Hawaii Administrative Rules
Title 6 - DEPARTMENT OF BUDGET AND FINANCE
Division - PUBLIC UTILITIES COMMISSION
Chapter 77 - TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE; MINIMUM SAFETY STANDARDS
Subchapter 11 - MINIMUM SAFETY STANDARDS - REQUIREMENTS FOR CORROSION CONTROL
Section 6-77-135 - Internal corrosion control: monitoring

If corrosive gas is being transported, coupons or other suitable means must be used to determine the effectiveness of the steps taken to minimize internal corrosion. Each coupon or other means of monitoring internal corrosion must be checked two times each calendar year, but with intervals not exceeding seven and one-half months.