How much time from Halon discharge should the fire team wait before attempting re-entry?

How much time from Halon discharge should the fire team wait before attempting re-entry?

• A. 5 minutes
• B. 10 minutes
• C. 15 minutes
• D. 20 minutes

Answer: (C)

After Halon discharge, the space must be purged and the atmosphere allowed to recover before anyone re-enters. Halon rapidly floods and displaces air and can leave toxic byproducts; giving about 15 minutes for ventilation to reduce agent concentration and for oxygen levels to rebound minimizes the risk of asphyxiation and inhalation of toxic gases. Re-entry should only occur once atmospheric monitors show the space is safe—typically oxygen around 19.5% or higher with Halon/toxic byproducts at safe levels. If the monitors still read unsafe conditions, continue purging and ventilating until they’re within safe limits.

After Halon discharge, the space must be purged and the atmosphere allowed to recover before anyone re-enters. Halon rapidly floods and displaces air and can leave toxic byproducts; giving about 15 minutes for ventilation to reduce agent concentration and for oxygen levels to rebound minimizes the risk of asphyxiation and inhalation of toxic gases. Re-entry should only occur once atmospheric monitors show the space is safe—typically oxygen around 19.5% or higher with Halon/toxic byproducts at safe levels. If the monitors still read unsafe conditions, continue purging and ventilating until they’re within safe limits.