Halon 1211 extinguishers have a toxicity rating of what?

• A. 2
• B. 4
• C. 6
• D. 8

Answer: (C)

Toxicity rating reflects how harmful an extinguishing agent can be to people exposed to it. Higher numbers mean greater potential health risk from inhalation. Halon 1211 is rated 6, placing it in the mid-to-upper range for clean agents. This indicates that, while it is fast-acting and leaves no residue, exposure in enclosed spaces can cause adverse health effects such as dizziness or loss of consciousness and it can displace oxygen. Because of this, its use is planned with occupancy considerations in mind—evacuating people and ensuring adequate ventilation after discharge. The rating 6 is the established value for Halon 1211 in safety training materials.