Electric static charges generated from friction of engineering materials have a negative effect on their applications. The increased use of polymeric materials raised the importance of studying that effect. Electric static charges building up on human skin and or clothes in direct contact with human body are very harmful and can create serious health problems. The present study investigates the electric static charge generated from the dry and water wet sliding of shoe cover against floor for people who are working in hospitals. It was found that, at dry testing condition, friction coefficient displayed by sliding of polyethylene shoe cover against epoxy floor increased with increasing normal load. It is necessary that friction coefficient should have reasonable values so that the foot slip should be avoided to prevent accidents, where the values satisfied the European standards for safe use at dry sliding condition. Electric static charge, of relatively higher values, generated on the shoe cover from contact and separation against dry floor was similar to that generated by sliding. As the load increased the charge decreased. This observation can confirm the necessity to develop new materials to be applied as shoe cover of low electric static charge. At water wet testing condition, friction coefficient displayed relatively lower values. Voltage generated on the shoe cover from its contact and separation as well sliding against water wet epoxy floor showed lower values than that observed for dry condition due to the ability of water to conduct the charge from the contact surfaces.
Ali et al. (Thu,) studied this question.