An exposure on the left side of the fire building may be designated as exposure:

In fire service operations, exposures are identified using a standardized system to help firefighters communicate effectively about the layout of a structure and its surroundings. The exposure designations refer to the sides of a building in relation to the front where the main entrance is located.

The left side of the fire building is designated as exposure B or 2. This designation assists firefighting personnel in quickly identifying the location of potential hazards or secondary structures that might be affected by the fire. Each side of the building is assigned a specific letter and number for uniformity, where "A" or "1" corresponds to the front, "B" or "2" to the left side, "C" or "3" to the rear, and "D" or "4" to the right side.

Thus, recognizing that exposure B or 2 specifically pertains to the left side of the fire building is crucial for effective communication during emergency response situations.