Kerbside Waste Collection Round Risk Assessment by Means of Physiological Parameters: sEMG and Heart Rate

The occupational health risks in waste collection workers have been widely investigated. Many studies show that workers are exposed to several risk factors. Aim of the study is biomechanical risk assessment of kerbside waste collection workers. The paper focused on the task that literature showed as the most overloading, that is emptying the bin in the lorry. Simulations were made in a rubbish dump where upper limbs and trunk muscles activity were recorded through surface electromyography (sEMG) to verify the biomechanical load for the four emptying techniques usually adopted. It was also recorded heart rate of workers during the collection round to determine their Relative Cardiac Cost (RCC). sEMG results for the task of emptying the bin, showed a significant effort of the paravertebral muscles for each techniques. About upper limbs, sEMG showed that emptying the bin directly into the collection lorry from the back was the most overloading technique. This is due to the workers arms raise well over shoulder height. The lightest technique was the emptying of the bin inside a certified container but, due to its small volume, this led to an increase in collection round time. RCC results showed moderate activity, according to the Chamoux scale, in three of the four workers, only one of them showed a quite heavy activity. A redesign of the collection lorries with certified and larger containers would reduce the risk. It would be also desirable a turnover of employees to allow them to work alternatively in areas of high population density, with higher risk, and in low-density areas with lower risk.