To operate a carbon dioxide extinguisher having the type of head shown in the illustration, you would __________. Illustration SF-0008

Correct Answer: Option B — pull pin and open valve

Operating a standard carbon dioxide extinguisher requires a two-step mechanical sequence: first, pull the safety pin to disengage the locking mechanism, and second, open the valve to release the pressurized gas. This design prevents accidental discharge while ensuring the extinguisher is ready for immediate use during a fire emergency.