Provides limits for moisture content and for entrained particle size and oil content in instrument quality air. Establishes an awareness of sources of toxic or corrosive contamination coming into the system through the compressor suction, plant air system cross connection or instrument air connections connected to processes. Also identifies standard air supply pressures (with limit values) and operating ranges for pneumatic devices, gives the ranges of pneumatic transmission signals used in measurement and control systems between elements of systems. Includes, but is not restricted to, pneumatic controllers and control loops, pneumatic transmitters and information transmission systems, and current-to-pressure transducers. Also establishes criteria for testing compliance with instrument-quality air standards.