Which factor does NOT affect the effectiveness of a Type B extinguisher?

The factor that does not affect the effectiveness of a Type B extinguisher is the time of day. The effectiveness of fire extinguishers is influenced by their design, how they are stored, their physical condition, and the specific type of fire they are meant to combat.

The storage environment is critical because an extinguisher must be kept in a location where it is easily accessible and protected from extreme temperatures. The type of fire extinguished is vital since Type B extinguishers are specifically designed to handle flammable liquids and gases, meaning their effectiveness is directly linked to the fire type they are intended for. Similarly, the physical condition of the extinguisher matters, as a device that is damaged or not properly maintained may not function correctly in an emergency.

Time of day has no bearing on the operational capabilities of the extinguisher itself. Regardless of whether it is day or night, a properly maintained Type B extinguisher should perform its function effectively when needed, assuming other relevant conditions are met.