The Canadian Shield’s procedural masks are disposable and are intended for one-time use. Your face mask should be changed when it gets wet, visibility dirty, soiled or torn. Not only is it not possible to sterilize disposable masks, but the material of The Canadian Shield’s procedural masks are also electrostatically charged to filter micro-particles, and this charge is lost over time with wear. We recommend the use of a new disposable mask each day. For guidelines on how to safely remove and dispose of your procedural mask, click here.