Supporting existing safe passing protocols and procedures the scalpel has a reinforced temporary lock in the forward user position ensuring the blade will stay extended even if it encounters a hard surface or bone during use. When in the retracted position the slider mechanism contains a notch that holds the blade securely in the retracted position. A permanent lock position at the rear of the scalpel, requiring a conscious amount of force to engage the slider, ensures the contaminated blade remains retracted whilst disposing in an appropriate sharps container at the end of the procedure.