A method of sanitizing articles in a wash chamber of a washing machine appliance is provided. The method includes providing the wash chamber with an oxygen bleach wash additive and, optionally, with a detergent wash additive, determining a water fill volume target, and adding a first wash volume of water to the wash chamber. The first wash volume is determined based on a fixed percentage of the water fill volume target in is less than the water fill volume target such that the oxygen bleach wash additive is present in a relatively concentrated amount.
