On the manual handling of wide-body carts used by cabin attendants in civil aircraft.

A study was made of manual handling of wide-body carts used in civil aircraft. Under laboratory conditions, 11 females adjusted their pushing and pulling forces on fixed carts to the maximum amount they perceived as acceptable with repeated exertions. Subsequently their ability to push and pull the carts was tested with maximum exertions. The initial forces required to just get a fully loaded cart in motion were measured for different inclinations of the floor on which the cart stood. In a DC-9 aircraft, floor inclination and flying speed were measured while climbing to cruising altitude and during descent prior to landing. The maximum acceptable force for repetitive exertions was, on average, 68 N. The maximum force was, on average, 270 N. No significant differences were found between the pushing and pulling forces. The findings in the experiments caused the Swedish National Board of Occupational Safety and Health to reduce its recommended limit for repetitive push and pull in this task from 200 N to 100 N. As a result the handling of wide-body carts in the DC-9 should be delayed until at least 14-15 minutes after take-off to fulfil the new recommendation. On short flights, for which the DC-9 is used, this is not possible without reducing the level of service. A follow-up project on the development of an improved cart is under way, incorporating changes suggested in this paper and elsewhere.