When a CO2 extinguisher is used in a confined space there is a danger that the user may become overwhelmed by the sudden increase in carbon dioxide emissions. This occurs as CO2 is an asphyxiant, and the confined space means oxygen will be replaced by CO2 much faster.
Similarly, care must also be taken when using powder extinguishers. When the powder is discharged it can impair visibility and impact the breathing of the user, possibly jeopardizing their escape. The possibility of the powder is inhaled or impairing visibility is dramatically increased when this type of extinguisher is used within a confined space.
