Louisiana Administrative Code
Title 55 - PUBLIC SAFETY
Part V - Fire Protection
Chapter 50 - Boiler Construction, Maintenance, Inspection and General Use
Subchapter C - Existing Installations- Power Boilers
Section V-5045 - Water Gage Glasses

A. Each steam boiler shall have one or more water gage glasses attached to the water column or boiler by means of valved fittings not less than 2 inch pipe size, with the lower fitting provided with a drain valve of a type having an unrestricted drain opening not less than 1/4 inch in diameter to facilitate cleaning. Gage glass replacement shall be possible under pressure. Water glass fittings may be attached directly to a boiler.

B. Boilers having an internal vertical height of less than 10 inches may be equipped with a water level indicator of the glass bulls-eye type provided the indicator is of sufficient size to show the water at both normal operating and low water cutoff levels.

C. The lowest visible part of the water gage glass shall be at least 1 inch above the lowest permissible water level recommended by the boiler manufacturer. With the boiler operating at this lowest permissible water level, there shall be no danger of overheating any part of the boiler.

D. Each boiler shall be provided at the time of manufacture with a permanent marker indicating the lowest permissible water level. The marker shall be stamped, etched, or cast in metal; or it shall be a metallic plate attached by rivets, screws, or welding; or it shall consist of material with documented tests showing its suitability as permanent marking for the application. This marker shall be visible at all times. Where the boiler is shipped with a jacket, this marker may be located on the jacket.

E. In electric boilers of the submerged electrode type, the water gage glass shall be so located to indicate the water levels both at startup and under maximum steam load conditions as established by the manufacturer.

F. In electric boilers of the resistance heating element type the lowest visible part of the water gage glass shall not be below the top of the electric resistance heating element. Each boiler of this type shall also be equipped with an automatic low-water electrical power cutoff so located as to automatically cut off the power supply before the surface of the water falls below the top of the electrical resistance heating elements.

G. Tubular water glasses on electric boilers having a normal water content not exceeding 100 gallons shall be equipped with a protective shield.