The following checklist provides a general practice information:
Carbon Monoxide (CO) alarms are not substitutes for smoke alarms. Smoke alarms react to fire by-products, before CO alarms would sound. Smoke alarms give earlier warning of a fire, providing more time to escape.
To guard against smoke and fire, be sure that your home has working smoke alarms on every level and in or near all sleeping areas.
Know the difference between the sound of the smoke alarms and the sound of the CO alarms.
Have a home escape plan for any home emergency and practice the plan with all members of the household regularly, at least twice a year.