In B28 installations, what defines a control area?

• A. A secured room where only management can access.
• B. A corridor adjacent to the system.
• C. A zone around the system with controlled ventilation and restricted ignition sources to minimize ignition risk.
• D. A general workspace with no ventilation requirements.

Answer: (C)

In B28 installations, the control area is the zone around the system where ventilation is actively managed and ignition sources are restricted to minimize ignition risk. This matters because flammable refrigerant vapors can accumulate and ignite if there isn’t enough ventilation or if ignition sources are present. By defining a control area, you ensure that ventilation is provided to dilute any leaked vapor and that activities or equipment that could ignite vapors—like open flames, welding, or unclassified electrical equipment—are controlled or prohibited within that boundary. This safety boundary is what keeps potential leaks from reaching flammable concentrations and helps firefighters and operators work within a clearly protected space. The other options don’t address these essential safeguards for vapor management and ignition prevention.