What type of firewall is used to separate a rated floor from a non-rated curtain wall?

The correct choice is a firewall because it is specifically designed to prevent the spread of fire between different areas of a building, effectively containing any potential fire hazards. In the context of separating a rated floor from a non-rated curtain wall, a firewall acts as a crucial barrier that meets specific fire-resistance ratings. This ensures that the structural integrity of the building is maintained while providing a safe route for occupants in case of a fire.

Other types of walls, such as partition walls or load-bearing walls, do not provide the same level of fire protection. Partition walls primarily serve to divide spaces without the fire-resistance characteristics of a firewall. Load-bearing walls are structurally significant but are not primarily designed for fire resistance, and shear walls are intended to withstand lateral forces such as wind or seismic activity rather than to act as a fire barrier. Therefore, the unique purpose of a firewall in fire safety makes it the appropriate answer for this scenario.