In connection with the procurement of trolley buses it ought to be considered if cushion seats without suspension, conventional suspension seats or suspension seats according to the specifications of the joint project "Driver´s workplace in the standard transport bus" of the Institution for Statutory Accident Insurance and Prevention in the railway-, metropolitan railway and tramway sector are suitable.
On the initiative of the Institution for Statutory Accident Insurance and Prevention in the railway-, metropolitan railway and tramway sector the driver´s vibration exposure was measured on a suspension seat with blocked suspension and on a suspension seat in working order in two trolley buses of the same type on the same route. To clarify if the nature of the vibration in new trolley buses and low floor buses are comparable despite the different chassis or essentially differing, three low floor buses of the same type were included in the test. Additionally driver´s seats were included in the measurement series which fulfil the requirements as defined in the joint project of the Institution for Statutory Accident Insurance and Prevention of the railway-, metropolitan railway and tramway sector. In all vehicles the vibration exposure was measured at the seat mounting point (chassis) and on the seat in three directions of vibration: back-breast, shoulder-shoulder and spinal column of the seated driver.
Trolley buses and low floor buses are as far as the character of the vibrations are concerned comparable. The greatest vibration reduction is in every case achieved by a suspension seat that meets the requirements of the specifications of the joint project "Driver´s workplace in the standard transport bus". A softer adjustment of the damper is as far as the vibrations are concerned more favourable than a harder adjustment of the damper although it is preferred by the drivers because of the "better contact with the vehicle". Older suspension seats with a higher resonance frequency and a harder damper are barely superior to rigid cushion seats without suspension for the reduction of vibration. Anyhow occasionally occurring single thrusts are distinctly better suspended through the suspension seats; therefore suspension seats are to be preferred before cushion seats without suspension.
trafficType of hazard:
Arbeitsbedingte Erkrankungen, Arbeitsbedingte Gesundheitsgefahren, Lärm/VibrationenCatchwords:
Vibration, Schutzmaßnahme, GefährdungsbeurteilungDescription, key words:
Trolley bus, low floor bus, driver´s workplace, driver´s seat, whole-body vibrations, seat selection