A double sided square pvc plastic explaining the PPM of Carbon Monoxide / Lower Explosive Limit (LEL) / Oxygen / Hydrogen Sulfide levels and how their exposure can effect people.
 
Plus, they give examples of what can produce CO around the house. Newly added is the correct way to use positive and negative pressure to rid the scene of smoke and CO. Great for newer members and for explaining to the public where and what can cause CO around the house or workplace.