Final answer:
The correct instrument air quality requirement is that it must be dry to a dew point of -30 Fahrenheit to prevent moisture from damaging instruments or affecting measurements.
Step-by-step explanation:
Regarding the instrument air quality requirements, the correct option is B) shall be dry to a dew point of -30 Fahrenheit. This specification relates to ensuring the air used in instruments does not contain moisture that could condense, which potentially damages delicate instrumentation or affects accurate readings. The dew point is the temperature at which air is saturated with moisture and will begin to condense. Keeping the dew point very low, such as -30 Fahrenheit, ensures that even as temperatures fluctuate, the risk of condensation within the instrument air supply remains minimized.
Furthermore, option A) is related but refers to specific compliance standards set by the American National Standards Institute and the International Society of Automation, while option D) refers to standards for medical air, which are particular to healthcare settings and not general instrumentation.
Lastly, option C) appears to be a typo or incomplete, but it seems to relate to filtration levels (though the common unit for filtration would be microns or μm). Proper filtration is indeed important for preventing particulates from harming instrumentation or affecting measurements.