What must firefighters use when entering an area after a clean agent discharge?

When entering an area after a clean agent discharge, firefighters must use a positive pressure breathing apparatus (SCBA). Clean agents, such as FM-200 or Novec 1230, are designed to suppress fires without causing harm to sensitive equipment or leaving residue. While they are effective in extinguishing flames, these agents can displace oxygen in the environment, which poses a risk of asphyxiation for anyone entering the area.

The use of SCBA provides firefighters with a secure supply of breathable air, ensuring that they can operate safely despite the potentially low oxygen levels or the presence of chemicals that may irritate the respiratory system. This safety equipment allows them to conduct necessary post-discharge activities, such as searching for remaining hot spots or ensuring the area is free of hazards.

Other options, while they have their own roles in firefighting operations, do not provide the critical respiratory protection needed in this specific scenario. Fire-resistant garments help protect against heat and flames, cooling gear is designed to manage body temperature during exposure to high heat, and radio communication devices are essential for coordination and safety but do not address the respiratory hazards present after a clean agent discharge. Thus, the necessity of using SCBA in such situations underscores its vital role in ensuring firefighter safety.