual framework for the assessment of visibility around trucks and industrial vehicles

The Visibility Audit is proposed as a framework to further structure research and development in the field of visibility offered by vehicles to their users. This conceptual tool is being designed to help quantify visibility around vehicles in order to reduce occupational accidents. Like the financial audit, it subtracts any structural, accessory or environmental impediments to vision (liabilities) from openings in the cab and supplemental visibility offered by some devices (assets). As a demonstration, a Visibility Audit was carried out on the mock-up of a straight-body truck. The openings and structures of the cab were measured and transferred to a computer-assisted drawing software. The projection of a light source, located at the driver's cyclopean eye location, on a hexahedral screen is simulated by computer. Visibility is expressed as the surface area totalling all the lighted areas on all sides of the screen. The audit calculated a loss of 44% in visibility following the installation of a 22 foot long cargo box to the rear of the cab. Installing large (600 square cm) flat mirrors on the cab subtract 29 square m from the available visibility on the sides, but allows a supplemental 113 square m of reflected visibility from the rear. The Visibility Audit can be a simple and powerful tool to assess visibility around trucks and other heavy vehicles providing it is integrated in an ergonomic approach. (A) For the covering abstract, see IRRD 892069.