7 Go beyond the traditional workspace - Mobile ergonomics with Treston carts Casters play an important role A quality caster is of the appropriate size in relation to the working environment and purpose of the cart. The bigger the caster, the easier it is to move the cart. For example, big casters make it easier to push the cart over thresholds and other similar obstacles. The tread in quality casters withstands wear and tear. The wheel/tread material is not the only factor influencing the usability and easy movability of the cart, as the flooring material also affects how well the caster rolls and moves. Swivel casters are also handy on a cart, making it easy to Consider the handle position and design Vertical handles are considered the most optimal, as every sized worker is able to grasp the handles in their unique power zone. Handles can be horizontal as well, as long as they are the correct height for the user. Preferred handle height is between the shoulder and knuckle height of the worker, optimizing the force applied for pushing and pulling. See image “Elbow height is the optimal position in regard to push forces” for reference. (6) Elbow height is the optimal position in regard to push forces. Displayed heights are indicative for average sized male. Shoulder height: 55” Elbow height: 40” Knuckle height: 32” Knee height: 24” Hip height: 37” The optimal shape for handles is cylindrical and smooth, which allows the best power grip with straight wrists. The handle diameter should be big enough to enable power grip instead of pinch grip. Power grip provides up to 75% more strength compared to pinch grip. Power grip involves grasping the handle by wrapping all the fingers around it, instead of grasping with thumb and tips of the other fingers. (6) maneuver even in small spaces. We recommend using four swivel casters in tight spaces, making it easier to turn and control loads. Strong caster brakes lock the cart in position, making sure that it stays where it is supposed to be. Casters have a big effect in minimizing the start forces needed to get the cart moving as well as in reducing the rolling resistance and therefore play an important role in ensuring proper ergonomics. The amount of force required to move loads with carts depends on a number of factors: • weight and shape of the load • type and condition of floor surface (e.g. smoothness and density) • route taken (e.g. slopes and obstacles) • type of caster, especially the materials used • size of caster • maintenance of casters – cleaning, lubricating and/ or replacing casters on a regular basis has a vital effect in maintaining the ride comfort and minimizing the push effort. (6)
RkJQdWJsaXNoZXIy NDk0Mw==