PART II - Dept. of Transportation - Coast Guard - June 21,1990
46CFR Part 39 Vapor Control Systems
Subpart 39.20 Design and Equipment
§ 39.20-3 Cargo gauging system -TB/ALL

39.20-3 Cargo gauging system-TB/ALL

(a) Each cargo tank of a tank vessel that is connected to a vapor collection system must be equipped with a cargo gauging device which:

(1) Provides a closed gauging arrangement as defined in Sec. 151.15.10 of this chapter that does not require opening the tank to the atmosphere during cargo transfer;

“The Full Model View SGM-1 Marine Sight Glass satisfies this requirement. ”

(2) Allows the operator to determine the liquid level in the tank for the full range of liquid levels in the tank;

“The Radial Arm Gauge Tree satisfies this requirement.”

(3) Indicates the liquid level in the tank at the location where cargo transfer is controlled; and

(4) If portable, is installed on the tank during the entire transfer operation. (b) Except when a tank barge complies with Sec. 39.20-9(a) of this part each cargo tank of a barge must have a high level indicating device that:

“The DS-39 Rising Stick Gauge satisfies this requirement.”

(1) Provides a visual indication of the liquid level in the cargo tank when the cargo level is within 1.0 meter (3.28 feet) of the tank top;

(2) Has the maximum liquid level permitted under 39.30-1(e) of this part at even keel conditions conspicuously and permanently marked on the indicating device; and

(3) Is visible from all cargo control areas on the tank barge.