Abstract: The present invention provides an independent activation mechanism on both sides of a plastic sheath of a safety scalpel. Activation of either one of the mechanisms on the sides will cause the sheath to slide back along the handle neck and lock in place at the locking port thereby exposing the blade for use. The activation mechanisms are thumb activated on the side of the sheath, which results in a more natural motion as well as keeping other fingers out of the way of the unsheathed blade. After use, pushing forward with the thumb on either of the activation mechanisms on the sides of the plastic sheath will cause the sheath to slide forward and lock in place. Placement of the activation mechanisms on the sides of the sheath enable the top of the sheath to be flat and smooth which provides a comfortable surface for the practitioner.