The pressure reducer block reduces cylinder pressure to what range under normal conditions?

The correct range for the pressure reducer block is 85-110 psi under normal conditions. This range is significant because it ensures a consistent and safe supply of gas for use in respiratory equipment, such as self-contained breathing apparatus (SCBA).

When the pressure reducer is functioning properly, it adjusts the high cylinder pressure to a lower, manageable level that is suitable for the various requirements of firefighting and emergency response operations. The target pressure range is calibrated to meet industry standards and to protect both the user and the equipment from potential over-pressurization, ensuring that the breathing apparatus operates effectively under pressure conditions that allow for both safety and performance.

The other ranges listed do not align with the operational standards for pressure reducers in fire service equipment, either being too low or too high, which could lead to inadequate performance or safety hazards.