[Working tasks with upper limbs repetitive movements: analysis of different methods for risk assessment]

A review of different methods for the risk assessment of upper limbs repetitive movements is carried out mainly referring to a recent ISO standard (ISO 11228-3). This standard establishes ergonomic recommendations for tasks involving manual handling of low loads at high frequency (repetitive work). It is a "voluntary" standard and provides information for all professionals involved in occupational prevention as well as in job and product design. It refers to a four-step approach, involving both risk assessment and risk reduction (hazard identification, risk estimation, risk evaluation and risk reduction). General reference is made to a general model reported in a Consensus Document published by the IEA Technical Committee "Musculoskeletal Disorders", with the endorsement of ICOH. Apart from risk identification, the standard addresses and suggests several methods for a simple risk estimation (i.e. Plibel, Osha Checklist, Upper Limb Expert Tool, Qec, Checklist Ocra). If the risk estimation results in the 'yellow' or 'red' zone, or if the job is composed by two or more repetitive tasks, a more detailed risk assessment is recommended. For a detailed risk assessment, the OCRA method is suggested as "preferred"; however, other methods (STRAIN INDEX; HAL-TLV-ACGIH) can also be used. The applicative limits of the methods mentioned above, considering the purposes of the standard, are shortly discussed together with their recent scientific updates and applicative perspectives. The standard, with the suggested risk assessment procedures and methods, represents a useful tool for all OSH operators involved in the application of European and National legislation regarding the prevention of UL WMSDs.