The scope of this Standard is

a) to provide limits for moisture content in instrument quality air;

b) to provide limits for entrained particle size and oil content in instrument quality air;

c) to establish an awareness of possible sources of corrosive or toxic contamination entering the air system through the compressor suction, plant air system cross connection, or instrument air connections directly connected to processes;

d) to establish standard air supply pressures (with limit values) and operating ranges for pneumatic devices;

e) to specify ranges of pneumatic transmission signals used in measurement and control systems between elements of systems. It includes, but is not limited to, the following:

1) Pneumatic controllers

2) Pneumatic transmitters and information transmission systems

3) Current-to-Pressure transducers

4) Pneumatic control loops; and

f) to establish criteria for testing compliance with instrument-quality air standards.

Purpose

The purpose of this Standard is to establish a standard for instrument quality air.