The recommended handle diameters for circular-handle tools such as screwdrivers are 3 to 5 cm when a power grip is required, and 0.75 to 1.5 cm when a precision finger grip is needed. Avoid sharp edges and pinch points. Select tools that will not cut or pinch the hands even when gloves are not worn. Avoid repetitive trigger-finger actions. Select tools with large switches that can be operated with all four fingers.
Proximity switches are the most desirable triggering mechanism.
Isolate hands from heat, cold, and vibration. Heat and cold can cause loss of manual dexterity and increased grip strength requirements. Excessive vibration can cause reduced blood circulation in the hands causing a painful condition known as white-finger syndrome. Wear gloves that fit. Gloves reduce both strength and dexterity.