Grand Scales General Code of Operating Rules – First Edition – January 1, 2007
A firebrick wall across the back end of the firebox immediately in front of and below the firebox door opening, toward which the fuel oil is delivered and which deflects the course of the flame.
Safety Valve A pressure sensitive valve located on the steam dome, which will release excess boiler pressure.
Spot Fire A light fire in the firebox.
Steam Gauge A pressure gauge located in the cab that indicates boiler pressure shown on a dial.
Water Glass A device for visually determining the water level in the boiler.