Final answer:
The preferred unit of measurement for pressure by respiratory therapists is millimeters of mercury (mm Hg) (option a), which is equivalent to a torr. One atmosphere (atm) is equal to 760 mm Hg or torr, and knowledge of conversions between different pressure units is important in medical settings.
Step-by-step explanation:
The preferred unit of measurement for pressure by many respiratory therapists is millimeters of mercury (mm Hg). This unit of pressure is also known as the torr, named after Evangelista Torricelli, who invented the barometer. It´s important to note that 1 atmosphere (atm) is defined as exactly 760 mm Hg, or 760 torr, which are equivalent measures. Pressure can also be measured in other units, such as centimeters of water (cm H2O), pounds per square inch (psi), and kilopascals (kPa), but these aren't typically used for respiratory therapy measurements.
It is crucial for respiratory therapists and others in medical fields to be able to convert between these different units of pressure, as different regions and devices might use different standards. The ability to interpret and convert measurements like 101.3 kPa, which equates to 760 mm Hg or torr, or 14.7 psi which is also equivalent to one atm, is central to ensuring accurate diagnosis and treatment.