Official Journal of the Italian Society of Orthopaedics and Traumatology
Table 1 Descriptions of work classification [6]
From: Factors influencing return to work after hip and knee arthroplasty
Sedentary work | Exerting up to 10 lb of force occasionally (occasionally: activity or condition exists up to 1/3 of the time) and/or a negligible amount of force frequently (frequently: activity or condition exists from 1/3 to 2/3 of the time) to lift, carry, push, pull, or otherwise move objects, including the human body. Sedentary work involves sitting most of the time, but may involve walking or standing for brief periods of time. Jobs are sedentary if walking and standing are required only occasionally and all other sedentary criteria are met |
Light work | Exerting up to 20 lb of force occasionally, and/or up to 10 lb of force frequently, and/or a negligible amount of force constantly (constantly: activity or condition exists 2/3 or more of the time) to move objects. Physical demand requirements are in excess of those for sedentary work. Even though the weight lifted may be only a negligible amount, a job should be rated light work: (1) when it requires walking or standing to a significant degree; or (2) when it requires sitting most of the time but entails pushing and/or pulling of arm or leg controls; and/or (3) when the job requires working at a production rate pace entailing the constant pushing and/or pulling of materials even though the weight of those materials is negligible. The constant stress and strain of maintaining a production rate pace, especially in an industrial setting, can be and is physically demanding of a worker even though the amount of force exerted is negligible |
Medium work | Exerting 20 to 50 lb of force occasionally, and/or 10 to 25 lb of force frequently, and/or greater than negligible up to 10 lb of force constantly to move objects. Physical Demand requirements are in excess of those for light work |
Heavy work | Exerting 50 to 100 lb of force occasionally, and/or 25 to 50 lb of force frequently, and/or 10 to 20 lb of force constantly to move objects. Physical demand requirements are in excess of those for medium work |
Very heavy work | Exerting in excess of 100 lb of force occasionally, and/or in excess of 50 lb of force frequently, and/or in excess of 20 lb of force constantly to move objects. Physical demand requirements are in excess of those for heavy work |