Facilities who have very strict standards and/or have a patient population that tends to have severe infection issues usually purchase two harnesses from Mobility Research so they can have one in use while one is in the wash. For less severe cross contamination issues, consider using blue pads/chux between the harness pieces and the patient to prevent soiling.
The harness can be washed in the washing machine with cold water and regular detergent but must be air dried (no heat). The washing frequency is determined by the facility and/or department.