83 Ill. Adm. Code 501.210
Orifice Meters
Section 501.210 Orifice Meters
a) A
utility shall install all new orifice meters in accordance with the
recommendation of AGA Report No. 3, Orifice Metering of Natural Gas and Other
Related Hydrocarbon Fluids, Part 2, Specification and Installation Requirements,
XQ0002 (April 2000 and June 2003).
b) A
utility furnishing metered gas service through orifice meters shall provide and
have available instruments capable of accurately determining the accuracy of
the orifice plate diameters and instruments used to measure meter pressure and
temperature to within 0.5%.
c) At
least every six months, a utility shall inspect an orifice meter's orifice
plate and meter body and inspect and verify the proper operation of all
transmitters used to measure pressures and temperatures.
d) If a
utility discovers that the orifice plate is deformed, damaged or bowed, the
utility shall replace the plate within seven days. If the utility finds that
the orifice plate is deformed, damaged or bowed on two consecutive inspections,
the utility shall document the problem and conduct inspections at least every
three months on the orifice plate until three consecutive inspections show no
damage. If the utility cannot obtain three consecutive inspections showing no
damage after 24 months, the utility shall take corrective action, such as
installing a strainer upstream of the meter, to avoid continued damage to the
orifice plate.
e) A utility shall maintain
five years of inspection records.